DE102014204983A1 - Control device and method for determining the position of a vehicle - Google Patents

Abstract

The present invention relates to a control unit (1), in particular for a vehicle (10), wherein the control unit (1) can be connected to position-determining sensors (2) of the vehicle (10), the control unit (1) being provided with environmental sensors (3). the vehicle (10) is connectable, and wherein the control device (1) is arranged to move the vehicle (10) along a predefined trajectory (5), characterized in that the control device (1) is set up on the basis of the position determination sensors (2 ) to determine a current position of the vehicle (10) on the predefined trajectory (5), and at predefined locations (6) of the trajectory (5) by comparing a current environment (4) of the vehicle detected using the environmental sensors (3) (10) to correct the position with an environment stored for the trajectory (5).

Description

State of the art

The present invention relates to a control device for a vehicle and to a method for operating a vehicle. Finally, the invention relates to a vehicle that is equipped with said control unit and / or that can perform the aforementioned method.

Driver assistance systems are known from the prior art, which allow the driver to automate recurring maneuvers, such as driving into a private garage. This is ensured by the fact that the driver performs the maneuver once and while the system records the trajectory traversed. Subsequently, the recorded driving maneuver can be retrieved, wherein the vehicle is fully automatically or semi-automatically controlled by the system. Such an assistance system is in particular from the DE 10 331 948 A1 known.

As a prerequisite for retrieving the stored driving maneuver the correct recognition of the starting position as well as the derivation of the correct relation between position and orientation of the vehicle in the recording of the maneuver and in the retrieval of the maneuver are necessary. Furthermore, it is essential for the implementation of the aforementioned automated shutdown that the vehicle always follows the learned trajectory. Thus, a constant adjustment of a current environment, which can be detected for example by means of sensors, and a stored environment is necessary. Since a variety of environmental data must be stored in this way, a high memory requirement is needed. The memory requirement grows with the length of the trajectory, so that especially in the storage of multiple maneuvers the required storage space for applications in vehicles is too large.

Disclosure of the invention

With the control device according to the invention, a reduction of the memory requirement is possible. For this purpose, the control unit according to the invention, which is designed in particular for a vehicle, includes interfaces with which the control unit can be connected to position-determining sensors of the vehicle and to environmental sensors of the vehicle. According to the invention, the control device is set up to move the vehicle along a predefined trajectory, wherein a current position of the vehicle on the predefined trajectory is determined on the basis of position determination sensors. Since a position determination is often associated with an error, a recurrent error correction is necessary. For this purpose, the control device is set up to compare, at predefined locations of the trajectory, a current environment of the vehicle recorded by means of the environmental sensors with an environment of the vehicle stored for the trajectory. Based on this comparison, a correction of the position is vornehmbar. Thus, the controller is configured to correct the particular position of the vehicle by comparison with a current environment of the vehicle. Thus, on the one hand, a very simple position determination is available, while still ensuring high accuracy.

The invention also relates to a method for operating a vehicle. For this purpose, the vehicle is guided along a trajectory, wherein always a current position of the vehicle is determined on the trajectory. In particular, it is provided that steering angle signal data and / or wheel rotation data are used. At the same time the environment of the vehicle is detected by environmental sensors. The environment sensors are in particular distance-measuring sensors, particularly preferably ultrasonic sensors. Alternatively, the environmental sensors are preferably imaging sensors, in particular video cameras. As soon as the vehicle is at predefined locations of the trajectory, a comparison of the detected environment with a stored environment takes place. Subsequently, the specific position on the trajectory is corrected, in particular the results from the comparison of the detected environment and the stored environment are used. Therefore, there is always a current and accurate position on the trajectory available, with only very simple measurements must be performed. In particular, it is not necessary to detect the environment over the entire trajectory.

The dependent claims have preferred developments of the invention to the content.

The predefined locations are preferably those locations at which a large error in the position determination by means of odometry is to be expected. These places are especially in curves. Alternatively or additionally, it is preferably provided that the predefined locations correspond to those locations at which an estimated error exceeds a predefined threshold value. The error is preferably determined by means of an error model. For the estimation of errors of the position determination by means of odometry, it is considered in particular that high errors occur in curves with strong yaw angle changes.

Therefore, it is particularly preferred that the error model the error based on a distance already traveled and / or on a yaw angle change and / or determined on a speed of the vehicle.

The position determination sensors are preferably odometry sensors. Thus, the position determination is preferably carried out by means odometry. In particular, it is provided that steering angle signal data and / or wheel rotation data are used. Alternatively or additionally, it is provided that the position-determining sensors are advantageously sensors for dead-reckoning. Thus, the sensors include in particular a time sensor and a speed sensor. Particularly preferably, the sensors additionally comprise a direction sensor.

In a preferred embodiment of the invention, the stored environment is detected by an initial trajectory traversing. Thus, a user of the vehicle is allowed to record a recurring route once for the vehicle to learn this way. Subsequently, the control unit can lead the vehicle along this route, with all travel movements preferably being carried out autonomously.

Finally, it is advantageously provided that environmental data are stored exclusively for an environment at the predefined locations of the trajectory. Thus, in particular, it is not necessary to store environmental data at a plurality of locations of the trajectory or continuously along the trajectory. Therefore, a reduction of the necessary memory requirements is possible. This means that hardware requirements of the controller are kept very low.

In particular, the method according to the invention is carried out in such a way that the environment is detected by initially traversing the trajectory, in which environmental sensors continuously scan the environment. In this case, environmental data are preferably stored temporarily and checked after reaching a target position on the trajectory. Finally, environmental data are permanently stored only in those places where a large error in the position determination is to be expected. Thus, only a small permanent memory requirement is needed for the inventive method. Most places where a big error in positioning is expected are mostly curves. Since curves usually can not be predicted during the initial trajectory departure, environmental data are preferably also stored permanently before the curve in order to enable a later comparison of the detected environment with the stored environment before the curve and thus even before the possible increase in the position determination error.

Particularly preferably, it is provided that the environment is detected by initially traversing the trajectory by environment sensors continuously scanning the environment. In this case, environmental data are stored only in places where a large error in the position determination is to be expected. The presence of such sites is analogous to the review described above. The particularly preferred embodiment has the advantage that the memory to be temporarily provided is further reduced, since the complete environment is not first to be stored.

The position determination is preferably carried out by means of intertial navigation. Alternatively or additionally, it is provided in particular that the position of the vehicle is determined by means of odometry. Alternatively or additionally, it is preferably provided that the position of the vehicle is determined by means of dead reckoning.

Finally, the invention relates to a vehicle, wherein the vehicle comprises a control device, as described above. Alternatively or additionally, the vehicle is set up to carry out a method as described above.

Brief description of the drawings

Hereinafter, embodiments of the invention will be described in detail with reference to the accompanying drawings. In the drawing is:

1 a schematic overview of a trajectory in an environment, wherein a control device is arranged according to an embodiment of the invention, a vehicle along this trajectory, and

2 a schematic illustration of a vehicle according to an embodiment of the invention, wherein the vehicle comprises the control unit according to the embodiment of the invention.

1 shows a trajectory 5 starting from a starting point 9 to a destination point 7 through an environment 4 runs. Within the environment 4 is a variety of obstacles 8th available. It is intended that a vehicle 10 along the trajectory 5 is guided, the vehicle 10 an autonomous driving movement from the starting point 9 to the destination point 7 should perform. This is the trajectory 5 initially aborted, the vehicle 10 the environment 4 recorded and the course of the trajectory 5 stores.

The vehicle 10 is in 2 shown. To capture the environment 4 points the vehicle 10 environmental sensors 3 on that with a control unit 1 are connected. Furthermore, the control unit 1 with position sensors 2 of the vehicle 10 connected. The positioning sensors 2 are especially odometry sensors. In this way, both a position of the vehicle 10 on the trajectory 5 detectable while with the environment sensors 3 at the same time the environment 4 is detected.

In the in 1 shown trajectory 5 There are two changes of direction by 90 °. These changes of direction lead to errors of determination when a position of the vehicle 10 on the trajectory 5 by means of the position-determining sensors 2 is determined. Therefore, the controller 1 established an error in the position determination by means of the position-determining sensors 2 to estimate an accuracy of the current position. The error is preferred depending on a distance traveled by the vehicle 10 on the trajectory 5 and / or a yaw angle change or an absolute amount of the yaw angle change and / or the speed of the vehicle 10 certainly. All the above-mentioned values are in this case by means of a plurality of position determination sensors designed as odometry sensors 2 at the wheels of the vehicle 10 determined. Once the error exceeds a predefined threshold, it is preferably provided that the control unit 1 by means of environment sensors 3 the environment 4 detected. The environment sensors 3 are advantageously distance-measuring sensors, such as in particular radar sensors or ultrasonic sensors or are preferably imaging sensors, in particular cameras. Thus, the environment sensors determine 3 Distance data and / or 3D point clouds and / or object data, preferably with dimensions, and / or image features, in particular road markings or traffic signs. The control unit 1 is further set up this data with a stored image of the environment 4 compare the stored image at the initial retraction of the trajectory 5 has been recorded. By comparing the measured data with the stored data is thus a correction of the position of the vehicle 10 on the trajectory 5 allows.

It is particularly preferred that an image of the environment is provided 4 only at predefined places 6 is stored. The predefined places 6 are advantageously in the range of changes in direction of the trajectory 5 , so that only environmental information is stored at those points at which the error in the position determination by means of the positioning sensors designed as odometry sensors 2 expected to be very high. Because only at the predefined places 6 an adjustment of the detected environment 4 with the stored environment is necessary, so from the control unit 1 Storage requirement to be provided considerably reduced, since not for the entire trajectory 5 Environmental information is to be saved.

Overall, the controller allows 1 and the vehicle according to the invention 10 an autonomous guidance along the trajectory 5 , This is particularly advantageous when the vehicle 10 independently to a predefined area, in particular a parking lot or a garage to be moved. In this case, the control unit according to the invention, the vehicle allows 10 easy and safe along the trajectory 5 without hitting obstacles 8th respectively.

In addition to the written disclosure is expressly attached to the disclosure of 1 and 2 Referenced.

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 10331948 A1 [0002]

Claims (12)

Control unit ( 1 ), in particular for a vehicle ( 10 ), - whereby the control unit ( 1 ) with position sensors ( 2 ) of the vehicle ( 10 ) is connectable, - wherein the control unit ( 1 ) with environmental sensors ( 3 ) of the vehicle ( 10 ), and - wherein the control unit ( 1 ), the vehicle ( 10 ) along a predefined trajectory ( 5 ), characterized in that the control unit ( 1 ), - based on the position-determining sensors ( 2 ) a current position of the vehicle ( 10 ) on the predefined trajectory ( 5 ), and - at predefined places ( 6 ) of the trajectory ( 5 ) by comparing one with the environment sensors ( 3 ) captured current environment ( 4 ) of the vehicle ( 10 ) with one for the trajectory ( 5 ) stored environment to correct the position. Control unit ( 1 ) according to claim 1, characterized in that the predefined locations ( 6 ) are those places where a large error in positioning is expected. Control unit ( 1 ) according to claim 2, characterized in that the predefined locations ( 6 ) correspond to those locations at which an error estimated by means of an error model exceeds a predefined threshold value. Control unit ( 1 ) according to claim 3, characterized in that the estimated error, based on an already traveled distance on the trajectory and / or on a yaw angle change and / or on a speed of the vehicle, can be determined by the error model. Control unit ( 1 ) according to one of the preceding claims, characterized in that the position-determining sensors ( 2 ) Odometricsensoren and / or sensors for dead reckoning include. Control unit ( 1 ) according to any one of the preceding claims, characterized in that the stored environment by an initial trajectory traversing ( 5 ) is detected. Control unit according to one of the preceding claims, characterized in that environmental data exclusively for an environment at the predefined locations ( 6 ) of the trajectors ( 5 ) is stored. Method for operating a vehicle ( 1 ), comprising the steps - guiding the vehicle ( 10 ) along a trajectory ( 5 ), - determining a current position of the vehicle ( 10 ) on the trajectory ( 5 ), - capturing an environment ( 4 ) of the vehicle ( 10 ) by means of environment sensors ( 3 ), - Comparison of the detected environment with a stored environment at predefined locations ( 6 ) of the trajectories ( 5 ), and - Correcting the specific position on the trajectory ( 5 ). Method according to claim 8, characterized in that the environment ( 4 ) by initially traversing the trajectory ( 5 ) by means of environment sensors ( 3 ), whereby environment data is temporarily stored and after reaching a target position ( 7 ) on the trajectory ( 5 ) the environmental data is checked and stored permanently only in those places where a large error in the position determination is to be expected. Method according to claim 8, characterized in that the environment ( 4 ) by initially traversing the trajectory ( 5 ) by means of environment sensors ( 3 ) is detected, wherein environmental data are stored only in those places where a large error in the position determination is to be expected. Method according to one of claims 8 to 10, characterized in that determining the current position of the vehicle ( 10 ) on the trajectory ( 5 ) is carried out by means of odometry and / or via dead reckoning. Vehicle ( 10 ), comprising a control unit ( 1 ) according to any one of claims 1 to 7 and / or adapted to carry out a method according to any one of claims 8 to 11.

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