阅读说明：本技术 用于初始校准车辆的驾驶员辅助系统的传感器的方法 (Method for initially calibrating a sensor of a driver assistance system of a vehicle ) 是由 A·C·乌尔里希 S·多伦坎普 于 2019-06-21 设计创作，主要内容包括：一种用于对车辆(10)的驾驶员辅助系统的传感器(1)进行初始校准的方法,所述方法具有以下步骤：借助布置在所述车辆外部的参考装置(2)检测所述车辆(10)的轨迹；求取所述传感器(1)的传感器轴线(5)；由所检测的轨迹求取所述车辆(10)的行驶轴线(6)；求取所述传感器轴线(5)与所述行驶轴线(6)之间的角度(α)。(A method for initial calibration of a sensor (1) of a driver assistance system of a vehicle (10), the method having the steps of: -detecting the trajectory of the vehicle (10) by means of a reference device (2) arranged outside the vehicle; determining a sensor axis (5) of the sensor (1); determining a driving axis (6) of the vehicle (10) from the detected trajectory; an angle (alpha) between the sensor axis (5) and the driving axis (6) is determined.)

1. A method for initial calibration of a sensor (1) of a driver assistance system of a vehicle (10), the method having the steps of:

-detecting the trajectory of the vehicle (10) by means of a reference device (2) arranged outside the vehicle;

determining a sensor axis (5) of the sensor (1);

determining a driving axis (6) of the vehicle (10) from the detected trajectory;

an angle (alpha) between the sensor axis (5) and the driving axis (6) is determined.

2. The method according to claim 1, wherein the trajectory is detected by means of a position (P1 … Pn) of the vehicle (10).

3. Method according to claim 1 or 2, wherein the finding of the sensor axis (5) is performed by means of a point target device (3) and a control device (4) of the sensor (1), the point target device being known in position and being arranged outside the vehicle (10).

4. Method according to any one of claims 1 to 3, wherein the data of the travel axis (6) are transmitted wirelessly from the reference device (2) to a control device (4) of the sensor (1).

5. The method of claim 4, wherein the wireless transmission of the data is performed over a WLAN.

6. Method according to any one of claims 3 to 5, wherein the angle (a) is determined by means of the control device (4).

7. The method according to any of the preceding claims, wherein the method is performed for at least one of a video sensor, a radar sensor, a lidar sensor.

8. A system (200) for initial calibration of a sensor (1) of a driver assistance system of a vehicle (10), the system having:

a reference device (2) which is arranged outside the vehicle and is used for detecting a trajectory of the vehicle (10), wherein a driving axis (6) of the vehicle (10) can be determined from the detected trajectory;

a determination device (3) for determining a sensor axis (5) of the sensor (1);

a control device (4) for the sensor (1), which is designed to determine an angle (a) between the sensor axis (5) and the travel axis (6).

9. A computer program product having program code means for performing the method according to any one of claims 1 to 7 when run on an electronic control device (4) or stored on a computer-readable data carrier.

Technical Field

The invention relates to a method for initially calibrating a sensor of a driver assistance system of a vehicle. Furthermore, the invention relates to a system for initial calibration of a sensor of a driver assistance system of a vehicle. Furthermore, the invention relates to a computer program product.

Background

In order to be able to use the driver assistance function of the sensor from the time of leaving the factory, the sensor must first be calibrated. Such calibration is currently usually performed on chassis supports with the aid of an improved axis directed to a suitable target. However, such a measurement of the travel axis and calibration in the test bench requires valuable time.

Disclosure of Invention

It is therefore an object of the present invention to provide a method for improved initial calibration of sensors of a driver assistance system.

According to a first aspect, the object is achieved by a method for initially calibrating a sensor, having the following steps:

-detecting the trajectory of the vehicle by means of a reference device arranged outside the vehicle;

-determining a sensor axis of the sensor;

-determining the axis of travel of the vehicle from the detected trajectory;

-finding the angle between the sensor axis and the driving axis.

The angle between the travel axis and the sensor axis (calibrated or uncalibrated angle of the sensor) can thus be determined by means of very short travel paths. Therefore, technically complex and inaccurate multi-point positioning (Multilateration) is not required. Advantageously, one or more driver assistance systems are available after the method is performed with the aid of the initially calibrated sensor.

According to a second aspect, the object is achieved by a system for initially calibrating a sensor of a driver assistance system, having:

a reference device arranged outside the vehicle and for detecting a trajectory of the vehicle,

wherein the axis of travel of the vehicle can be derived from the detected trajectory;

-means for determining a sensor axis of the sensor;

a control device for the sensor, which control device is designed to determine an angle between the sensor axis and the travel axis.

Advantageous embodiments of the method result from the following description.

An advantageous embodiment of the method provides for: the trajectory is detected by means of the position of the vehicle. In this way, the trajectory can be determined using a defined number of detection points of the trajectory curve of the vehicle.

A further advantageous embodiment of the method provides for: the determination of the sensor axis is carried out by means of a point target device, which is known in position and is arranged outside the vehicle, and a control device of the sensor. In this way, an exact determination of the sensor axis of the sensor can be carried out, which sensor axis is oriented in an ideal manner in the direction of travel of the vehicle. An accurate detection of the sensor axis can be achieved by an accurate known position of the point target device.

A further advantageous development of the method is characterized in that the data of the travel axis are transmitted wirelessly from the reference device to the control device of the sensor. In this way, the data can be transmitted to the control device in a highly updated and rapid manner, so that a rapid and accurate determination of the driving axis can be carried out by means of the control device.

A further advantageous development of the method is characterized in that the wireless transmission of data is carried out via a WLAN. Advantageously, a fast and efficient transport method is thereby provided, which can advantageously be used in a factory workshop. At present, WLANs are present in most vehicles in batches, so that data packets can be flashed into a control device quickly and efficiently in this way.

A further advantageous development of the method is characterized in that the angle is determined by means of a control device. Thus, the calibration angle can be obtained using an electronic control device.

A further advantageous development of the method is characterized in that the method is carried out for at least one of a video sensor, a radar sensor, a lidar sensor. Advantageously, various uses of the method are thus conceivable, wherein a different point target device is provided for each of the sensor devices mentioned.

Drawings

The invention is described in detail below with reference to two figures and with additional features and advantages. All the features described or illustrated here form the subject matter of the invention by themselves or in any combination, irrespective of the way in which the features are described or represented in the description or the drawings. The figures show:

FIG. 1 shows a schematic diagram of a system for initial calibration of sensors of a driver assistance system of a vehicle;

fig. 2 shows the principle process of an embodiment of the proposed method.

Detailed Description

Fig. 1 shows a schematic representation of a system 100 for initial calibration of a sensor 1 for a driver assistance system. A vehicle 10 with a sensor 1 (for example in the form of a video sensor, radar sensor, lidar sensor, etc.) can be seen. The sensor 1 sends a measuring beam M to a point target device 3 arranged outside the vehicle 10, the position of which is known. For radar sensors, the target device 3 has a plurality of reflective (e.g. metallic) surfaces arranged at 90 ° to one another, whereby the measuring beam M is reflected back to the sensor 1 due to multiple reflections.

Other technical configurations of the target device 3 are conceivable here for other types of sensors 1. In this way, the point target device 3 realizes the function of a point target or a corner reflector. This results in: a sensor axis 5 arranged orthogonally to the vehicle sensor 1 can be determined by means of the point target device 3, which sensor axis, when correctly oriented, has the same orientation as the travel axis 6 of the vehicle 10.

Furthermore, reference devices 2 can be seen, for example, in the form of laser trackers, which perform a highly accurate detection of the vehicle movement or the trajectory profile (trajectory) of the vehicle 10. For this purpose, the reference device 2 detects the individual positions P1 … P6 of the vehicle 10 or even the entire trajectory of the vehicle 10.

The precise positioning or position determination of the point target device 3 and the reference device 2 need only be performed once in a reference coordinate system, e.g. an orthogonal coordinate system of a manufacturing plant, not shown. The reference device 2 thus knows the position of the point target device 3 relative to the reference device 4. Advantageously, no GNSS coordinates need to be used or known in order to perform the proposed method.

The data of the trajectory profile of the vehicle detected by the reference device 2 are then transmitted wirelessly by OTA (over the air) to the control device 4 of the sensor 10, which is arranged on the vehicle 10, so that the electronic control device 4 can determine the driving axis 6 of the vehicle 10 by calculation. The calibration angle α is now calculated by the control device 4 as the angle between the sensor axis 5 and the travel axis 6.

Advantageously, the proposed method requires only a short travel section of the vehicle 10, which advantageously also enables the calibration of the sensor 1 in a spatially delimited manufacturing plant. A travel path of only about 1 to about 2 meters is sufficient, for example.

Preferably, the method can be carried out at the end of line (EOL) of manufacture, so that the vehicle 10 has a normally functioning driver assistance system at the end of line, since the sensors required for this are calibrated first or initially.

Advantageously, the method is performed significantly more resource-saving than a method by multipoint positioning, which requires about 30 to about 50 meters.

The actual procedure of the method is as follows, for example:

first, a point target device 3 is set up, the exact position of which is known to the control device 4 of the sensor 1.

The vehicle 10 then slowly (e.g., at a speed of about 5km/h to about 15 km/h) travels toward the point target device 3, wherein the travel toward the point target device 3 may be linear and/or curvilinear, and the location of the point target device is found. The sensor axis 5 can thus be determined in the manner and method described above.

At the same time, the reference device 2 (for example in the form of a laser tracker) measures the vehicle trajectory of the vehicle 10.

Alternatively, the reference device 2 may also be configured as a camera (not shown) which can recognize a marking element (not shown) arranged on the vehicle 10, wherein a position determination and a trajectory determination of the vehicle 10 can thereby be carried out.

After the short travel, the vehicle trajectory can now be transmitted to the control device 4 of the sensor 1 via OTA (for example by means of WLAN). There, the data of the vehicle axis 6 are compared or synchronized with the data of the sensor axis 5, for example, by means of a time stamp assigned to the data. Different standards (e.g. WLAN, GSM, UMTS, LTE, 5G, etc.) are conceivable for the wireless transmission of data to the control device 4.

With knowledge of the measured values of the point target device 3 from the sensor position and the measured travel axis 6, the calibration angle α can now be calculated with high accuracy, for example, by means of the control device 4.

Thereby, the calibration of the sensor 1 can be achieved with very high accuracy and in a very short time, which advantageously saves overhead in the factory and improves the robustness of the sensor 1 in normal operation.

As a result, a dynamic calibration can be achieved in this way, which allows a calibration process to be carried out without downtime and without the orientation of the travel axis during travel. For this purpose, for example, a travel from the factory to a parking lot or to a transport vehicle can also be used.

In the normal operation of the sensor 1, the calibration angle α determined by means of this method is taken into account computationally in the operation of the driver assistance system, so that advantageously no mechanical change of the orientation of the sensor 1 is necessary for the correct operation of the sensor 1. Functionally, therefore, after calibration, the sensor 1 has the same orientation as the travel axis 6 of the sensor axis 5.

Fig. 2 shows a principle process for performing the proposed method:

in step 200, the detection of the trajectory of the vehicle 10 is performed by means of a reference device 2 arranged outside the vehicle.

In step 210, the sensor axis 5 of the sensor 1 is determined.

In step 220, the determination of the travel axis 6 of the vehicle 10 is performed from the detected trajectory.

In step 230, the angle α between the sensor axis 5 and the travel axis 6 is determined.

Here, the order of performing steps 200 to 220 is arbitrary.

Advantageously, the method according to the invention can be implemented as software, which runs, for example, on the electronic control device 4. Alternatively, it is also contemplated that the method may be performed on other electronic devices disposed inside or outside of the vehicle 10. In this way, simple adaptation of the method is advantageously supported.

The person skilled in the art modifies the features of the invention and/or combines them with each other in a suitable manner without departing from the core of the invention.