DE102022103430A1 - Method and control arrangement for controlling the speed of a vehicle - Google Patents

Abstract

The invention relates to a method for controlling a cruise control of a vehicle, the method comprising: determining a maximum speed profile, v _max , and a minimum speed profile, v _min , for an upcoming road section based on information about the upcoming road section; and controlling the speed controller such that a speed of the vehicle in the upcoming road segment is in a speed interval between the maximum speed profile and the minimum speed profile. This enables the cruise control to control the vehicle's speed in a versatile, safe, reliable and energy-efficient manner based on the prevailing road conditions. The invention also relates to a control arrangement, a vehicle with the control arrangement, a computer program and a computer-readable medium.

Description

TECHNICAL AREA

The invention relates to a method and a control arrangement for controlling a cruise control in a vehicle. The invention also relates to a computer program, a computer-readable medium and a vehicle with such a control arrangement.

BACKGROUND

The following description of principles explains the background of the invention, but does not necessarily define the prior art.

One of the global challenges these days is reducing the negative impact of road transport on the environment. The energy consumption in vehicles is also associated with costs for the vehicle owner. In vehicles equipped with an internal combustion engine, the cost of fuel represents a significant expense for the vehicle owner or user. In vehicles equipped with electric motors, the efficiency of the vehicle's energy consumption is a major factor in the cost, performance and competitiveness of the vehicle.

This has increasingly led to efforts to improve the energy efficiency of vehicles. Reduced energy consumption can be achieved, for example, by means of cruise control functions, where the vehicle's actual speed may deviate from a speed set by the driver. Cruise control functions, also known as so-called predictive cruise controls, use look-ahead information to control the vehicle's speed in an energy-efficient manner.

BRIEF DESCRIPTION

It is an aim of embodiments of the invention to mitigate or overcome at least some of the disadvantages of the prior art.

Thus, a goal is to provide a solution related to the control of a cruise control in a vehicle for energy-efficient vehicle propulsion.

• Bestimmen eines Maximalgeschwindigkeitsprofils und eines Minimalgeschwindigkeitsprofils für einen anstehenden Straßenabschnitt auf Basis von Informationen über den anstehenden Straßenabschnitt; und

According to a first variant of the invention, the above and other objectives are achieved with a method for controlling a speed controller of a vehicle, the method having:

• determining a maximum speed profile and a minimum speed profile for an upcoming road segment based on information about the upcoming road segment; and

Controlling the cruise controller such that a speed of the vehicle in the upcoming road segment is controlled in a speed interval lying between the maximum speed profile and the minimum speed profile.

In other words: the invention relates to a method for controlling the speed of a vehicle by means of a speed control function which uses information about the upcoming road section in order to dynamically define a permissible speed interval at any time.

By determining the maximum speed profile and the minimum speed profile on the basis of information relating to the upcoming road section, a permissible speed interval is defined at any point in time. Instead of setting a static speed interval, as in conventional cruise control functions, the permitted speed interval according to the invention can be adapted to the prevailing road conditions and to changing surroundings of the vehicle.

By controlling the cruise control according to the present invention to adjust a speed of the vehicle in the upcoming road section, the speed of the vehicle can be controlled in a safe and reliable manner. In driving situations with different external factors influencing the speed of the vehicle, the cruise controller is able to use different types of speed profiles, e.g. constant speed profiles, more complex speed profiles that vary continuously, as well as speed profiles that allow transitions between different speed levels. This makes it more attractive for the driver to use the cruise control function to control the speed of the vehicle, even in situations that are not well suited to the use of conventional cruise control functions, ie in situations where the permitted speed interval can be expected to change dynamically changes. For example, the driver does not have to switch off the cruise control function when driving a car off the train, rather he can leave them on, even on secondary roads and in urban areas, which leads to an increased use of energy-saving functions of the cruise control compared to conventional cruise control.

Due to the reduced energy consumption in the vehicles, costs are reduced. Furthermore, in vehicles equipped with an internal combustion engine, reduced energy consumption leads to reduced exhaust emissions from the vehicle due to reduced fuel consumption.

In vehicles equipped with electric motors, reduced energy consumption leads to reduced wear and tear on components in the vehicle's drive train, e.g. with regard to the battery supplying the one or more electric motors, since the permitted speed interval can be selected in such a way that a reduced power draw is achieved of the battery is made possible by energy-efficient driving.

In an embodiment of the invention, the method includes a determination of the maximum speed profile also based on user input in the speed controller.

With this, the maximum speed profile can be determined on the basis of the driving preferences of the driver. A speed control that gives the driver the ability to control the speed and details of execution is more attractive to drivers than a speed control that does not have this capability.

Thus, the driving experience for the driver of the vehicle can be extended and this gives a competitive advantage to the cruise control according to the invention.

In an embodiment of the invention, the method includes determining the minimum speed profile based also on an input to the speed controller.

This achieves similar advantages as when determining the maximum speed profile on the basis of an input into the speed controller.

In one embodiment of the invention, the user input to the cruise control is a user input in driver mode.

Thus, the permitted speed of the vehicle can be related to a user/driver mode selected by the driver of the vehicle. The driver mode here can refer to one or more default execution settings in the vehicle speed controller, where the speed of the vehicle is determined based on the selected setting. The driver is thus given flexibility with which he can determine priority with regard to, for example, fuel/energy consumption and travel time. The driver's preferences for driving the vehicle are thus taken into account in controlling the speed of the vehicle.

This achieves personalized speed control, which enables the driver to adapt the vehicle's behavior to their individual preferences in terms of functionality and speed.

The permitted speed of the vehicle can also be set by the user in a simple and intuitive manner.

In an exemplary embodiment of the invention, the determination of the maximum speed profile is also based on a set speed profile with regard to the upcoming road section.

Here, a set speed may include a speed to be maintained by the vehicle. The set speed can be set by the driver or it can be automatically based on, for example, speed limit information.

The speed of the vehicle thus corresponds to the prescribed vehicle speed in an improved manner.

In an exemplary embodiment of the invention, the minimum speed profile is also determined on the basis of a set speed profile for the upcoming road section.

This achieves similar advantages as when determining the maximum speed profile, also taking into account the set speed profile with regard to the upcoming road section.

In one embodiment of the invention, the maximum speed profile and the minimum speed profile have different accelerations and/or different decelerations.

If the maximum speed profile and the minimum speed profile have different accelerations and/or different decelerations, the course of the permitted speed interval can be adjusted in such a way that the behavior of the vehicle is optimized. Such a variable permitted speed interval can prove beneficial in a number of situations. For example, a large allowed speed interval may give the cruise controller a better chance of determining vehicle speed in accordance with, for example, preferred driving style and road conditions. Energy-efficient driving can be achieved, for example, by braking, engine braking, coasting, etc., depending on the permitted speed interval and road conditions. A narrow allowed speed interval does not give the same opportunities for speed variation, but can be a good option in situations where smaller speed variations are preferred or required.

In an embodiment of the invention, the maximum speed profile and the minimum speed profile have different starting positions with regard to acceleration and/or deceleration.

With this, the permissible speed interval of the vehicle is determined in such a way that the speed of the vehicle can be adapted to the given road conditions, changing surroundings of the vehicle and also to the driving preferences of the driver.

In an embodiment of the invention, the maximum speed profile and the minimum speed profile have different stop positions with respect to acceleration and/or deceleration.

With this, in a manner similar to that described above, the permissible speed interval of the vehicle can be determined so that the speed of the vehicle can be adapted to the given road conditions, to changing surroundings of the vehicle and also to the driving preferences of the driver.

In one embodiment of the invention, the maximum velocity profile and/or the minimum velocity profile include intervals of constant velocity.

Such constant speed intervals can, for example, be used in sections, i.e. they are speed intervals which have a constant speed over a time interval.

The maximum speed profile and/or the minimum speed profile can thus be adapted to the driving preference of the driver when transitioning from an interval of constant speed to an interval with a different constant speed. This can occur, for example, when driving on a road where the speed limits are changing.

By defining speed profiles with constant speed intervals, e.g. with link-wise constant speed intervals, efficient algorithms can be used that require less computational effort compared to algorithms used to determine more complex speed intervals. Thus, the speed intervals can be determined in a quick and efficient manner.

Also, constant speed intervals can be easier for the driver to understand compared to more complex intervals, which is particularly advantageous when the speed intervals are related to driver preferences.

In one embodiment of the invention, the maximum speed profile and/or the minimum speed profile includes continuously varying speed intervals.

A speed interval can thus be adapted to the driver's driving preferences in certain situations in which, for example, the prevailing road conditions and/or the vehicle environment are undergoing continuous change. This can occur, for example, when the maximum safe speed on a curve changes with the curvature of the curve.

In one embodiment of the invention, the information regarding the upcoming road section includes information regarding at least one of the following variables: a speed limit, traffic density, traffic information, a curvature, a bank angle, a topography, and visibility conditions.

The speed of the vehicle is thus adapted to the prevailing road conditions and a changing vehicle environment.

• Bestimmen eines Maximalgeschwindigkeitsprofils und eines Minimalgeschwindigkeitsprofils für einen anstehenden Straßenabschnitt auf Basis von Informationen über den anstehenden Straßenabschnitt; und

According to a second variant, the invention relates to a control arrangement for controlling a cruise control of a vehicle, the control arrangement being set up to carry out the following:

• determining a maximum speed profile and a minimum speed profile for an upcoming road segment based on information about the upcoming road segment; and

Controlling the speed controller in such a way that the speed of the vehicle in the upcoming section of road lies in a speed interval between the maximum speed profile and the minimum speed profile.

According to a third variant of the invention, the above and other objects are achieved with a vehicle having a control arrangement according to the second variant.

According to a fourth variant, the invention relates to a computer program with instructions which, when the program is executed by a computer, cause the latter to execute a method according to the first variant.

According to a fifth variant, the invention relates to a computer-readable medium with instructions which, when executed by a computer, cause the latter to execute the method according to the first variant.

character list

• 1 zeigt ein Fahrzeug, in dem Ausführungsbeispiele der Erfindung verwirklicht sind.
• 2 zeigt ein Flussdiagramm für ein Verfahren zum Steuern eines Geschwindigkeitsreglers eines Fahrzeuges gemäß Ausführungsbeispielen der Erfindung.
• 3a erläutert ein Beispiel für die Geschwindigkeitssteuerung in einem Fahrzeug mit Geschwindigkeitsvariationen in diskreten Schritten gemäß Ausführungsbeispielen der Erfindung.
• 3b erläutert ein Beispiel für eine Geschwindigkeitssteuerung in einem Fahrzeug mit einer kontinuierlichen Geschwindigkeitsvariation gemäß Ausführungsbeispielen der Erfindung.
• 4 erläutert ein Beispiel für eine Geschwindigkeitssteuerung in einem Fahrzeug gemäß Ausführungsbeispielen der Erfindung.
• 5a-5c zeigen Beispiele für Übergänge zwischen verschiedenen Sätzen von Geschwindigkeitsprofilen.
• 6 zeigt eine Steueranordnung eines Fahrzeuges gemäß 1 gemäß Ausführungsbeispielen der Erfindung.

Embodiments of the invention will now be explained in detail with a view to the accompanying figures, in which similar reference numbers refer to similar components:

• 1 FIG. 12 shows a vehicle in which embodiments of the invention are implemented.
• 2 FIG. 1 shows a flow chart for a method for controlling a cruise control of a vehicle according to exemplary embodiments of the invention.
• 3a 12 illustrates an example of speed control in a vehicle with speed variations in discrete steps according to embodiments of the invention.
• 3b 12 illustrates an example of speed control in a vehicle with continuous speed variation according to embodiments of the invention.
• 4 12 explains an example of speed control in a vehicle according to embodiments of the invention.
• 5a-5c show examples of transitions between different sets of velocity profiles.
• 6 shows a control arrangement of a vehicle according to FIG 1 according to embodiments of the invention.

DESCRIPTION OF DETAILS

A predictive cruise control uses predictive information to control the vehicle's speed in an energetically efficient manner. In contemporary predictive (predictive) speed controllers, the driver usually determines a set speed, vset, as well as the size of an interval according to which the variations (changes) in relation to the set speed are allowed, ie _vmin , _vmax . Within the interval around the set speed v _set , the predictive cruise controller controller determines an energy efficient internal reference speed v _ref to be maintained by the vehicle. The reference speed v _ref is used as a reference for low-level speed controls. Typical look-ahead information for determining v _ref is road topography.

However, if the set speed vset changes due to, for example, changing speed limits or road curvatures, the speed of the vehicle must be adjusted with a transition from one set speed to another. In conventional solutions the driver can set different fixed values for desired accelerations and decelerations when the setting speed varies between two different constant values. However, it is often not energy efficient to transition between different set speeds with a fixed constant rate of acceleration and deceleration. Setting fixed values for desired accelerations and decelerations also does not solve the problem if the changes in speed are not made in discrete steps, as in the case of constant speed limitations. For example, when driving on winding roads, the maximum permitted speed can vary continuously and not between incrementally constant values.

Therefore, an improved method for controlling a speed controller is to be sought of a vehicle to overcome the problems of conventional solutions.

1 is used here to explain exemplary embodiments described here. 1 shows schematically an example vehicle 100. There are in 1 only those units/equipment/variables of the vehicle 100 that are helpful for understanding the invention are shown. The vehicle 100 according to FIG 1 has a drive train/power transmission 110 that is set up to transmit torque between at least one drive unit 101 and drive wheels 111, 112 of vehicle 100. The at least one drive unit 101 can contain an internal combustion engine that is connected in a conventional manner via an output shaft 101 of drive unit 101 to a clutch 103 and also to a transmission 105 via the clutch. The torque provided by the drive unit 101 is then applied to the input shaft 104 of the transmission 105 . A drive shaft 106 connected to an output shaft of the transmission 105 drives the drive wheels 111,112 through a central transmission 107, such as a conventional differential, and drive shafts 104,105 connected to the central transmission 107.

In addition to the drive unit 101 having an internal combustion engine, the vehicle 100 can also have one or more electric machines for driving the drive wheels 111, 112 of the vehicle 100; it can therefore be a so-called hybrid vehicle, for example.

In another example, the drive unit 101 may contain only electric machines for driving the drive shaft 111, 112, such that the vehicle 100 is an all-electric vehicle.

The one or more electric machines may be located substantially anywhere along the drive train 110 as long as torque is transferred to one or more of the wheels 111,112. The vehicle 100 may be configured in any known manner, such as without the transmission 104 or a conventional differential as shown in FIG 1 without thereby limiting the scope of the invention.

The powertrain/transmission 110 and its components are controlled by the vehicle control system via at least one control assembly 120 in which the described invention may be implemented. The at least one control arrangement 120 is responsible, for example, for one or more cruise control functions for automatically controlling the speed of the vehicle. These cruise control functions can be of different types. In one example, the cruise control function is conventional and configured to maintain a speed set by the driver or the system. The cruise control function can also be such that additional information is used to control the speed of the vehicle. For example, the cruise control function can perform a so-called "look-ahead" function. A "look-ahead" cruise control (LACC) includes a cruise control function that uses knowledge of an upcoming road segment, i.e. knowledge of the topography of the road ahead of the vehicle, to adjust vehicle speed based on variations in the road the vehicle is traveling on.

The control arrangement 120 can be distributed over a plurality of control units that are set up to control different components of the vehicle 100. The control arrangement 120 can have, for example, a determination unit 121 for a speed profile and a speed control unit 122 that is set up to carry out the method steps of the invention described, such as it is explained in more detail below. The control arrangement 120 is described in more detail in 6 described.

The vehicle 100 may further include at least one sensor 140, such as a camera, located at a suitable location on the vehicle 100.

Furthermore, the vehicle 100 can have a positioning system/unit 150 . The positioning unit 150 may be based on a satellite navigation system such as a Navigation Signal Timing and Ranging (Navstar), a Global Positioning System (GPS), a Differential GPS (DGPS), Galileo, GLONASS, or the like. Thus, the positioning unit can have a GPS receiver.

The vehicle 100 can further have at least one communication device 160 that is set up for communication with at least one unit 170 that is external to the vehicle 100, such as an infrastructure device, an external server, a device for position information and/or at least one communication device of another vehicle.

According to various embodiments of the invention, the at least one communication device 160 may be essentially any device that transmits information to and/or from Vehicle 100 transmits, and the at least one device 170 external to the vehicle 100 may essentially be any external device that communicates with the vehicle 100, ie with the at least one communication device 160, for the transmission of information to and/or from vehicle 100. The at least one communication device 160 can also be a vehicle-to-vehicle communication device (V2V), a communication device for vehicle-to-infrastructure communication (V2I), a vehicle-to-all (V2X) communication device and /or a wireless communication device such that communication between the vehicle 100 and the at least one external device 170 is achieved/provided.

The proposed solution will now be discussed in more detail with reference to 2 described, which shows a flowchart for a method 200 for controlling a cruise control of a vehicle. The method 200 has steps 210-220.

In step 210 according to 2 determining a maximum speed profile and a minimum speed profile for an upcoming road segment based on information regarding the upcoming road segment; and
in step 220 the cruise control is controlled to regulate a speed of the vehicle 100 in the upcoming road segment in a speed interval between the maximum speed profile and the minimum speed profile.

The in step 210 according to 2 Certain maximum and minimum speed profiles can indicate a permitted speed interval of the vehicle over the time in which the vehicle is driving on the upcoming road section. Such maximum and minimum speed profiles may be used in a conventional manner by the vehicle's cruise control to determine vehicle speed.

By controlling the speed controller such that a speed of the vehicle in the upcoming road section is controlled in a speed interval between the maximum speed profile and the minimum speed profile according to step 220 in 2 results in a vehicle speed in the safe, reliable range with energy efficiency. This is significant in a number of situations, such as in the 3a and 3b is shown.

3a 10 shows a non-limiting example of controlling the speed of a vehicle 100 according to embodiments of the invention. The speed of the vehicle 100 in 3a can fluctuate between times T1 and T2 within a permitted deviation between a first maximum speed profile v _{max_1} and a first minimum speed profile v _{min_1} . The first maximum speed profile v _{max_1} and the first minimum speed profile v _{min_1} can be determined here according to method 200 on the basis of information about the upcoming road section.

As a non-limiting example, the vehicle 100 may be driven on a freeway and the information regarding the upcoming road segment may be a speed limit related to the portion of the freeway. In another example, the information regarding the upcoming road section can be a combination of a currently given speed limit and information regarding the currently given weather conditions and/or given visibility conditions. As will be explained further, the maximum speed profiles and the minimum speed profiles may be determined based on driving preferences of the driver of the vehicle. The control system thus determines the control system of the vehicle, v _{max_1} and v _{min_1} , on the basis of at least one item of information relating to the upcoming road section and possibly additional information, such as information relating to the driver's preferences. The instantaneous speed of the vehicle, ie a speed within an interval between v _{max_1} and v _{min_1} , can be determined in a conventional manner by the speed control function for energy-efficient propulsion of the vehicle. A new set of speed profiles v _{max_transition} and v _{min_transition is} determined between time T2 and time T3. at in 3a In the example shown, the new set of speed profiles v _{max_transition} and v _{min_transition is} determined on the basis of information regarding the occurrence of a change in the conditions that led to the first set of speed profiles v _{max_1} and v _{min_1} and no longer apply. For example, the vehicle may exit the highway and a new speed limit will apply. Thus, the set of speed profiles v _{max_transition} and v _{min_transition} is determined such that a transition is possible between the first set of speed profiles v _{max_1} and v _{min_1} and the second set of speed profiles v _{max_2} and v _{min_2} , which is performed at time T3 and on based on the new speed limit.

Another non-limiting example of controlling the speed of the vehicle 100 in which the invention is implemented is shown in FIG 3b shown.

The initially permitted speed interval of the vehicle 100 in 3b is limited by a first set of speed profiles v _{max_1} and v _{min_1} . Between times T2 and T5, however, the maximum speed is limited by v _max , which is 3b changing continuously over time. The minimum speed v _{min_1} is also limited by v _max between time T3 and time T4. The limiting speed v _max may apply to the vehicle due to given road conditions and a changing vehicle environment, such as characteristics of a road curvature. For example, v _max may be the maximum speed that the vehicle can maintain when navigating a sharp turn. Thus, based on the restricting speed v _max a new permissible speed interval and also a time interval in which the new permissible speed interval is to be used must be determined such that the instantaneous speed of the vehicle is adapted to the given road conditions. The new permitted speed interval is in 3b represented as the interval between a second maximum speed v _{max_2} and a second minimum speed v _{min_2} . The newly allowed speed interval does not necessarily have to be used only in the time interval T2-T5. The time interval in which the new permitted speed interval is to be used, Tx-Ty, the form of the course of the second maximum speed profile v _{max_2} and the second minimum speed profile v _{min_2} , as well as the permitted speed interval are determined according to the exemplary embodiments of the invention in order to achieve the desired driving behavior achieve what is explained in more detail below.

By performing method steps 210-220 of method 200, the allowed speed interval can be adjusted to incorporate complex speed profiles due to various external factors in determining the vehicle 100 speed.

The method 200 and other embodiments of the invention are now discussed in more detail with respect to FIG 4 14 showing a vehicle running on a route at a current speed vact, wherein reference numeral 510 denotes an upcoming road segment. The road on which the vehicle is traveling may be characterized by features and conditions which may affect a permitted speed interval and the instantaneous speed vact of the vehicle 100. The route may, for example, have changing terrain, ie be characterized by a changing road curvature, changing bank angles and changing topography. The conditions along the route with regard to the traffic situation, visibility, etc. can also change.

The speed of the vehicle is controlled by the cruise control function according to method steps 210-220 of method 200.

4 shows a maximum speed profile v _max and a minimum speed profile v _min for vehicle 100, which are determined according to step 210 of method 200 for upcoming road section 510.

As explained above, the maximum speed profile and the minimum speed profile, v _max and v _min , can be determined based on information regarding the road segment in question.

In this exemplary embodiment, the information relating to the upcoming road section can contain information about at least one of the following variables: a speed limit, traffic density, traffic information, a curvature, a bank angle, topography and visibility conditions.

Information about the forthcoming road section can be obtained, for example, from digital maps and from cartographic information in combination with position information, e.g. a global positioning system (GPS). The position information can be used to determine the location of the vehicle in relation to the map data, so that the road section information can be extracted from the map data.

Information regarding the upcoming road segment may be obtained based on information determined in the vehicle 100, in one example. For example, topographical information and information regarding speed limits can be stored in and extracted from the vehicle in combination with position information. Furthermore, contemporary vehicles may have one or more sensors that ver may be used to provide information related to the road segment ahead of the vehicle 100 . For example, vehicle 100 may be equipped with one or more cameras and/or one or more radars that may be used to determine information such as speed limits, traffic density, traffic information, road curvature, bank angles, topography, and visibility.

In another example, information about the upcoming road segment can be obtained based on information from external sources. Such information can be received by communicating with at least one other vehicle or from at least one infrastructure facility via appropriate communication means, such as vehicle-to-vehicle V2V communication, vehicle-to-infrastructure V2I communication, vehicle-to-everything V2X communication, or similar.

The course of the maximum speed profiles and the minimum speed profiles, v _max and v _min , can be influenced by one or more of the above factors, which are 4 are shown. The speed of vehicle 100 may be limited in the upcoming section of road, e.g. by legal speed limits, weather conditions, visibility conditions or the traffic density between position A and position D.

The determination of the maximum speed profile and the minimum speed profile can be performed in the control system of the vehicle 100 using the vehicle characteristics and statistical values related to the driving data. The best reference speed for the vehicle in an interval between the maximum speed profiles and the minimum speed profiles is determined using example-based simulations, optimization algorithms and/or other calculations.

According to the example 4 the maximum speed profile v _max can be derived directly from the given speed restrictions. Once the maximum speed profile v _max is determined, the minimum speed profile v _min can be determined such that the given speed restrictions are met and the performance of the vehicle is optimized.

The maximum speed profile v _max between the points in time T1 and T3 and from the point in time T4 can be determined, for example, on the basis of legal speed restrictions with regard to the corresponding road section. In another example, the maximum speed profile v _max may be determined based on legal speed restrictions, along with other parameters that limit the maximum speed of the vehicle 100, such as weather conditions and/or visibility. For example, the maximum speed profile v _max for a vehicle that is driving on a road with the permitted speed of 120 km/h can be set lower if visibility is limited. In a further exemplary embodiment, the traffic conditions in the area surrounding the vehicle can limit the maximum speed profile v _max . In heavy traffic, the maximum speed profile v _max can be adjusted to the given traffic flow.

A different speed limit for vehicle 100 is set between times T3 and T4. For example, a sharp turn is foreseen, which requires a reduction of the maximum speed profile v _max to avoid the vehicle skidding on the road. Therefore, between time T3 and time T4, corresponding to positions C and D, the maximum speed profile is adjusted in a continuously variable manner such that the vehicle safely negotiates the curve. The maximum speed profile v _max can be calculated here on the basis of, for example, the radius of the anticipated curve and a maximum permissible lateral acceleration.

Similarly, the maximum velocity profile v _min can be determined based on given ratios. In a non-limiting example where the vehicle 100 is traveling on an uphill stretch, the maximum speed profile may be calculated based on potential acceleration of the vehicle on the uphill stretch along with parameters such as vehicle mass, the grade of the road ahead of the vehicle, to name a few to call.

Furthermore, the maximum speed profiles and the minimum speed profiles can be determined based on driving habits of the driver of the vehicle. Thus, the driver of the vehicle can affect vehicle speed by selecting adjustments to the levels of v _min and/or v _max . The driver can, for example, specify his/her driving preferences with regard to energy efficiency, driving comfort and driving time, and thus influence the level and progression of the speed profiles.

In general, the minimum speed profile v _min can be determined on the basis of accelerations and decelerations that are suitable for optimizing the vehicle speed with regard to energy efficiency, driving comfort or travel time. Once v _min and v _max are determined, the vehicle speed can be calculated. The speed of the vehicle at any point in time should not leave the permissible speed interval v _allowed , which is limited by the maximum speed profile and the minimum speed profile. The vehicle speed calculation can be performed with conventional methods by optimizing or simulating various situations to determine an energy efficient reference speed, which is then maintained by the vehicle.

According to one exemplary embodiment, the maximum speed profile and/or the minimum speed profile can also be determined on the basis of a user input into the speed controller.

The driver can be enabled to manually adapt or even set the maximum speed profile and/or the minimum speed profile depending on, for example, the given traffic situation. For example, the driver may feel more comfortable allowing large changes in speed when traffic density is light. In another example, when visibility is poor, the driver may want the vehicle's maximum allowable speed to be reduced.

In one example, user input to the cruise control may be in a conventional manner using, for example, a lever, a push button, a touch-sensitive screen, to name a few. In another example, the cruise control may be controlled by voice commands from the user/driver. With manual input or with voice commands, the driver can select the preferred level with respect to the maximum speed profile and/or the minimum speed profile. On the other hand, the driver can also change a speed profile that has already been defined to another, preferred speed profile.

In one embodiment, the user input in the cruise control may be a driver input mode.

As explained above, an input mode for the driver as a user can relate to one or more predefined execution settings in the vehicle's cruise control.

Non-limiting examples relating to the driver mode can relate to a so-called eco mode, in which the vehicle speed is determined in order to achieve the best possible energy saving; a standard mode may concern an optimization with good fuel economy with good hill performance; and a so-called power mode can affect an optimization of the travel time. The driver is thus given the opportunity to prioritize fuel/energy consumption, travel time, mileage, etc.

By selecting a preferred driver mode, the driver can therefore influence and control the curves of the maximum speed profiles and/or the minimum speed profiles v _max and v _min and accordingly also the size of the permissible speed interval v _allowed .

The allowed speed interval v _allowed provides a framework for the cruise control system in determining the current speed of the vehicle at any instant. At a specific allowed speed interval v _allowed the vehicle's control system finds energy efficient control such that the actual speed is within desired settings.

By establishing a large speed interval, improved fuel economy can be gained because a wider speed range is allowed. The vehicle can use functions such as engine braking, coasting and braking without leaving the allowed speed interval v _allowed .

If the allowed speed interval v _allowed is relatively small, then the behavior of the engine is often abrupt and geared towards maintaining the preferred speed under all conditions.

A determination of the maximum and minimum speed profiles based on user input in a driver mode can be triggered by the driver selecting a preferred driver mode. A driver mode that focuses more on economy gives a wider speed interval v _allowed . In its simplest form, v _allowed consists of a constant minimum speed profile v _min and a constant maximum speed profile v _max . However, if there is a change in a speed limit or a curve, for example, then the speed profiles v _min and v _max cannot be constant. In such situations a selected driver mode influences the speed profiles v _min and v _max in such a way that a driver mode geared more towards economy results in a larger speed interval v _allowed , even if v _min and v _max are not constant.

A central adjustment in automatic speed control is an adjustment of a set speed. The set speed is a preferred speed such that the vehicle maintains the preferred speed and the decision to do so may be automatic or set by the driver. As explained above, the instantaneous speed of the vehicle in the permitted speed interval v _allowed can vary around the set speed in order to obtain a desired driving performance.

In one example, when the vehicle 100 is traveling on a road segment 510, the set speed may assume a constant value, e.g., corresponding to a legal speed limit related to the road segment. The set speed can have a constant value or it can vary over time. The set velocity level over time is referred to herein as the set velocity profile.

In one embodiment, the maximum speed profile v _max and/or the minimum speed profile v _min can be determined such that they continue to be based on a set speed profile for the upcoming road section 510.

Determining the maximum and minimum speed profiles based on a set speed profile for the upcoming road segment 510 can be triggered by a setting of a set speed profile. In one example, the set speed profile can be set manually by the driver. In another example, the set speed profile may be set automatically by a vehicle's cruise control control system, e.g., by reading applicable legal speed limits or in any other conventional manner.

An example is a setting where the set speed is automatically adjusted as a function of the applicable legal speed limit. If the speed limits vary, the set speed will be updated. Another example concerns driving on a winding road, where the set speed must vary according to the risk of slipping or tipping in a curve. Other factors such as poor visibility or weather conditions can also affect the set speed.

As above with reference to 3a is explained, in certain situations speed profiles are required that allow a transition between two sets of speed profiles. the 5a-5c show non-limiting examples for the determination of sets of speed profiles that allow such transitions according to the method of the invention.

In 5a shows a first permitted speed interval v _allowed for the vehicle between times T1 and T2. The first allowed speed interval v _allowed is the interval between a first maximum speed v _{max_1} and a first minimum speed v _{min_1} . At time T2, a second allowed speed interval v _allowed is shown as the interval between a second maximum speed v _{max_2} and a second minimum speed v _{min_2} . A transition between the first set of speeds v _{max_1} and v _{min_1} and the second set of speeds v _{max_2} and v _{min_2} can take place in different ways. As previously explained, the size of the allowed speed interval v _allowed can affect the driving behavior of the vehicle. With a large v _allowed speed interval improved fuel economy can be obtained, while with relatively smaller v _allowed speed intervals the engine response can be more abrupt and optimized for maintaining a preferred speed under all conditions.

5b shows an example of a transition between a first set of speeds v _{max_1} and v _{min_1} and a second set of speeds v _{max_2} and v _{min_2} . The transition has a maximum speed profile v _max and a minimum speed profile v _min between times T2 and T3. The maximum speed profile v _max and the minimum speed profile v _min have the same deceleration start point at time T2, the same deceleration end point at time T3, and the same deceleration rates.

5c shows another example of a transition between a first set of speeds v _{max_1} and v _{min_1} and a second set of speeds v _{max_2} and v _{min_2} . Here a variable permissible speed interval between times T2 and T3 obtained by allowing different deceleration rates for the maximum speed profile v _max and the minimum speed profile v _min . The variation in the deceleration rates of v _max and v _min implies a variation in the start or stop positions with respect to the change in the value of v _min or v _max . The deceleration rate with respect to the maximum speed profile v _max depends on the start and stop position of the speed profile. By shifting, for example, T2 in 5c towards T3 the rate of deceleration increases. By shifting T2 in 5c towards T1, the deceleration rate falls.

How out 5c results, setting appropriate start and/or stop positions of the velocity profiles when a transition between two velocity profiles is required will affect the rate of change, ie the acceleration rate and the deceleration rate, of the velocity profiles and the size of the allowed velocity interval v _allowed . As previously explained, the size of the permitted speed interval v _allowed is relevant for determining the instantaneous speed of the vehicle and at the same time for optimizing the vehicle's preferred driving characteristics (fuel/energy consumption, travel time, etc.).

One skilled in the art will recognize that the same is true when the transition between two sets of velocity profiles affects acceleration rates.

Thus, in one embodiment, the sets of velocity profiles v _max and v _min have different accelerations and/or different decelerations. Furthermore, in one embodiment, the set of velocity profiles v _max and v _min may have different start and/or stop positions for acceleration and/or different start and/or stop positions for deceleration.

As previously explained, the progression of the maximum speed profile v _max and/or the minimum speed profile v _min can differ depending on a number of parameters.

In one embodiment, the maximum velocity profile v _max and/or the minimum velocity profile v _min may include constant velocity intervals.

Constant allowed speed intervals are particularly useful when factors affecting the speed of the vehicle vary in increments. This can apply in particular to a speed limit on the road.

In a further embodiment, the maximum speed profile v _max and/or the minimum speed profile v _min can have continuously varying speed intervals.

Continuously varying speed intervals may be applicable when factors that may affect vehicle speed vary continuously. This can be the case, for example, at a maximum speed that can be maintained in a curve due to the risk of slipping or overturning. Another example is gradual changes in forward visibility due to obstacles on a road.

According to a variant of the invention, a control arrangement 120 for controlling a speed controller of a vehicle 100 is presented. The control arrangement 120 contains a device 121 which is set up to determine a maximum speed profile and a minimum speed profile for an upcoming road section on the basis of information regarding the upcoming road section.

The control arrangement 120 also has a device 122 which is set up to control the speed controller in such a way that a speed of the vehicle 100 in the upcoming road section is controlled in a speed interval between the maximum speed profile and the minimum speed profile.

The control arrangement 120, e.g., a device or a control device, according to the invention can be configured to carry out all that is described above, the subject matter of the patent claims and the exemplary embodiments described here with regard to the method steps. The control arrangement 120 is thus provided with all of the above advantages for the respective embodiment.

The invention also relates to a vehicle 100 that includes the control arrangement 120 .

6 Fig. 12 shows the control arrangement 600/120, which may include or correspond to one or more of the above-mentioned control units 121-122, ie the control units which carry out the method steps according to the invention described here. The control arrangement 600/120 has an arithmetic unit 601 by a suitable processor or microcomputer, eg a circuit for digital signal processing, such as a digital signal processor (DSP), or a circuit with a predetermined specific function, such as an application specific integrated circuit (ASIC). The arithmetic unit 601 is connected to a memory unit 602, which is arranged in the control arrangement 600/120, the memory unit supplying the arithmetic unit 601 with, for example, a stored program code and/or stored data which the arithmetic unit 601 needs to carry out the calculations. The arithmetic unit 601 is also set up to store partial results or final results of calculations in the memory unit 602 .

Furthermore, the control arrangement 600/120 is provided with devices 611, 612, 613, 614 for receiving and transmitting input signals or output signals. These input and output signals can take waveforms, pulses or other forms which can be detected by the means 611, 613 for receiving input signals as information and which can be converted into signals which can be processed by the arithmetic unit 601. These signals are then fed to the arithmetic unit 601 . Devices 612, 614 for the transmission of output signals are set up to convert signals received by computing unit 601 in order to generate output signals in the form of modulated signals, for example, which can be transmitted to other components and/or systems of vehicle 100 .

Each of the connections to the devices for receiving and transmitting input and output signals may be formed by one or more cables, a data bus such as a Controller Area Network (CAN) bus, a Media Orientated Systems Transport (MOST) bus or other bus configuration; be it wired or wireless. A person skilled in the art recognizes that the above computer can be constituted by an arithmetic unit 601 and that the above memory can be constituted by the memory unit 602.

Control systems in contemporary vehicles typically have communication bus systems of one or more communication buses for linking a number of electronic control units (ECU), or controllers, and various components located within the vehicle. Such a control system may have a large number of control units and responsibility for a specific function may be shared among several control units. Vehicles of the type shown here therefore often have significantly more control units than in the 1 and 5 shown, which is well known to a person skilled in the art.

In a shown embodiment, the invention may be implemented by one or more of the above control units 121 and 122. However, the invention may also be implemented, in whole or in part, in one or more other control units already provided in the vehicle 100 , or in control units intended for the invention.

In this document units are often described as arranged to carry out steps of the method according to the invention. This also includes the units being designed and/or configured to carry out these method steps.

The one or more control units 121 and 122 are in 1 shown as separate entities. However, these units can also be logically separate and physically installed together in the same unit, or they can both be logically and physically installed together in one unit. These units can each correspond, for example, to groups of instructions which are in the form of a program code which is entered into a processor/the arithmetic unit 601 and used there when the units are respectively active and/or used for the execution of method steps.

The person skilled in the art recognizes that exemplary embodiments described here can also be implemented in a computer program which, when executed in a computer, instructs it to carry out the corresponding method. The computer program is usually provided by a computer program product 603, which is stored in a non-volatile digital storage medium, the computer program being contained in the computer-readable medium of the computer program product. The computer-readable medium can be any suitable storage medium, such as read only memory (ROM), programmable read only memory (PROM), erasable programmable read only memory (EPROM), flash memory, electronically erasable programmable read only memory (EEPROM), hard disk drive, Etc.

The invention is not limited to the embodiments described above. On the contrary, the invention relates to and encompasses all possible ones Embodiments falling within the scope of the independent claims.

Claims (16)

A method (200) for controlling a cruise control of a vehicle (100), the method (200) comprising: determining a maximum speed profile (v _max ) and a minimum speed profile (v _min ) for an upcoming road section (510) based on information about the upcoming road segment road segment (510); and controlling the speed controller (510) such that a speed of the vehicle (100) in the upcoming road section (510) lies in a speed interval between the maximum speed profile and the minimum speed profile. Method (200) according to claim 1 , the method (200) comprising: determining the maximum speed profile (v _max ) further based on a user input in the speed controller. Method (200) according to any one of Claims 1 or 2 , the method (200) comprising: determining the minimum speed profile (v _min ) further based on the user input in the speed controller. Method (200) according to any one of claims 2 or 3 , wherein the user input in the cruise control is an input related to a driver mode. Method (200) according to one of the preceding claims, wherein the method (200) comprises: determining the maximum speed profile (v _max ) further on the basis of a set speed profile for the upcoming road section (510). Method (200) according to one of the preceding claims, wherein the method (200) comprises: determining the minimum speed profile (v _min ) further on the basis of a set speed profile for the upcoming road section (510). Method (200) according to one of the preceding claims, wherein the maximum speed profile (v _max ) and the minimum speed profile (v _min ) have different accelerations and/or different decelerations. Method (200) according to one of the preceding claims, wherein the maximum speed profile (v _max ) and the minimum speed profile (v _min ) have different starting positions with regard to the acceleration and/or with regard to the decelerations. Method (200) according to one of the preceding claims, wherein the maximum speed profile (v _max ) and the minimum speed profile (v _min ) have different stop positions with regard to the acceleration and/or with regard to the decelerations. Method (200) according to one of the preceding claims, wherein the maximum speed profile (v _max ) and/or the minimum speed profile (v _min ) have constant speed intervals. Method (200) according to one of the preceding claims, wherein the maximum speed profile (v _max ) and/or the minimum speed profile (v _min ) have continuously changing speed intervals. Method (200) according to one of the preceding claims, wherein the information about the upcoming road section (510) contains information about at least one of the following variables: a speed limit, a traffic density, traffic information, a curvature, a bank angle, a topography and visibility conditions. Control arrangement (120) for controlling a speed controller of a vehicle (100), the control arrangement (120) being set up for: determining a maximum speed profile (v _max ) and a minimum speed profile (v _min ) for an upcoming road section (510) on the basis of information about the upcoming road segment (510); and for controlling the speed controller such that a speed of the vehicle (100) in the upcoming road segment (510) lies in a speed interval between the maximum speed profile and the minimum speed profile. Vehicle (100) with a control arrangement (120) according to Claim 13 . Computer program with instructions which, when the program is executed by a computer, cause the computer to use a method (200) according to one of Claims 1 until 12 to execute. A computer-readable medium containing instructions which, when executed by a computer, cause the computer to perform the method (200) according to any one of Claims 1 until 12 to execute.

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