DE102009041586A1 - Method for increasing accuracy of sensor-detected position data of e.g. truck, involves assigning toll station position with higher accuracy than vehicles position, and correcting vehicles position on basis of exact position of toll station - Google Patents

Abstract

The method involves determining a position of vehicles (10, 10', 10'') using global positioning system-sensors (14, 14', 14''). A position of a toll station (12) is transferred from the toll station to the vehicles at a time point, at which the vehicles pass the toll station. The position of the toll station is assigned with a higher accuracy than the position of the vehicles. The position of the vehicles is corrected on basis of the transferred exact position of the toll station. A distance of the vehicles to the toll station is smaller than a predetermined threshold value at the time point. An independent claim is also included for a method for detecting sudden, temporary trouble or change of traffic route.

Description

The invention relates to a method for increasing the accuracy of sensor-detected position data. The invention further relates to the use of these corrected position data for in particular automated creation and / or correction of a digital road map.

Mapping projects typically use a GPS or general GNSS self-positioning system. This applies to both commercial providers and community projects such as: Eg OpenStreetMap. The problem here is the inaccuracy of the positioning signal whose accuracy is time-dependent due to the available satellite constellation and dependent on the environment, for example due to urban canyons, tunnels, etc. Therefore, z. B. the road information (coordinates) in such a created map software with errors. The measurements are usually carried out by individual measurements. To increase the accuracy of a multiple measurement can be made, either multiple vehicles are used or a multiple departure of the route is provided at different times. The statistical averaging of the acquired values is also an imprecise approach since it can not correct, for example, an environment-dependent inaccuracy.

Out DE 698 23 462 A method for updating and improving a geographic database using feedback is known. Feedback in this context means that a plurality of vehicles having sensors collect physical characteristics of a geographical area and transmit them to the database. Trust levels can be assigned to the data items in this database. The confidence level is a quantity that indicates the certainty with which the data unit in the central geographic database matches the actual physical feature in the geographic area. The confidence level of a data item may be increased or decreased according to the frequency and freshness with which the feature is detected by the data collection vehicles. Here, however, only a temporal correction takes place, since only the question is considered whether a stored geographic feature is probably still current or not. By the method described here, an increase in the accuracy of sensor-detected position data is not possible.

The object of the invention is to provide a method with which the accuracy of sensor-detected position data can be increased. It is another object of the invention to provide a way by which the accuracy of automated created or corrected digital road maps can be increased.

The object is achieved according to the invention by the features of method claim 1 and by the features of claim 13.

The method according to the invention for increasing the accuracy of sensor-detected position data comprises the following steps:
By means of a sensor, the position of a first moving object is determined. This object may be, for example, a vehicle, for. B. act a truck. The position of a second object is transmitted from this second object to the first moving object. This happens at the moment when the first moving object, the second object happens. The second object is an object whose position can be determined with higher accuracy than the position of the first moving object. Preferably, the second object is immovable and may be, for example, a toll station, a road junction, a building or the like. It is essential here that the position of the second object has been determined with high accuracy and is known. According to the invention, the sensor-determined position of the first movable object is corrected on the basis of the transmitted, more accurate position of the second object.

By using the more precise position data of the second object for correcting the sensor-determined position of the first object, this position can thus be determined more accurately first. Further, future or temporally past positions of the first moving object may be corrected based on the transmitted more accurate position of the second object. In this case, the terms future or temporal are to be understood in relation to the point in time at which the first moving object passes the second object.

This time is preferably set as the time at which the distance of the first movable object to the second object is smaller than a predetermined threshold.

Preferably, correcting the position of the first movable object determined by the sensor includes calculating an error in that sensor-determined position based on the difference of that position to the determined more accurate position of the second object.

Furthermore, it is possible to determine the positions, determined by means of sensors, of further moving objects, for example other vehicles, which in a defined time window at the point in time at which the first moving object is the second object also happens to correct the second object based on the calculated error in the sensor-averaged position of the first moving object. In particular, the correction of the sensor-determined positions of the further actuated objects also includes the correction of future and temporally past positions of these objects.

It is preferred that the further moving objects not the position of the second object, but only the calculated error of the sensor-determined position of the first movable object at the time at which the first moving object passes the second object is transmitted.

The transmission of the position of the second object is preferably carried out by means of a data transmission with a short range. In particular, this may be an infrared transmission or the use of a short range radio technology, for example DSRC.

The position of the first moving object can be determined, for example, by means of GNSS. Furthermore, the following methods for determining the position of the first moving object can be used: Visual positioning by video data by objects such. B. Houses are recognized on the image and then the position is determined; Induction loops; Tags in the roadway; Localization by means of cell-based radio networks, for example GSM triangulation; Localization by means of W-LAN, in which case it is possible to use infrastructure units which are used at the roadside for vehicle-to-infrastructure communication; Chips embedded in the roadway; Localization using a map, a wheel speed sensor and a compass. In the last option, the number of possible positions on the map is gradually reduced, so that with sufficient accuracy of the compass and the wheel speed sensors often one to two kilometers are sufficient for the initial localization.

The first moving object may be, for example, a car, truck or motorcycle, and it must have the necessary transmission technology to receive the position of the second object by means of a data transmission.

In an alternative embodiment, the second object may also be a moving object, its position being determined by means of additional and / or more accurate sensors than the position of the first moving object, so that the position of the second moving object is more accurate.

The invention further relates to the use of the position data of one or more moving objects described using the method described so far for the particularly automated creation and / or correction of a digital road map. This makes it possible to increase the accuracy of the created digital road maps with little effort. In particular, it is no longer necessary for multiple measurements to be made, for example, by a vehicle driving off a certain distance several times or several vehicles being used for map generation. Furthermore, it is also possible to correct environment-dependent inaccuracies, which can be caused, for example, in a GPS measurement by street canyons, tunnels, etc., since the inventive correction of the sensor-detected position data also works in environments in which no or only a poor GPS Signal is available.

An independent invention relates to a method for detecting sudden and / or temporary disturbances and / or changes on traffic routes.

The creation of large databases z. As with geographic data, such as those used for navigation applications, is complex and costly. The necessary updates of the data material regularly take up large resources, for example when new or changed roads have to be included in the case of map data. The updated map data must be made available to the users after the update. This can be done for example by update CD's. With respect to map data, larger providers use approaches such as user map sharing (through a peer-to-peer system) or online updates. However, this solves only the distribution problem and not the data acquisition problem.

Furthermore, no possibility is known from the prior art to detect short-term occurring and / or temporary disturbances on traffic routes and to take into account during navigation.

The object of the invention is to provide a simple method for detecting sudden and / or temporary disturbances and / or changes on traffic routes.

The object is achieved by the features of the method claim 14 and by the features of the use claim 16th

In the method according to the invention, demand-independent acquisition of data containing information about properties of traffic routes is carried out by a plurality of sensors in several vehicles. Demand unbound in this context means that data are collected without these specific application goals of the respective sensors or their primary application purpose. This can be done, for example, in a phase of underutilization or non-use of the sensors. The data acquired independently of the demand by the sensors may be, for example, camera images, position, speed, distances to the crash barriers or buildings, etc. Further, for example, data may be used by acceleration sensors and other sensors.

According to the invention, the acquired data is transmitted to a central evaluation unit. This can be done either immediately after detection or after a caching, for example, depending on the data communication costs, the total energy balance or the utilization of the sensor or target network. In the evaluation unit, the transmitted data of the individual sensors are fused together and / or combined with one another so that it is possible to draw conclusions about the presence of sudden and / or temporary disturbances and / or changes on the traffic routes by evaluating the entirety of the data. In other words, the data transmitted after its transmission are processed according to the nature of the data and its suitability and combined and fused with other data sets from the same or a different sensor network value. As a mobile sensor network, for example, a vehicle can be viewed. Only through the combination of the data in the evaluation unit, the meaning of the data arises or only there, the individual data can be improved by suitable methods. For example, by a temporal backward and forward improvement of the demand-independent data acquired their information content can be significantly increased. The information content of an information, for example that spinning wheels were detected on a vehicle and thus possibly the road is icy, can be increased by adding further data. For example, a local temperature sensor installed in the vehicle can be consulted to check the temperature at the corresponding position of the vehicle. Furthermore, accurate weather information from weather stations in the evaluation unit can be considered. Thus, both local additional information can be used as well as those that are determined by the evaluation or made available.

On-demand data collection does not affect the functionality of the primary systems that use this data. The provision and transmission of the data to the evaluation unit by a multiplicity of systems or vehicles generates considerable added value.

According to the invention, such sensors are used which serve the primary purpose of vehicle control or are used in built-in safety systems. In addition to the sensors already mentioned, they may be, for example, the following sensors: longitudinal and lateral acceleration sensors for ABS, ASR, accident detection, RADAR, LIDAR, laser or ultrasound sensors, which enable distance and object recognition in the vehicle environment. Furthermore, existing GNSS sensors, such as. B. GPS can be used. In addition, the use of data from rear view cameras is possible. Existing communication systems such as 2G and 3G cellular or W-LAN, DSRC, as well as vehicle-to-X communication are suitable for transmitting the collected data.

The data collected by the sensors in different vehicles can be transmitted in anonymous form to the evaluation unit. This can also be done with a time lag from their detection, for example, via a free own W-LAN Excess point at home or at a gas station or other public facilities, a low data rate at night with UMTS, etc. For the time-delayed transmission is a storage of recorded data possible. Transmission via vehicle-to-X communication to a corresponding infrastructure element is also free of charge.

In one exemplary application, on a driving route, the data from acceleration sensors could be detected, which indicate that there are particularly many potholes on the route. These data acquired independently of demand have only limited value as individual information, since in this example the chassis of a single vehicle could also be defective. These individual information is collected according to the invention in the evaluation and preferably with further information z. B. Date and time combined. If the system now repeatedly receives the information about a poor condition of a road through a combination of several needs-independently detected sensor values, for example, either the map material can be completed automatically with this information or this information is transmitted to vehicles that could use them. Further conclusions that could be drawn from the collected sensor data, z. B. that a lane is closed on a highway, a road is closed or a one-way street or the like.

Were based on the method just described by means of sensor data, for example Information about the condition of a travel route collected at a certain position, the accuracy of the position can be improved by the first method described in the present patent application, for example by means of a forward and Rückwärtsannotation.

In a particularly preferred embodiment, a sudden change of the sensor signals registered by a plurality of sensors in different vehicles at the same position is used as an indicator of a fault occurring at that position of the traffic route. This may be, for example, lightning ice, a pothole by frost, smoothness caused by an oil spill, and so on. Thus, not only long-term changes in traffic routes are detected according to the invention, but also short-term, suddenly occurring changes or disturbances.

These detected sudden and / or temporary disruptions or changes to traffic routes may be used to adapt navigation information or instructions. In particular, this makes it possible to adapt the prediction of the probable travel time by a navigation system. If, for example, a single-lane traffic management of a motorway section becomes known through a combination of sensor information, the navigation system can reduce the expected future average speed on this motorway section based on this information and thus adapt the expected arrival time accordingly.

In the following, a preferred embodiment of the invention will be explained with reference to a figure.

The figure shows a schematic view of a system by means of which the method according to the invention will be explained.

In the figure are three vehicles 10 . 10 ' and 10 '' shown. Each of these vehicles has a GPS sensor 14 . 14 ' . 14 '' through in conjunction with the satellite 16 a GPS determination of the position of the vehicles 10 . 10 ' . 10 '' is possible. At the second object 12 it is a toll station or other object whose exact position is known with higher accuracy, which is traversed by the vehicles at different times.

When driving through the tollbooth 12 through the first vehicle 10 becomes the position of the toll station 12 , which is known with a very high accuracy, to the first vehicle 10 , transmitted for example by infrared. The GPS position of the first vehicle 10 using the GPS sensor 14 is determined based on the transmitted position of the toll station 12 corrected. This occurs at the time when the first vehicle 10 directly at or below the tollbooth 12 located, ie the tollbooth 12 happens. In the figure, the threshold value s is shown schematically, which should make it clear that the time at which the first vehicle 10 the tollbooth 12 happens when the time is set at which the distance a of the first vehicle 10 to the toll booth 12 is less than a predetermined threshold s. Of course, the size of this distance s in practice is less than shown in the figure.

Correcting by means of the sensor 14 certain position of the first vehicle 10 concludes calculating an error in this sensor-averaged position based on the difference of that position to the transmitted more accurate position of the toll 12 one.

It is not just a correction of the position of the first vehicle 10 at the time of this vehicle the toll booth 12 happens. Rather, there is also a correction of future or temporally past positions of the first vehicle 10 based on the transmitted position of the toll station 12 ,

Furthermore, a correction is carried out by means of sensors 14 ' . 14 '' Determined positions of other vehicles 10 ' . 10 '' in a defined time window at the time the first vehicle enters the tollbooth 12 happens to also pass through the toll station based on the calculated error in the sensor-averaged position of the first vehicle. Here too, the correction of the sensor-determined positions of the other vehicles 10 ' . 10 '' include the correction of future and past positions. Preference is given to the other vehicles 10 ' . 10 '' not the position of the tollbooth 12 itself, but only the calculated error of the sensor-determined position of the first vehicle 10 at the time when the first vehicle 10 the toll station 12 happens, transmitted.

The second object, whose position is known with a higher accuracy, does not necessarily have to actively signal the vehicle to pass through. For example, driving through could also be done by the vehicle sensor system z. B. be detected with a camera. The second object may, for example, also be a beacon embedded in the roadway, such as an RFID chip, which is detected when driving over.

By the method according to the invention, in addition to the sensor-detected position data, further sensor-recorded data can also be improved in terms of accuracy.

The thus corrected position data of one or more vehicles 10 . 10 ' . 10 '' can be used to automatically create and / or correct a digital road map.

QUOTES INCLUDE IN THE DESCRIPTION

This list of the documents listed by the applicant has been generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Cited patent literature

• DE 69823462 [0003]

Claims (16)

Method for increasing the accuracy of sensor-detected position data, comprising the steps of: - determining the position of a first mobile object ( 10 ) by means of a sensor ( 14 ); Transmitting the position of a second object ( 12 ) of this second object ( 12 ) to the first moving object ( 10 ) at the time when the first moving object ( 10 ) the second object ( 12 ), the position of the second object ( 12 ) is determinable with a higher accuracy than the position of the first moving object ( 10 ); - Correct the by means of the sensor ( 14 ) determined position of the first movable object ( 10 ) based on the transmitted more precise position of the second object ( 12 ). Method according to claim 1, wherein the time at which the first moving object ( 10 ) the second object ( 12 ) happens, as the time is determined at which the distance (a) of the first moving object ( 10 ) to the second object ( 12 ) is less than a predetermined threshold (s). Method according to claim 1 or 2, wherein the second object ( 12 ) is immovable, so that the more accurate position of this object is a fixed position. Method according to one of claims 1 to 3, wherein the correction by means of the sensor ( 14 ) determined position of the first movable object ( 10 ) calculating an error in this sensor-determined position based on the difference of this position to the transmitted, more accurate position of the second object ( 12 ). Method according to one of claims 1 to 4, characterized by the additional step of: - correcting in relation to the time at which the first moving object ( 10 ) the second object ( 12 ) happens, future or past positions of the first moving object ( 10 ) based on the transmitted more precise position of the second object ( 12 ). Method according to claim 4, characterized by the additional step of: - correcting by means of sensors ( 14 ' . 14 '' ) determined positions of other moving objects ( 10 ' . 10 '' ) in a defined time window at the time at which the first moving object ( 10 ) the second object ( 12 ) happens, also the second object ( 12 ) based on the calculated error in the sensor-averaged position of the first moving object, wherein the correction of the sensor-determined positions of the further moving objects ( 10 ' . 10 '' ) includes, in particular, the correction of future and past positions. Method according to claim 6, wherein the further movable objects ( 10 ' . 10 '' ) not the position of the second object ( 12 ), but only the calculated error of the sensor-determined position of the first moving object ( 10 ) at the time when the first moving object ( 10 ) the second object ( 12 ) happens, is transmitted. Method according to one of claims 1 to 7, wherein the position of the second object ( 12 ) by means of a data transmission with short range, in particular via infrared or a short range radio technology to the first moving object ( 10 ) is transmitted. Method according to one of claims 1 to 8, wherein the position of the first movable object ( 10 ) is determined by GNSS. Method according to one of claims 1 to 9, wherein the first moving object ( 10 ) is a vehicle, in particular a car, truck or motorcycle. Method according to one of claims 1 to 10, wherein the second object ( 12 ) is a toll station. Method according to one of claims 1 to 11, wherein the second object is also a moving object and its position is determined by means of additional and / or more accurate sensors than the position of the first moving object ( 10 ), so that the position of the second moving object is more accurate. Use of the position data of one or more moving objects corrected using the method according to one of claims 1 to 12 10 . 10 ' . 10 '' for in particular automated creation and / or correction of a digital road map. Method for detecting sudden and / or temporary disturbances and / or changes in traffic routes, with the steps: Capturing data containing information about characteristics of traffic lanes by multiple sensors in several vehicles, as required Transmitting the collected data from the vehicles to a central evaluation unit, - Fusing and / or combining the determined data of the individual sensors together in the evaluation, so that by an evaluation of the totality of the data conclusions on the presence of sudden and / or temporary disturbances on the roads can be obtained. The method of claim 14, wherein a sudden change of the sensor signals generated by a plurality of sensors in different vehicles is registered at the same position, is used as an indicator of a fault occurred at this position of the traffic route. Use of the sudden and / or temporary disturbances on traffic routes detected by a method according to one of claims 14 or 15 for adaptation of navigation information or instructions, in particular for adaptation of the prediction of the anticipated travel time by a navigation system.

Images