GB2623826A

GB2623826A - Method and system for controlling a vehicle for travelling on a curved road

Info

Publication number: GB2623826A
Application number: GB2216047.7A
Authority: GB
Inventors: Yoshida Tadashi; Hasegawa Toru
Original assignee: Continental Autonomous Mobility Germany GmbH
Current assignee: Continental Autonomous Mobility Germany GmbH
Priority date: 2022-10-31
Filing date: 2022-10-31
Publication date: 2024-05-01
Also published as: GB202216047D0; DE102023210507A1

Abstract

Method of controlling a vehicle travelling on a curved road, including: detecting a curvature of the curved road based on a local perception sensor system of the vehicle; calculating a vehicle target speed for travelling on the bend based on the detected curvature of the curved road; and determining whether to adjust the target vehicle speed based on a sensed lateral acceleration of the vehicle. The target speed may be reduced if the detected lateral acceleration is above a threshold. Decision whether to adjust target speed is performed iteratively until the radius of the curvature is below a threshold. Sensor data may be lane marking, road sign, or speed limit sign. The target speed may be a cruse control speed. Method may be performed only when satellite navigation or online road map is not available. Sensors may include camera, sonar, radar, lidar.

Description

METHOD AND SYSTEM FOR CONTROLLING A VEHICLE FOR TRAVELLING ON A CURVED ROAD

TECHNICAL FIELD

The present invention generally relates to a method of controlling a vehicle for travelling on a curved road, and a system thereof, and more particularly, in relation to cruise control.

BACKGROUND

Various cruise control technologies are known in the art and a cruise control system is becoming a common feature in modern vehicles (e.g., cars, trucks, busses and so on). In general, a cruise control system installed in a vehicle automatically controls the speed of the vehicle according to a cruise control speed set by the driver. For example, the cruise control may automatically disengage or deactivate when the driver depresses the brake. Over time, there have been improvements or advancements in cruise control technologies, such as adaptive cruise control (ACC). For example, while cruising, adaptive cruise control further automatically adjusts the speed of the vehicle to maintain a safe distance to a preceding vehicle (e.g., the vehicle directly or immediately ahead). As a result, while cruising, it is not necessary for the driver to manually brake and accelerate repeatedly to maintain a safe distance to a preceding vehicle (which may also undesirably disengage cruise control), thereby enhancing driver experience of cruise control.

However, conventional cruise control systems, including advanced cruise control systems such as adaptive cruise control systems, may suffer from problems in navigating curved roads, especially those having a tight (or sharp) curve. For example, such conventional cruise control systems may be prone to being disengaged when approaching to, or travelling on, a curved road as the driver may depress the brake because the vehicle travelling at a speed according to the cruise control speed set by the driver may be too fast for the curved road, thus causing discomfort or safety concerns. There have also been disclosed cruise control systems that attempt to control the speed of the vehicle for a curved road. However, such cruise control systems attempt to control the speed of the vehicle for travelling on a curved road based on a global navigation satellite system (GNSS) signal (e.g., GPS or GLONASS signal) and a road map database (e.g., at a remote server), which may not always be available (e.g., no or insufficient wireless signal coverage (e.g., GNSS coverage and/or cellular network coverage), such as in a tunnel or along a road surrounded by tall buildings, which may also be referred to as a GNSS denied environment), and thus may render such cruise control systems ineffective or lo inoperable for curved roads when a GNSS signal and/or a road map database is unavailable. For example, it is difficult to ensure that a GNSS signal and a road map database (e.g., at a remote server) are always available. Accordingly, such cruise control systems may be prone to reliability issues in navigating a curved road, thereby degrading driver experience of cruise control.

A need therefore exists to provide a method and a system for controlling a vehicle for travelling on a curved road that seek to overcome, or at least ameliorate, one or more problems associated with conventional methods and systems for cruise control, and in particular, enhancing or improving reliability or effectiveness of cruise control, thereby enhancing driver experience of cruise control. It is against this background that the present invention has been developed.

SUMMARY

According to a first aspect of the present invention, there is provided a method (e.g., a computer-implemented method) of controlling a vehicle for travelling on a curved road using at least one processor, the method comprising: determining a curvature of the curved road based on first sensor data obtained by a local perception sensor system of the vehicle with respect to a surrounding environment; determining a target vehicle speed for travelling on the curved road based on the curvature of the curved road determined; and determining whether to adjust the target vehicle speed based on a lateral acceleration of the vehicle detected.

In various embodiments, the above-mentioned determining whether to adjust the target vehicle speed comprises: determining whether the lateral acceleration of the vehicle detected is higher than a lateral acceleration threshold; and decreasing the target vehicle speed based on determining that the lateral acceleration of the vehicle detected is higher than the lateral acceleration threshold.

In various embodiments, the above-mentioned determining the curvature of the curved road, the above-mentioned determining the target vehicle speed and the above-mentioned determining whether to adjust the target vehicle speed are performed in an iterative loop until a curvature of a road ahead of the vehicle is determined to be less than a curvature threshold.

In various embodiments, the iterative loop further comprises outputting final target vehicle speed information after the above-mentioned determining whether to adjust the target vehicle speed.

In various embodiments, the first sensor data comprises lane marking information.

In various embodiments, the method further comprises: detecting the curved road at a distance ahead of the vehicle based on second sensor data obtained by the local perception sensor system of the vehicle with respect to the surrounding environment; and determining whether to adjust a set cruise control vehicle speed based on the second sensor data.

In various embodiments, the second sensor data comprises road sign information.

In various embodiments, the road sign information comprises speed limit information for the curved road, and the above-mentioned determining whether to adjust the set cruise control vehicle speed comprises: determining whether the set cruise control vehicle speed is higher than a speed limit indicated by the speed limit information; and decreasing the set cruise control vehicle speed based on determining that the set cruise control vehicle speed is higher than the speed limit indicated by the speed limit information.

lo In various embodiments, the road sign information further comprises road curve sign information for the curved road, and the curved road at the distance ahead of the vehicle is detected based on the road curve sign information In various embodiments, the method further comprises: detecting a start of the curved road based on third sensor data obtained by the local perception sensor system of the vehicle with respect to the surrounding environment; and determining whether to adjust or further adjust the set cruise control vehicle speed for entering the curved road based on the third sensor data.

In various embodiments, the third sensor data comprises lane marking information.

In various embodiments, the method further comprises determining availability of a wireless navigation signal and/or a road map database, and the above-mentioned determining the curvature of the curved road, the above-mentioned determining the target vehicle speed and the above-mentioned determining whether to adjust the target vehicle speed are performed for the curved road based on determining that the wireless navigation signal and/or the road map database is unavailable.

In various embodiments, the method further comprises controlling a speed of the vehicle according to the final target vehicle speed information and/or displaying the final target vehicle speed information on a driver information interface.

In various embodiments, the local perception sensor system comprises one or more of a camera-based perception sensor system, a radar-based perception sensor system, a sonar-based perception sensor and a lidar (light detection and ranging)-based perception sensor system.

In various embodiments, the vehicle is operating under cruise control.

According to a second aspect of the present invention, there is provided a system for ro controlling a vehicle for travelling on a curved road, the system comprising: at least one memory; and at least one processor communicatively coupled to the at least one memory and configured to perform the method according to the above-mentioned first aspect of the present invention.

According to a third aspect of the present invention, there is provided a vehicle comprising: the system according to the above-mentioned second aspect of the present invention; and the local perception sensor system communicatively coupled to the system and configured to obtain sensor data with respect to a surrounding environment.

According to a fourth aspect of the present invention, there is provided a computer program product, embodied in one or more non-transitory computer-readable storage mediums, comprising instructions executable by at least one processor to perform the method according to the above-mentioned first aspect of the present invention.

BRIEF DESCRIPTION OF THE DRAWINGS

Embodiments of the present invention will be better understood and readily apparent to one of ordinary skill in the art from the following written description, by way of example only, and in conjunction with the drawings, in which FIG. 1 depicts a schematic flow diagram of a method of controlling a vehicle for travelling on a curved road, according to various embodiments of the present invention; FIG. 2 depicts a schematic block diagram of a system for controlling a vehicle for travelling on a curved road, according to various embodiments of the present invention; FIG. 3 depicts a schematic block diagram of an example system for controlling a vehicle for travelling on a curved road, according to various example embodiments of the present invention; FIG. 4 depicts a schematic flow diagram of an example method of controlling a vehicle for travelling on a curved road, according to various example embodiments of the present invention; and FIG. 5 depicts an illustrative scenario of a vehicle approaching a curved road and travelling along the curved road, according to various example embodiments of the present invention.

DETAILED DESCRIPTION

Various embodiments of the present invention provide a method of controlling a vehicle for travelling on a curved road, and a system thereof, and more particularly, in relation to cruise control. It will be understood by a person skilled in the art that that various embodiments described below may be combined, for example, a pad of one embodiment may be combined with a part of another embodiment. That is, various embodiments are not necessarily mutually exclusive, as some embodiments can be combined with one or more other embodiments to form new embodiments and are within the scope of the present invention.

As described in the background, various cruise control technologies and systems are known in the art, and thus need not be described herein in detail for clarity and conciseness. However, as explained in the background, conventional cruise control systems, including advanced cruise control systems such as adaptive cruise control ro systems, may suffer from problems in navigating curved roads, especially those having a tight (or sharp) curve. For example, such conventional cruise control systems may be prone to being disengaged when approaching to, or travelling on, a curved road, or may be ineffective or inoperable for a curved road when a wireless navigation signal (e.g., a GNSS signal) and/or a road map database (e.g., at a remote server) is unavailable (e.g., in a GNSS denied environment), thereby degrading driver experience of cruise control. A need therefore exists to provide a method and a system for controlling a vehicle for travelling (or driving) on (or along) a curved road that seek to overcome, or at least ameliorate, one or more problems associated with conventional methods and systems for cruise control, and in particular, enhancing or improving reliability or effectiveness of cruise control, thereby enhancing driver experience of cruise control.

FIG. 1 depicts a schematic flow diagram of a method 100 of controlling a vehicle for travelling on a curved road using at least one processor, according to various embodiments of the present invention. The method 100 comprising: determining (at 102) a curvature of the curved road based on first sensor data obtained by a local perception sensor system of the vehicle with respect to a surrounding environment; determining (at 104) a target vehicle speed for travelling on the curved road based on the curvature of the curved road determined; and determining (at 106) whether to adjust the target vehicle speed based on a lateral acceleration of the vehicle detected.

B

In various embodiments, the above-mentioned determining (at 102) the curvature of the curved road, the above-mentioned determining (at 104) the target vehicle speed and the above-mentioned determining (at 106) whether to adjust the target vehicle speed may be performed while the vehicle is travelling (or cruising) on (or along) the curved road under cruise control. Accordingly, the method 100 of controlling a vehicle for travelling on a curved road has advantageously been found to enhance or improve reliability or effectiveness of cruise control, and more particularly, for curved roads, thereby enhancing driver experience of cruise control. Firstly, the target vehicle speed determined based on the curvature of the curved road may be lo adjusted (e.g., reduced) based on a lateral acceleration of the vehicle detected, thereby improving the comfort level and/or safety of the driver (and any passenger(s)) in the vehicle. For example, excessive lateral acceleration of the vehicle may thus be avoided, or at least mitigated, thereby avoiding or minimising the need for the driver to depress the brake (which may in turn disengage cruise control) to reduce the lateral acceleration due to discomfort and/or safety concerns.

Furthermore, the curvature of the curved road is determined based on sensor data obtained by a local perception sensor system of (or onboard) the vehicle (which may also be referred to herein as local sensor data) with respect to a surrounding environment (e.g., based on lane marking information obtained (or captured) by a camera system). As a result, the method 100 of controlling the vehicle for travelling on a curved road is able to continue to operate under cruise control effectively with vehicle speed management regardless of the availability of a wireless navigation signal (e.g., a GNSS signal) and/or a road map database (e.g., at a remote server) (e.g., vehicle in a GNSS denied environment), thereby advantageously enhancing or improving reliability or effectiveness of cruise control, which in turn enhances driver experience of cruise control. These advantages or technical effects, and/or other advantages or technical effects, will become more apparent to a person skilled in the art as the method 100 of controlling a vehicle for travelling on a curved road, as well as the corresponding system for controlling a vehicle for travelling on a curved road, is described in more detail herein according to various embodiments and example embodiments of the present invention.

In various embodiments, the above-mentioned determining (at 106) whether to adjust the target vehicle speed comprises: determining whether the lateral acceleration of the vehicle detected is higher than a lateral acceleration threshold; and decreasing the target vehicle speed based on determining that the lateral acceleration of the vehicle detected is higher than the lateral acceleration threshold.

It will be understood by a person skilled in the art that the lateral acceleration threshold may be set as appropriate based on various factors, such as driver and/or passenger comfort level, safety level and/or applicable regulations. For example, the lateral acceleration threshold may also be set according to driver preference (e.g., lo sport mode vs comfort mode) as long as it complies with safety and/or applicable regulations. For example, the lateral acceleration of the vehicle may be detected based on one or more motion sensors installed in (or onboard) the vehicle, such as an inertial measurement unit (IMU), a gyroscope and/or an accelerometer. Accordingly, the method 100 may further comprise obtaining lateral acceleration information, indicating the lateral acceleration of the vehicle detected, from the one or more sensors. For example, when the vehicle is travelling along a curved road, the lateral acceleration of the vehicle may be defined as the acceleration of the vehicle transverse or perpendicular to the direction of travel of the vehicle, which may also be referred to as the centripetal or centrifugal force. In various embodiments, if the lateral acceleration of the vehicle is determined to be higher than the lateral acceleration threshold, the amount of target vehicle speed to be reduced may be determined based on the amount by which the lateral acceleration exceeds the lateral acceleration threshold, such as but not limited to, a proportional amount. It will be appreciated by a person skilled in the art that the present invention is not limited to any particular or specific manner in which the target vehicle speed is decreased, as long as the target vehicle speed is decreased if the lateral acceleration of the vehicle detected is higher than the lateral acceleration threshold. Accordingly, the comfort level and/or safety of the driver (and any passenger(s)) in the vehicle can be improved, as well as enhancing effectiveness and driver experience of cruise control.

In various embodiments, the above-mentioned determining (at 102) the curvature of the curved road, the above-mentioned determining (at 104) the target vehicle speed and the above-mentioned determining (at 106) whether to adjust the target vehicle speed are performed in an iterative loop until a curvature of a road ahead (e.g., immediately ahead) of the vehicle is determined to be less than a curvature threshold. In other words, until the road is determined to no longer be a curved road. In various embodiments, the iterative loop further comprises outputting final target vehicle speed information (indicating a final target vehicle speed determined) after the above-mentioned determining (at 106) whether to adjust the target vehicle 1.0 speed. Accordingly, the iterative loop may be continuously performed while the vehicle is travelling (or cruising) along the curved road under cruise control, thereby determining the target vehicle speed and determining whether to adjust the target vehicle speed at each corresponding iteration along the curved road, so as to determine a final target vehicle speed (e.g., corresponding to the target vehicle speed determined at 104 if no adjustment at 106 or the adjusted target vehicle speed if adjusted at 106) at each iteration. Accordingly, in various embodiments, at each iteration, the above-mentioned determining (at 102) the curvature of the curved road, the above-mentioned determining (at 104) the target vehicle speed and the above-mentioned determining (at 106) whether to adjust the target vehicle speed are performed with respect to a corresponding section or part of the curved road (e.g., a corresponding section of the curved road directly or immediately ahead of the vehicle that is captured (or sensed) by the local perception system of the vehicle (e.g., a camera system configured to at least capture or sense a surrounding environment ahead of the vehicle)). Accordingly, the target vehicle speed may be continuously determined and adjusted (if deemed necessary) while the vehicle is travelling (or cruising) along the curved road under cruise control, thereby advantageously providing a smooth and effective cruise control along the curved road, and enhancing driver experience of cruise control.

In various embodiments, the curvature threshold may be set as appropriate such as based on a minimum degree of curvature (e.g., defined by radius of curvature) for the road to be considered (or determined) as a curved road (or for the corresponding section of the road to be part of the curved road). Accordingly, it will be understood by a person skilled in the art that the curvature threshold is not limited to any particular or specific value, but may be set as appropriate or preferred, such as for defining a minimum degree of curvature for the road to be considered as a curved road, and thus for controlling the vehicle according to the method 100 for such a curved road determined. By way of examples only and without limitation, a minimum degree of curvature may have a radius of curvature of 200 m or less, optionally 150 m or less, optionally 100 m or less or optionally 50 m or less. In various example embodiments, the minimum degree of curvature may be configured for a tight (or lo sharp) curve, such as having a radius of curvature of 50 m or less, optionally 40 m or less or optionally 30 m or less.

Accordingly, the curvature of the curved road may be determined based on lane marking information in the first sensor data obtained (or captured) by the local perception sensor system of the vehicle with respect to the surrounding environment. In various embodiments, the local perception sensor system may comprise a camera-based perception sensor system (which may simply be referred to as a camera system) configured to capture or sense visual information (i.e., images or videos) at least with respect to the surrounding environment ahead of the vehicle, such as of at least the road ahead of the vehicle (e.g., a section of the road directly or immediately ahead of the vehicle), such that the visual information captured include lane marking information of the road ahead of the vehicle. Accordingly, in various embodiments, the curvature of a road (or a section thereof) may be defined by, or determined with respect to, lane markers (or lane markings) along the road.

Accordingly, by determining the curvature of the curved road based on sensor data obtained by the local perception sensor system of the vehicle with respect to a surrounding environment, and more particularly, based on lane marking information captured in the sensor data of the road ahead the vehicle, the method 100 of controlling the vehicle for travelling on a curved road is able to continue to operate under cruise control effectively with vehicle speed management regardless of the availability of a wireless navigation signal (e.g., GNSS signal) and/or a road map database (e.g., at a remote server) (e.g., even if the vehicle is in a GNSS denied environment), thereby advantageously enhancing or improving reliability or effectiveness of cruise control, which in turn enhances driver experience of cruise control.

In various embodiments, the method 100 further comprises: detecting the curved road at a distance ahead of the vehicle based on second sensor data obtained by the local perception sensor system of the vehicle with respect to the surrounding environment; and determining whether to adjust a set cruise control vehicle speed io based on the second sensor data. For example, the set cruise control vehicle speed may be set by a driver of the vehicle or dynamically set based on adaptive cruise control with respect to a preceding vehicle, or may be automatically set in the case of an autonomous vehicle or autonomous driving. Accordingly, the above-mentioned detecting the curved road at a distance ahead of the vehicle may be performed at a distance from a start of the curved road to be detected. For example, the distance may be based on the location of one or more road curve signs alerting drivers of the curved road at a distance ahead. For example, the one or more road curve signs may be road signage(s) on a side of the road and/or road marking(s) on the road. Accordingly, by detecting the curved road at a distance ahead of the vehicle based on sensor data obtained by the local perception sensor system of the vehicle with respect to a surrounding environment, the method 100 is able to detect the curved road at a distance ahead of the vehicle regardless of the availability of a wireless navigation signal (e.g., GNSS signal) and/or a road map database (e.g., at a remote server), thereby advantageously enhancing or improving reliability or effectiveness of cruise control.

In various embodiments, the second sensor data comprises road sign information.

Accordingly, the curved road at a distance ahead of the vehicle may be detected based on road sign information in the second sensor data obtained (or captured) by the local perception sensor system of the vehicle with respect to the surrounding environment. In various embodiments, similarly as described above, the local perception sensor system may comprise the above-mentioned camera system configured to capture or sense visual information (i.e., images or videos) at least with respect to the surrounding environment ahead of the vehicle, such as at least the road (and sides thereof) ahead of the vehicle, such that the visual information captured include road sign information such as road signage(s) on a side of the road and/or road marking(s) on the road alerting drivers of the curved road at a distance ahead.

In various embodiments, the road sign information comprises speed limit information for the curved road, and the above-mentioned determining whether to adjust the set lo cruise control vehicle speed comprises: determining whether the set cruise control vehicle speed is higher than a speed limit indicated by the speed limit information; and decreasing the set cruise control vehicle speed based on determining that the set cruise control vehicle speed is higher than the speed limit indicated by the speed limit information. In this regard, the set cruise control vehicle speed may be decreased to the speed limit indicated by the speed limit information. Accordingly, by obtaining sensor data, including speed limit information, using the local perception sensor system of the vehicle, the method 100 is able to decrease the set cruise control vehicle speed if necessary to comply with the speed limit for the curved road regardless of the availability of a wireless navigation signal (e.g., a GNSS signal) and/or a road map database (e.g., including road attribute information, such as speed limit information, road type information and so on, at a remote server), thereby advantageously enhancing or improving reliability or effectiveness of cruise control.

In various embodiments, the road sign information further comprises road curve sign information for the curved road, and the curved road at the above-mentioned distance ahead of the vehicle is detected based on the road curve sign information. As described above, the road curve sign information may correspond to one or more road curve signs alerting drivers of the curved road ahead, such as road signage(s) on a side of the road and/or road marking(s) on the road.

In various embodiments, the method 100 further comprises: detecting a start of the curved road based on third sensor data obtained by the local perception sensor system of the vehicle with respect to the surrounding environment; and determining whether to adjust or further adjust the set cruise control vehicle speed for entering the curved road based on the third sensor data. In various embodiments, similar to the above-mentioned first sensor data, the third sensor data may comprise lane marking information. Accordingly, the start of the curved road may be determined based on lane marking information in the third sensor data obtained (or captured) by the local perception sensor system of the vehicle with respect to the surrounding environment, and more particularly, at least with respect to the surrounding environment ahead of the vehicle, such as of at least the road ahead of the vehicle lo (e.g., a section of the road directly or immediately ahead of the vehicle), such that the visual information captured include lane marking information of the road ahead of the vehicle. In various embodiments, the start of the curved road may be determined based on the commencement of the curvature of the curved road as determined based on the lane marking information in the third sensor data obtained. Accordingly, by determining the start of the curved road based on sensor data obtained by the local perception sensor system of the vehicle with respect to the surrounding environment, and more particularly, based on lane marking information captured in the sensor data of the road ahead the vehicle, the method 100 of controlling the vehicle for travelling on a curved road is able to continue to operate under cruise control effectively with vehicle speed management regardless of the availability of a wireless navigation signal (e.g., a GNSS signal) and/or a road map database (e.g., at a remote server), thereby advantageously enhancing or improving reliability or effectiveness of cruise control, which in turn enhances driver experience of cruise control.

In various embodiments, the above-mentioned determining whether to adjust or further adjust the set cruise control vehicle speed for entering the curved road based on the third sensor data comprises determining a curvature of the curved road (e.g., in the same or similar manner as the above-mentioned determining a curvature of the curved road at 102); and determining a target vehicle speed for travelling on the curved road based on the curvature of the curved road determined (e.g., in the same or similar manner as the above-mentioned determining a target vehicle at 104). The set cruise control vehicle speed may then be adjusted (or further adjusted if it was already adjusted as described hereinbefore when the vehicle was at the above-mentioned distance ahead of the curved road) based on the target vehicle speed determined. For example, the set cruise control vehicle speed may be decreased to the target vehicle speed determined if the set cruise control vehicle speed is higher than the target vehicle speed determined.

In various embodiments, the method 100 further comprises determining availability of a wireless navigation signal and/or a road map database, and the above- to mentioned determining (at 102) the curvature of the curved road, the above-mentioned determining (at 104) the target vehicle speed and the above-mentioned determining (at 106) whether to adjust the target vehicle speed are performed (or the above-mentioned detecting the curved road at a distance ahead of the vehicle or the above-mentioned detecting a start of the curved road is performed) for the curved road based on determining that the wireless navigation signal and/or the road map database is unavailable. In various embodiments, the availability of the wireless navigation signal may be determined to be unavailable if there is no or insufficient wireless navigation signal coverage or strength at the vehicle (e.g., at a GNSSdenied environment). For example, wireless navigation signal may be any wireless signal that can be received by a receiver installed in a vehicle to determine the location of the vehicle, such as a GNSS signal (e.g., GPS or GLONASS signal). In various embodiments, the availability (or accessibility) of the road map database may be determined to be unavailable (or inaccessible) if there is no or insufficient wireless network coverage (e.g., mobile or cellular network coverage) for retrieving (or accessing) information from the road map database (e.g., located at a remote server), such as road configuration information and road attribute information (e.g., speed limit information, road type information and so on). Accordingly, in various embodiments, multiple cruise control mode for a curved road may be provided, such as first cruise control mode configured to operate (or primarily operate) based on a wireless navigation signal and a road map database, and a second cruise control mode configured to operate (or primarily operate) based on local sensor data obtained from the local perception sensor system onboard the vehicle. In this regard, the first cruise control mode may be selected for controlling the vehicle for travelling on a curved road if the wireless navigation signal and the road map data based are determined to be available. On the other hand, the second cruise control mode may be selected for controlling the vehicle for travelling on a curved road if the wireless navigation signal and/or the road map data based is determined to be unavailable.

Accordingly, in various embodiments, the second cruise control mode may advantageously serve as a backup option in the event the wireless navigation signal and/or the road map data based is determined to be unavailable, thereby advantageously enhancing or improving reliability or effectiveness of cruise control, lo which in turn enhances driver experience of cruise control.

In various embodiments, the method 100 further comprises controlling a speed of the vehicle according to the final target vehicle speed information and/or displaying the final target vehicle speed information on a driver information interface. In other words, after the final target vehicle speed has been determined (e.g., corresponding to the target vehicle speed determined at 104 if no adjustment at 106 or the adjusted target vehicle speed if adjusted at 106), the speed of the vehicle may then be control according to the final target vehicle speed. Alternatively, or in addition thereto, the final target vehicle speed may be displayed to the driver so as to warn or alert the driver of the final target vehicle speed.

In various embodiments, the local perception sensor system comprises one or more of a camera-based perception sensor system, a radar-based perception sensor system, a sonar-based perception sensor and a lidar-based perception sensor system. In various embodiments, the local perception sensor system at least comprises a camera-based perception sensor system. These different types of perception sensor systems are known in the art, and thus need not be described herein in detail for clarity and conciseness.

In various embodiments, the vehicle is operating under cruise control. In particular, in various embodiments, the method 100 of controlling the vehicle for travelling on a curved road is advantageously able to continue to operate under cruise control effectively with vehicle speed management using only sensor data from the local perception sensor system of the vehicle (i.e., without a wireless navigation signal (e.g., a GNSS signal) and/or a road map database).

FIG. 2 depicts a schematic block diagram of a system 200 for controlling a vehicle for travelling on a curved road, according to various embodiments of the present invention, corresponding to the method 100 of a vehicle for travelling on a curved road as described hereinbefore with reference to FIG. 1 according to various embodiments of the present invention. The system 200 comprises: at least one lo memory 202; and at least one processor 204 communicatively coupled to the at least one memory 202 and configured to perform the method 100 of controlling a vehicle for travelling on a curved road as described hereinbefore with reference to FIG. 1 according to various embodiments of the present invention.

It will be appreciated by a person skilled in the art that the at least one processor 204 may be configured to perform various functions or operations through set(s) of instructions (e.g., software modules) executable by the at least one processor 204 to perform various functions or operations. Accordingly, as shown in FIG. 2, the system 200 may comprise a curvature determining module (or a curvature determining circuit) 206 configured to perform the above-mentioned determining (at 102) a curvature of the curved road based on first sensor data obtained by a local perception sensor system of the vehicle with respect to a surrounding environment; a target vehicle speed determining module (or a target vehicle speed determining circuit) 208 configured to perform the above-mentioned determining (at 104) a target vehicle speed for travelling on the curved road based on the curvature of the curved road determined; and a target vehicle speed adjusting module (or a target vehicle speed adjusting circuit) 210 configured to perform the above-mentioned determining (at 106) whether to adjust the target vehicle speed based on a lateral acceleration of the vehicle detected.

It will be appreciated by a person skilled in the art that the above-mentioned modules are not necessarily separate modules, and two or more modules may be realized by or implemented as one functional module (e.g., a circuit or a software program) as desired or as appropriate without deviating from the scope of the present invention. For example, two or more of the curvature determining module 206, the target vehicle speed determining module 208 and the target vehicle speed adjusting module 210 may be realized (e.g., compiled together) as one executable software program (e.g., software application or simply referred to as an "app"), which for example may be stored in the at least one memory 202 and executable by the at least one processor 204 to perform various functions/operations as described herein according to various embodiments of the present invention.

In various embodiments, the system 200 for controlling a vehicle corresponds to the method 100 of controlling a vehicle as described hereinbefore with reference to FIG. 1 according to various embodiments, therefore, various functions or operations configured to be performed by the least one processor 204 may correspond to various steps or operations of the method 100 of controlling a vehicle as described hereinbefore according to various embodiments, and thus need not be repeated with respect to the system 200 for controlling a vehicle for clarity and conciseness. In other words, various embodiments described herein in context of the method(s) are analogously valid for the corresponding system(s), and vice versa.

For example, in various embodiments, the at least one memory 202 may have stored therein the curvature determining module 206, the target vehicle speed determining module 208 and/or the target vehicle speed adjusting module 210, which respectively correspond to various steps (or operations or functions) of the method 100 of controlling a vehicle as described herein according to various embodiments, which are executable by the at least one processor 204 to perform the corresponding functions or operations as described herein.

According to various embodiments, there is provided a vehicle comprising: the system 200 as described hereinbefore with reference to FIG. 2 according to various embodiments; and the local perception sensor system as described hereinbefore communicatively coupled to the system 200 and configured to obtain sensor data with respect to a surrounding environment. It will be understood by a person skilled in the art that the present invention is not limited to any particular type of vehicle, as long as the vehicle is capable of travelling or being driven on a road, such as but not limited to, a car, a truck, a bus and so on.

A computing system, a controller, a microcontroller or any other system providing a processing capability may be provided according to various embodiments in the present disclosure. Such a system may be taken to include one or more processors and one or more computer-readable storage mediums. For example, the system 200 to for controlling a vehicle as described hereinbefore may include at least one processor (or controller) 204 and at least one computer-readable storage medium (or memory) 202 which are for example used in various processing carried out therein as described herein. A memory or computer-readable storage medium used in various embodiments may be a volatile memory, for example a DRAM (Dynamic Random Access Memory) or a non-volatile memory, for example a PROM (Programmable Read Only Memory), an EPROM (Erasable PROM), EEPROM (Electrically Erasable PROM), or a flash memory, e.g., a floating gate memory, a charge trapping memory, an MRAM (Magnetoresistive Random Access Memory) or a PCRAM (Phase Change Random Access Memory).

In various embodiments, a "circuit" may be understood as any kind of a logic implementing entity, which may be special purpose circuitry or a processor executing software stored in a memory, firmware, or any combination thereof. Thus, in an embodiment, a "circuit" may be a hard-wired logic circuit or a programmable logic circuit such as a programmable processor, e.g., a microprocessor (e.g., a Complex Instruction Set Computer (CISC) processor or a Reduced Instruction Set Computer (RISC) processor). A "circuit" may also be a processor executing software, e.g., any kind of computer program, e.g., a computer program using a virtual machine code, e.g., Java. Any other kind of implementation of the respective functions may also be understood as a "circuit" in accordance with various embodiments. Similarly, a "module" may be a portion of a system according to various embodiments and may encompass a "circuit" as described above, or may be understood to be any kind of a logic-implementing entity.

Some portions of the present disclosure are explicitly or implicitly presented in terms of algorithms and functional or symbolic representations of operations on data within a computer memory. These algorithmic descriptions and functional or symbolic representations are the means used by those skilled in the data processing arts to convey most effectively the substance of their work to others skilled in the art. An algorithm is here, and generally, conceived to be a self-consistent sequence of steps to leading to a desired result. The steps are those requiring physical manipulations of physical quantities, such as electrical, magnetic or optical signals capable of being stored, transferred, combined, compared, and otherwise manipulated.

Unless specifically stated otherwise, and as apparent from the following, it will be appreciated that throughout the present specification, description or discussions utilizing terms such as "determining", "detecting", "controlling", "displaying" or the like, refer to the actions and processes of a computer system, or similar electronic device, that manipulates and transforms data represented as physical quantities within the computer system into other data similarly represented as physical quantities within the computer system or other information storage, transmission or display devices.

The present specification also discloses a system (e.g., which may also be embodied as a device or an apparatus), such as the system 200 for controlling a vehicle, for performing various operations/functions of various methods described herein. Such a system may be specially constructed for the required purposes, or may comprise a general purpose computer or other device selectively activated or reconfigured by a computer program stored in the computer. The algorithms presented herein, if any, are not inherently related to any particular computer or other apparatus. Various general-purpose machines may be used with computer programs in accordance with the teachings herein. Alternatively, the construction of more specialized apparatus to perform various method steps may be appropriate.

In addition, the present specification also at least implicitly discloses a computer program or software/functional module, in that it would be apparent to the person skilled in the art that individual steps of various methods described herein may be put into effect by computer code. The computer program is not intended to be limited to any particular programming language and implementation thereof. It will be appreciated that a variety of programming languages and coding thereof may be used to implement the teachings of the disclosure contained herein. Moreover, the computer program is not intended to be limited to any particular control flow. There lo are many other variants of the computer program, which can use different control flows without departing from the scope of the invention. It will be appreciated by a person skilled in the art that various modules described herein (e.g., the curvature determining module 206, the target vehicle speed determining module 208 and/or the target vehicle speed adjusting module 210) may be software module(s) realized by computer program(s) or set(s) of instructions executable by a computer processor to perform the required functions, or may be hardware module(s) being functional hardware unit(s) designed to perform the required functions. It will also be appreciated that a combination of hardware and software modules may be implemented.

Furthermore, one or more of the steps of a computer program/module or method described herein may be performed in parallel rather than sequentially where appropriate. The computer program may be stored on any computer readable medium. The computer readable medium may include storage devices such as magnetic or optical disks, memory chips, or other storage devices suitable for interfacing with a computer. The computer program when loaded and executed on the computer effectively results in an apparatus that implements the steps of the methods described herein.

In various embodiments, there is provided a computer program product, embodied in one or more computer-readable storage mediums (non-transitory computer-readable storage medium(s)), comprising instructions (e.g., the curvature determining module 206, the target vehicle speed determining module 208 and/or the target vehicle speed adjusting module 210) executable by one or more computer processors to perform the method 100 of controlling a vehicle for travelling on a curved road, as described herein with reference to FIG. 1 according to various embodiments.

Accordingly, various computer programs or modules described herein may be stored in a computer program product receivable by a system therein, such as the system 200 for controlling a vehicle as shown in FIG. 2, for execution by at least one processor 204 of the system 200 to perform various functions.

lo Software or functional modules described herein may also be implemented as hardware modules. More particularly, in the hardware sense, a module is a functional hardware unit designed for use with other components or modules. For example, a module may be implemented using discrete electronic components, or it can form a portion of an entire electronic circuit such as an Application Specific Integrated Circuit (ASIC). Numerous other possibilities exist. Those skilled in the art will appreciate that the software or functional module(s) described herein can also be implemented as a combination of hardware and software modules.

In various embodiments, the system 200 for controlling a vehicle is, or is a part or component of, a cruise control system. The system 200 may be installed or installable in a vehicle. Accordingly, the system 200 for controlling a vehicle encompasses any cruise control system having at least one processor communicatively coupled to at least one memory and configured to perform the method 100 of controlling a vehicle for travelling on a curved road as described hereinbefore according to various embodiments (or at least comprising the curvature determining module 206, the target vehicle speed determining module 208 and the target vehicle speed adjusting module 210). As described in the background and mentioned hereinbefore, various cruise control technologies and systems are known in the art. Accordingly, it will be understood by a person skilled in the art that the cruise control system according to various embodiments of the present invention may be based on any type of cruise control system (e.g., advanced driver assistance system (e.g., adaptive cruise control) or autonomous driving system of level 2 or higher) as long as the cruise control system has at least one processor configured to perform the method 100 of controlling a vehicle for travelling on a curved road as described hereinbefore according to various embodiments.

It will be appreciated by a person skilled in the art that the terminology used herein is for the purpose of describing various embodiments only and is not intended to be limiting of the present invention. As used herein, the singular forms "a", "an" and "the" are intended to include the plural forms as well, unless the context clearly indicates otherwise. It will be further understood that the terms "comprises" and/or lo "comprising," when used in this specification, specify the presence of stated features, integers, steps, operations, elements, and/or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and/or groups thereof.

Any reference to an element or a feature herein using a designation such as "first", "second" and so forth does not limit the quantity or order of such elements or features, unless stated or the context requires otherwise. For example, such designations may be used herein as a convenient way of distinguishing between two or more elements or instances of an element. Thus, a reference to first and second elements does not necessarily mean that only two elements can be employed, or that the first element must precede the second element. In addition, a phrase referring to "at least one of" a list of items refers to any single item therein or any combination of two or more items therein.

In order that the present invention may be readily understood and put into practical effect, various example embodiments of the present invention will be described hereinafter by way of examples only and not limitations. It will be appreciated by a person skilled in the art that the present invention may, however, be embodied in various different forms or configurations and should not be construed as limited to the example embodiments set forth hereinafter. Rather, these example embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the present invention to those skilled in the art.

FIG. 3 depicts a schematic block diagram of a system 300 for controlling a vehicle for travelling on a curved road, according to various example embodiments of the present invention. In various example embodiments, the curved road may have a radius of curvature of 200 m or less. In various example embodiments, the curved road may have a radius of curvature of 50 m or less or 40 m or less, which may be considered as a tight (or sharp) curve. The system 300 comprises a curve detection module (or curve detection logic or circuit) 306 (e.g., corresponding to the curvature determining module 206 described hereinbefore according to various embodiments); io a target vehicle speed calculation module (or target vehicle speed calculation logic or circuit) 308 (e.g., corresponding to the target vehicle speed determining module 208 described hereinbefore according to various embodiments); and a target vehicle speed arbitration module (or target vehicle speed arbitration logic or circuit) 310 (e.g., corresponding to the target vehicle speed adjusting module 210 described hereinbefore according to various embodiments).

As shown in FIG. 3, when the system 300 is installed in a vehicle (not shown in FIG. 3), the curve detection module 306 may be communicatively coupled to a local perception sensor system 316 (which may also be referred to as an environmental sensor system comprising one or more environmental sensors) of the vehicle. In various example embodiments, the curve detection module 306 may be further communicatively coupled to one or more motion sensors 318 (e.g., an inertial measurement unit (IMU), a gyroscope and/or an accelerometer) installed in the vehicle. For example, the local perception sensor system 316 may comprise one or more of a camera-based perception sensor system, a radar-based perception sensor system, a sonar-based perception sensor and a lidar-based perception sensor system. In various example embodiments, the local perception sensor system 316 at least comprises a camera-based perception sensor system. The curve detection module 306 may be configured to determine a curvature of a curved road. In various example embodiments, the curve detection module 306 may be configured to determine a curvature of the curved road based on sensor data received from and obtained by the local perception sensor system 316. In various example embodiments, the sensor data comprises lane marking information. In this regard, the curvature of the curved road may be determined based on lane marking information in the sensor data obtained (or captured) by the local perception sensor system 316 of the vehicle with respect to the surrounding environment. For example, the local perception sensor system 316 may comprise at least a camera system configured to capture or sense visual information (i.e., images or videos) at least with respect to the surrounding environment ahead of the vehicle, such as of at least the road ahead of the vehicle (e.g., a section of the road directly or immediately ahead of the vehicle), such that the visual information captured include lane marking io information of the road ahead of the vehicle. It will be understood by a person skilled in the art that the above-mentioned section of the road directly or immediately ahead of the vehicle captured by the camera system depends on the arrangement or configuration (e.g., positions and orientations) of the camera system (e.g., including a plurality of camera sensors) on the vehicle. In this regard, the camera system may be arranged or configured such that at least the above-mentioned section of road directly or immediately ahead of the vehicle can be captured by the camera system (e.g., at least one or more camera sensors of the camera system arranged or configured as such). It will also be appreciated by a person skilled in the art that the present invention is not limited to any particular or specific distance or amount ahead of the vehicle to be captured by the camera system, which may be set as appropriate or as desired, as long as the above-mentioned visual information can be captured including lane marking information for determining the curvature of the curved road ahead of the vehicle. Therefore, the curvature of a road (or a section thereof) may be defined by, or determined with respect to, lane markers (or lane markings) along the road. Furthermore, it will be appreciated by a person skilled in the art that the present invention is not limited to any particular or specific manner in which the curvature of the curved road is determined based on lane marking information, as long as the curvature of the curved road is determined based on lane marking information, and thus, it is not necessary to describe herein in detail for clarity and conciseness.

As shown in FIG. 3, the target vehicle speed calculation module 308 may be communicatively coupled to the curve detection module 306. In various example embodiments, the target vehicle speed calculation module 308 may be configured to calculate or determine a target vehicle speed for travelling on the curved road based on the curvature of the curved road determined from the curve detection module 306. It will be appreciated by a person skilled in the art that the present invention is not limited to any particular or specific manner in which the target vehicle speed is determined based on the curvature of the curved road, as long as the target vehicle speed is determined based on the curvature of the curved road, and thus, it is not to necessary to describe herein in detail for clarity and conciseness. By way of an example only and without limitation, the target vehicle speed may be determined according to the following example formula based on uniform circular motion: Radius of curvature = Vt 2/ Ay, (Equation 1) where Vt denotes the target vehicle speed (m/s), Ay denotes a maximum lateral acceleration (m/s2) and the unit for radius of curvature is 'm' (i.e., meter). For example and without limitation, the maximum lateral acceleration for the vehicle not to exceed may be 2.5 m/s2 in view of an international regulation of 3.0 m/s2.

As shown in FIG. 3, the target vehicle speed arbitration module 310 may be communicatively coupled to the target vehicle speed calculation module 308 and the one or more motion sensors 318. In various example embodiments, the target vehicle speed arbitration module 310 may be configured to determine whether to adjust the target vehicle speed (determined by the target vehicle speed calculation module 308) based on a lateral acceleration of the vehicle detected by the one or more motions sensors 318 (e.g., an inertial measurement unit (IMU) a gyroscope and/or an accelerometer). In various example embodiments, the target vehicle speed may be decreased if the lateral acceleration of the vehicle detected is higher than a lateral acceleration threshold. As described hereinbefore, it will be understood by a person skilled in the art that the lateral acceleration threshold may be set as appropriate based on various factors, such as driver and/or passenger comfort level, safety level and/or applicable regulations. For example, if the lateral acceleration of the vehicle is determined to be higher than the lateral acceleration threshold, the amount of target vehicle speed to be reduced may be determined based on the amount by which the lateral acceleration exceeds the lateral acceleration threshold, such as but not limited to, a proportional amount. On the other hand, if the lateral acceleration of the vehicle is determined to be not higher than the lateral acceleration threshold (e.g., lower than the lateral acceleration threshold), the target vehicle speed determined by the target vehicle speed calculation module 308 may then be maintained (i.e., no adjustment) unless the target vehicle speed is higher than the set cruise control vehicle speed (e.g., as set by the driver) (of which the to target vehicle speed may then be decreased to the set cruise control vehicle speed). In various example embodiments, the target vehicle speed arbitration module 310 may further be communicatively coupled to the local perception sensor system 316 of the vehicle for detecting the curved road at a distance ahead of the vehicle based on sensor data obtained by the local perception sensor system 316 as described hereinbefore and will be further described later below with reference to FIG. 5 (i.e., corresponding to the first stage 502 shown in FIG. 5).

As shown in FIG. 3, the target vehicle speed arbitration module 310 may be configured to control the speed of the vehicle according to a final target vehicle speed determined (e.g., corresponding to the target vehicle speed determined by the target vehicle speed calculation module 308 if no adjustment or the adjusted target vehicle speed if adjusted by the target vehicle speed arbitration module 310) by outputting the final target vehicle speed information (indicating the final target vehicle speed determined) to an actuator device or system 322 for implementing the speed of the vehicle (or set the cruise control vehicle speed) according to the final target vehicle speed information. Alternatively, or in addition thereto, the final target vehicle speed information may be displayed to the driver on a driver information interface 324 (e.g., a human machine interface (HMI) warning device) so as to warn or alert the driver of the final target vehicle speed.

FIG. 4 depicts a schematic flow diagram of a method 400 of controlling a vehicle for travelling on a curved road using at least one processor, according to various example embodiments of the present invention, corresponding to the system 300 for controlling a vehicle for travelling on a curved road, according to various example embodiments of the present invention.

At 402 and 404, the curve detection module 306 may detect whether the road ahead of the vehicle is a curved road (e.g., a corresponding section of the road directly or immediately ahead of the vehicle that is captured (or sensed) in sensor data by the local perception system of the vehicle (e.g., a camera system configured to at least capture or sense a surrounding environment ahead of the vehicle)). In this regard, io the curve detection module 306 may determine a curvature of the road based on lane marking information in the sensor data obtained (or captured) by the local perception sensor system 316 of the vehicle, and determine whether the curvature of the road meets a minimum degree of curvature (e.g., radius of curvature of 200 m or less) for the road ahead to be considered (or determined) as a curved road (or for the corresponding section of the road ahead to be part of a curved road). If the curve detection module 306 determines that the road ahead of the vehicle is a curved road, at 406, the target vehicle speed calculation module 310 may calculate or determine a target vehicle speed for travelling on the curved road based on the curvature of the curved road determined from the curve detection module 306. On the other hand, if the curve detection module 306 does not detect that the road ahead of the vehicle is a curved road, at 408, the cruise control speed set by the driver or dynamically adjusted based on adaptive cruise control with respect to a preceding vehicle, or the cruise control speed automatically set in the case of an autonomous vehicle, may be implemented. At 410, if a curved road ahead of the vehicle is detected and a target vehicle speed for travelling on the curved road is determined, the target vehicle speed arbitration module 310 may determine whether to adjust the target vehicle speed (determined by the target vehicle speed calculation module 308) based on a lateral acceleration of the vehicle detected by the one or more motions sensors 318. Thereafter, the target vehicle speed arbitration module 310 may output a final target vehicle speed information to an actuator system 322 for implementing the speed of the vehicle according to the final target vehicle speed information and/or to a driver information interface 324 for display to a driver so as to warn or alert the driver of the final target vehicle speed.

In various example embodiments, the curve detection at 402 and 404, the target vehicle speed calculation at 406 and the target vehicle speed arbitration at 410 may be performed in an iterative loop until the curve detection at 402 and 404 does not detect (or no longer detects) a curved road ahead (e.g., immediately ahead) of the vehicle. Accordingly, the iterative loop may be continuously performed while the vehicle is travelling (or cruising) along the curved road under cruise control, thereby to determining the target vehicle speed and determining whether to adjust the target vehicle speed at each corresponding iteration along the curved road. Accordingly, in various example embodiments, at each iteration, the curve detection at 402 and 404, the target vehicle speed calculation at 406 and the target vehicle speed arbitration at 410 may be performed with respect to a corresponding section or part of the curved road (e.g., a corresponding section of the curved road directly or immediately ahead of the vehicle that is captured (or sensed) by the local perception system of the vehicle (e.g., a camera system configured to at least capture or sense a surrounding environment ahead of the vehicle)).

Accordingly, the system 300 is advantageously configured to control the vehicle for travelling on a curved road based on sensor data obtained from a local perception sensor system 316 without a wireless navigation signal (e.g., a GNSS signal) and/or a road map database. For example, as described above, the sensor data may be obtained based on road sign detection and road curvature detection. In various example embodiments, the sensor data may further be obtained from preceding vehicle detection.

For example, lane markers or landmarks (e.g., speed limit sign), surrounding objects may be detected by environmental sensors, which enables Adaptive Cruise Control (ACC) and Lane Keep Assist (LKA) with the cruise control vehicle speed set by the driver. However, for a tight curve (e.g., radius of curvature less than 50 m), deceleration to slower vehicle speed than the set cruise control vehicle speed may be required for comfort and safety. In this regard, various example embodiments of the present invention advantageously controls the vehicle for travelling on a curved road, including a tight curve, based on the local perception sensor system 316 of the vehicle to realise a smooth and natural cruise control for the driver. It will be understood by a person skilled in the art that the cruise control system according to various example embodiments of the present invention may be based on any type of cruise control system (e.g., advanced driver assistance system (e.g., adaptive cruise control) or autonomous driving system of level 2 or higher).

to For better understanding, an illustrative scenario of a vehicle 501 approaching a curved road and travelling along the curved road will now be described with reference to FIG. 5 according to various example embodiments of the present invention, by way of an example only and without limitation.

At a first stage 502, the vehicle 501 may detect a curved road at a distance ahead based on sensor data obtained by the local perception sensor system 316 of the vehicle 501 with respect to the surrounding environment. For example, one or more road curve signs 503 may be located at a distance ahead of an upcoming curved road. As illustrated in FIG. 5, the vehicle 501 may reach a point on the road whereby its local perception sensor system 316 captures the one or more road curve signs 503 in the form of sensor data. It will be appreciated by a person skilled in the art that although FIG. 5 illustrates a road curve sign 503 on a side of the road, road curve sign(s) may also be in the form as road marking(s) on the road or in any other form or location (e.g., hanging over a road) as appropriate. In addition, the local perception sensor system 316 of the vehicle 501 may also capture one or more speed limit signs 504 for the curved road ahead in the form of sensor data. Similarly, although FIG. 5 illustrates a speed limit sign 503 on a side of the road, speed limit sign(s) may also be in the form as road marking(s) on the road or in any other form or location (e.g., hanging over a road) as appropriate. Upon detecting the curved road at a distance ahead and the corresponding speed limit based on sensor data obtained by the local perception sensor system 316, the system 300 may then determine whether to adjust a set cruise control vehicle speed (e.g., set by the driver). In this regard, the set cruise control vehicle speed may be decreased to the speed limit detected for the curved road if the set cruise control vehicle speed is higher than the speed limit, thereby decreasing the current vehicle speed to the speed limit indicated by the speed limit sign.

In various example embodiments, the curved road at a distance ahead of the vehicle 501 may be determined further based on additional sensor data. For example, deceleration information, travelled path curvature information and/or other kinematic information of a preceding vehicle may be obtained for more robust situation lo interpretation or awareness. For example, the deceleration information and the travelled path curvature information of the preceding vehicle can be obtained based on sensor data from the local perception sensor system 316, such as from a radar-based perception sensor system and/or a lidar-based perception sensor system thereof. For example, detecting that a preceding vehicle is decelerating and curving along a path may further indicate that a curved road is ahead.

At a second stage 506, the vehicle 501 may reached just before the curved road and the system 300 may detect a start of the curved road based on sensor data obtained by the local perception sensor system 316 with respect to the surrounding environment. In this regard, the sensor data may comprise lane marking information.

Accordingly, the start of the curved road may be determined based on lane marking information in the sensor data obtained (or captured) by the local perception sensor system 316, and more particularly, at least with respect to the surrounding environment ahead of the vehicle 501, such as of at least the road ahead of the vehicle 501 (e.g., a section of the road directly or immediately ahead of the vehicle 501), such that the visual information captured include lane marking information of the road ahead of the vehicle 501. For example, the start of the curved road may be determined based on the commencement of the curvature of the curved road as determined based on the lane marking information in the sensor data obtained. In various example embodiments, the system 300 may also determine whether to adjust or further adjust the set cruise control vehicle speed for entering the curved road based on the sensor data. In this regard, a curvature of the curved road may be determined (e.g., in the same or similar manner as described hereinbefore with respect to the curve detection module 306), and a target vehicle speed may then be determined for travelling on the curved road based on the curvature of the curved road determined (e.g., in the same or similar manner as described hereinbefore with respect to the above-mentioned target vehicle speed calculation module 308). The set cruise control vehicle speed may then be adjusted (or further adjusted if it was already adjusted as described hereinbefore at the first stage 502 when the vehicle 501 was at a distance ahead of the curved road) based on the target vehicle speed determined.

At a third stage 508, the vehicle 501 may be travelling along the curved road. At this stage, the method 400 of controlling a vehicle 501 for travelling on a curved road as described with reference to FIG. 4 may be performed. In particular, the curve detection at 402 and 404, the target vehicle speed calculation at 406 and the target vehicle speed arbitration at 410 may be performed in an iterative loop until the curve detection at 402 and 404 does not detect (or no longer detects) a curved road ahead (e.g., a section of the road directly or immediately ahead) of the vehicle 501, such as until at the fourth stage 510 shown in FIG. 5. Accordingly, while the vehicle 501 is travelling along the curved road, the system 300 may continuously monitor the curvature of the road using the local perception sensor system 316 and continuously monitor the lateral acceleration of the vehicle 501 using the motion sensor(s) 318.

At a fourth stage 510, the vehicle 501 may reach the end of the curved road, which may be detected by the curve detection module 402 (i.e., no longer detects a curved road ahead of the vehicle 501). The speed of the vehicle 501 may then be set to the cruise control speed originally set by the driver or dynamically adjusted based on adaptive cruise control with respect to a preceding vehicle, or the cruise control speed automatically set in the case of an autonomous vehicle.

Accordingly, controlling a vehicle 501 for travelling on a curved road according to various example embodiments of the present invention has advantageously been found to enhance or improve reliability or effectiveness of cruise control, and more particularly, for curved roads, thereby enhancing driver experience of cruise control. In particular, the curved road is detected and the curvature of the curved road is determined based on sensor data obtained by the local perception sensor system 316 of the vehicle 501 with respect to a surrounding environment. As a result, the vehicle 501 operating under cruise control is able to continue to operate effectively with vehicle speed management for travelling on a curved road regardless of the availability of a wireless navigation signal (e.g., a GNSS signal) and/or a road map database (e.g., at a remote server) (e.g., vehicle in a GNSS denied environment), thereby advantageously enhancing or improving reliability or effectiveness of cruise to control, which in turn enhances driver experience of cruise control (e.g., enable a smooth and natural cruise control experience for the driver). In various example embodiments, controlling the vehicle 501 for travelling on a curved road based on the local perception sensor system 316 (without a GNSS signal and/or accessibility to a road map database) may be performed as a backup option in the event the wireless navigation signal and/or the road map data based is determined to be unavailable, thereby advantageously enhancing or improving reliability or effectiveness of cruise control.

While embodiments of the invention have been particularly shown and described with reference to specific embodiments, it should be understood by those skilled in the art that various changes in form and detail may be made therein without departing from the scope of the invention as defined by the appended claims. The scope of the invention is thus indicated by the appended claims.

REFERENCE SIGNS

200: System for Controlling a Vehicle 202: Memory 204: Processor 206: Curvature Determining Module 208: Target Vehicle Speed Determining Module 210: Target Vehicle Speed Adjusting Module lo 300: Example System for Controlling a Vehicle 306: Curve Detection Module 308: Target Vehicle Speed Calculation Module 310: Target Vehicle Speed Arbitration Module 316: Local Perception Sensor System 318: Motion Sensor(s) 322: Actuator Device 324: Driver Information Interface 501: Vehicle 502: Stage 1 503: Road Curve Sign 504: Speed Limit Sign 506: Stage 2 508: Stage 3 510: Stage 4

Claims

CLAIMS1. A method (100, 400) of controlling a vehicle (501) for travelling on a curved road using at least one processor (204), the method (100, 400) comprising: determining (102, 402, 404) a curvature of the curved road based on first sensor data obtained by a local perception sensor system (316) of the vehicle (501) with respect to a surrounding environment; determining (104, 406) a target vehicle speed for travelling on the curved road io based on the curvature of the curved road determined; and determining (106, 410) whether to adjust the target vehicle speed based on a lateral acceleration of the vehicle (501) detected.
2. The method (100, 400) according to claim 1, wherein said determining (106, 410) whether to adjust the target vehicle speed comprises: determining whether the lateral acceleration of the vehicle (501) detected is higher than a lateral acceleration threshold; and decreasing the target vehicle speed based on determining that the lateral acceleration of the vehicle (501) detected is higher than the lateral acceleration 20 threshold.
3. The method (100, 400) according to claim 1 or 2, wherein said determining (102, 402, 404) the curvature of the curved road, said determining (104, 406) the target vehicle speed and said determining (106, 410) whether to adjust the target vehicle speed are performed in an iterative loop until a curvature of a road ahead of the vehicle (501) is determined to be less than a curvature threshold.
4. The method (100, 400) according to claim 3, wherein the iterative loop further comprises outputting final target vehicle speed information after said determining (106, 410) whether to adjust the target vehicle speed.
5. The method (100, 400) according to any one of claims 1 to 4, wherein the first sensor data comprises lane marking information.
6. The method (100, 400) according to any one of claims 1 to 5, wherein the method (100, 400) further comprises: detecting the curved road at a distance ahead of the vehicle (501) based on second sensor data obtained by the local perception sensor system (316) of the vehicle (501) with respect to the surrounding environment; and determining whether to adjust a set cruise control vehicle speed based on the ro second sensor data.
7. The method (100, 400) according to claim 6, wherein the second sensor data comprises road sign information (503, 504).
8. The method (100, 400) according to claim 7, wherein the road sign information (503, 504) comprises speed limit information (504) for the curved road, and said determining whether to adjust the set cruise control vehicle speed comprises: determining whether the set cruise control vehicle speed is higher than a speed limit indicated by the speed limit information (504); and decreasing the set cruise control vehicle speed based on determining that the set cruise control vehicle speed is higher than the speed limit indicated by the speed limit information (504).
9. The method (100, 400) according to claim 7 or 8, wherein: the road sign information (503, 504) further comprises road curve sign information (503) for the curved road, and the curved road at the distance ahead of the vehicle (501) is detected based on the road curve sign information (503).
10. The method (100, 400) according to any one of claims 6 to 9, wherein the method (100, 400) further comprises: detecting a start of the curved road based on third sensor data obtained by the local perception sensor system (316) of the vehicle (501) with respect to the surrounding environment; and determining whether to adjust or further adjust the set cruise control vehicle speed for entering the curved road based on the third sensor data.
11. The method (100, 400) according to claim 10, wherein the third sensor data to comprises lane marking information.
12. The method (100, 400) according to any one of claims 1 to 11, wherein: the method (100, 400) further comprises determining availability of a wireless navigation signal and/or a road map database, and said determining (102, 402, 404) the curvature of the curved road, said determining (104, 406) the target vehicle speed and said determining (106, 410) whether to adjust the target vehicle speed are performed for the curved road based on determining that the wireless navigation signal and/or the road map database is unavailable
13. The method (100, 400) according to claim 4, wherein the method (100, 400) further comprises controlling a speed of the vehicle (501) according to the final target vehicle speed information and/or displaying the final target vehicle speed information on a driver information interface (324).
14. The method (100, 400) according to any one of claims 1 to 13, wherein the local perception sensor system (316) comprises one or more of a camera-based perception sensor system, a radar-based perception sensor system, a sonar-based perception sensor and a lidar-based perception sensor system.
15. The method (100, 400) according to any one of claims 1 to 14, wherein the vehicle (501) is operating under cruise control.
16. A system (200, 300) for controlling a vehicle (501) for travelling on a curved road, the system comprising: at least one memory (202); and at least one processor (204) communicatively coupled to the at least one memory (202) and configured to perform the method (100, 400) according to any one of claims 1 to 15.
17. A vehicle (501) comprising: the system (200, 300) according to claim 16; and a local perception sensor system (316) communicatively coupled to the system (200, 300) and configured to obtain sensor data with respect to a surrounding environment.
18. A computer program product, embodied in one or more non-transitory computer-readable storage mediums, comprising instructions executable by at least one processor (204) to perform the method (100, 400) according to any one of claims 1 to 15.