Device and method for testing sensors for at least one driver assistance system of a motor vehicle

Abstract

Device for checking sensors (22) for at least one driver assistance system of a motor vehicle (20) during the assembly process of the motor vehicle (20) carried out by means of an assembly hanger (30), characterized by that the device has a lifting device (10) with which the motor vehicle (20) standing on wheels (21) can be moved vertically from the assembly hanger (30) to a lower conveyor level (32) during a setting-down process, and that the device has at least one calibration device (40) having at least one Doppler generator (41) for calibrating the sensors (22), which is connected to the housing (12) of a lifting basket (11) of the lifting device (10).

Description

[0001] The invention relates to a device and a method for checking sensors for at least one driver assistance system of a motor vehicle during the assembly process of the motor vehicle carried out by means of an assembly hanger.

[0002] Driver assistance systems are used in motor vehicles to support or relieve the driver in certain driving situations. Such driver assistance systems are now used in a wide variety of forms in motor vehicles, for example as lane departure warning systems, parking assistants, emergency braking assistants, overtaking assistants, distance assistants, or turning assistants. Driver assistance systems use various sensors to detect the vehicle's surroundings, in particular ultrasonic sensors, infrared sensors, optical sensors, or radar sensors. In order for the driver assistance systems to operate correctly and properly, the driver assistance systems and thus also the associated sensors must be aligned very precisely in the vehicle.Due to the deviations or tolerances that occur during the assembly process of the motor vehicle when installing the components of the motor vehicle, a check of the installation position of the sensors is required in the final phase of the assembly process, particularly with regard to the chassis symmetry axis of the motor vehicle.

[0003] For this purpose, DE 10 2016 008 051 A1 discloses a method for calibrating at least one driver assistance system of a motor vehicle during the production of the motor vehicle. In this method, the driver assistance systems of the motor vehicle are calibrated during the purely horizontal conveyance of the motor vehicle along the conveyor system.

[0004] Furthermore, DE 10 2020 206 593 A1 describes a methodology for calibrating sensors and radar sensors, but without reference to the assembly process of a motor vehicle.

[0005] Furthermore, DE 10 2006 006 023 A1 discloses a device for testing and adjusting driver assistance systems in motor vehicles. During vehicle production, the sensors of the driver assistance systems are measured at the end of the production line while the vehicles are mounted on the assembly hanger. For this purpose, markers (targets) are placed on the floor of an assembly hall, thus outside the lifting device.

[0006] In addition, DE 10 2015 012 246 A1 describes a method for determining the installation orientation of a radar sensor of a motor vehicle, which enables a highly precise online determination of the installation orientation in elevation and azimuth of a radar sensor arranged anywhere in the motor vehicle.

[0007] Furthermore, DE 10 2004 056 400 A1 discloses a method for detecting misalignment of a distance sensor arranged in a vehicle during assembly of the vehicle, in which electromagnetic radiation is emitted by the distance sensor in a measuring device and the reflected radiation is detected and evaluated.

[0008] Finally, DE 10 2008 057 672 A1 discloses a method for calibrating sensors of a vehicle, in which the calibration is carried out during the assembly of the vehicle while the vehicle is moving on a conveyor belt using at least one reference point.

[0009] The invention is based on the object of enabling, on the basis of this known prior art, a simple check of the sensors for at least one driver assistance system of a motor vehicle during the assembly process of the motor vehicle.

[0010] This object is achieved according to the invention by a device having the features set out in claim 1.

[0011] Furthermore, this object is achieved by a method having the features set out in patent claim 10.

[0012] Advantageous further developments of the device according to the invention are part of the further patent claims.

[0013] The device according to the invention comprises a calibration device for calibrating the sensors for at least one driver assistance system of a motor vehicle and a housing of a lifting device, by means of which the motor vehicle standing on wheels is lowered or set down vertically from the assembly hanger to a lower conveyor level when the motor vehicle is at a standstill.

[0014] The calibration device is arranged on the housing of the lifting device; in particular, the calibration device is attached to a lifting basket that accommodates the motor vehicle during the lowering process of the motor vehicle or is connected to the housing of the lifting basket. For this purpose, the calibration device is attached to the housing of the lifting basket, preferably by means of at least one profile.

[0015] In order to prevent the motor vehicle, which is already on its wheels at the time of the setting-down process, from moving on its own during the setting-down process, i.e. to prevent an unwanted translational movement of the motor vehicle despite the motor vehicle actually being stationary during the setting-down process, and thus to ensure faultless functioning of the calibration device during the setting-down process, the lifting device and preferably the lifting basket of the lifting device has an adjustment device by means of which a clear positioning of the respective motor vehicle in the lifting basket and thus in the lifting device can be realized and which fixes the motor vehicle in the lifting device or in the lifting basket of the lifting device during the setting-down process.

[0016] The adjustment device can also be individually adjusted for different motor vehicles transported on the assembly hanger, which enables a consistent positioning of the motor vehicles in the lifting basket and thus in the lifting device, even for different motor vehicle types or models.

[0017] The adjustment device consists, for example, of guide rails on the lifting basket, which interact with a corresponding guide on the assembly hanger. This ensures that the vehicle is centrally positioned in the lifting basket and thus in the lifting device. It remains positioned there even during the lowering process, allowing the vehicle to be lowered to the lower conveyor level in a defined position.

[0018] To calibrate the sensors provided in the motor vehicle for at least one driver assistance system, the calibration device has at least one Doppler generator, by means of which the sensor assigned to this Doppler generator is calibrated during the lowering process of the motor vehicle. This means that the calibration takes place during the period during which the motor vehicle is transported vertically from the assembly level to the conveyor level or ground level, without the motor vehicle itself being able to move.

[0019] Preferably, each sensor provided in the motor vehicle for a driver assistance system is assigned such a Doppler generator in the calibration device. This allows all such sensors to be calibrated simultaneously and thus in a time-effective manner during the vehicle's set-down process.

[0020] Preferably, the Doppler generators of the calibration device are mounted at different positions on the lifting basket of the lifting device and thus on the housing of the lifting device and in particular are each fastened via a profile, for example via an aluminum profile, to the housing of the lifting device and in particular to the housing of the lifting basket.

[0021] In order to carry out the calibration process and thus to precisely adjust or align the Doppler generators to the assigned sensors of the driver assistance systems, the Doppler generators of the calibration device are adjustably mounted on the housing of the lifting device and in particular on the housing of the lifting basket of the lifting device.

[0022] This adjustment of the Doppler generators can be carried out mechanically by means of an adjustment mechanism or electronically by means of an adjustment electronics.

[0023] The calibration process for calibrating the sensors is initiated via a control unit or diagnostic device. The calibration process starts as soon as the vehicle has begun to lower itself vertically, or as soon as the vehicle has been transferred from the assembly sling to the lifting device or into the lifting device's lifting basket.

[0024] The sensors of the driver assistance systems to be calibrated during the vehicle's lowering process can be of any design and positioned anywhere on the vehicle. However, radar sensors, and in particular nanoradar sensors, of the vehicle are preferably calibrated during the vehicle's lowering process. These radar sensors, and in particular the nanoradar sensors of the vehicle, are provided, for example, at all four corners of the vehicle.

[0025] Advantageously, the device and method according to the invention enable sensors for at least one driver assistance system of a motor vehicle to be calibrated in a simple and time-effective manner without additional measuring stations or separate measuring devices, since the calibration process is integrated into the assembly process of the motor vehicle without the need for complex additional process steps with corresponding space requirements in the assembly area.

[0026] In the following, an embodiment of the invention is described with reference to the drawing with the Fig. 1 to 5 explained.

[0027] Showing: Fig. 1 a schematic diagram of the lifting device in a front view; Fig. 2 a schematic diagram of the lifting device in a side view; Fig. 3 a schematic representation of the lifting basket of the lifting device in a front view; Fig. 4 a schematic representation of the lifting basket of the lifting device in a side view; and Fig. 5 a schematic representation of the calibration device and its positioning with respect to the motor vehicle.

[0028] In the figures, identical or functionally equivalent elements are identified by the same reference numerals.

[0029] The Fig. 1 in a front view and in the Fig. 2, the lifting device 10, which is schematically shown in a side view, is provided during the assembly of the motor vehicle 20 at the end of the assembly process in order to lower the motor vehicle 20, which is suspended from the assembly hanger 30 and already provided with wheels 21, from the higher assembly level 31 to the lower floor area as a conveyor level 32, where the motor vehicle 20 is placed on a rubber belt 33 installed there, with which the motor vehicle 20 is automatically transported to the final acceptance of the motor vehicle 20.

[0030] During the lowering process, the assembly hanger 30 with the motor vehicle 20 attached to it, standing on wheels 21, is first transported into the lifting device 10. The assembly hanger 30 stops at a specific position in the lifting device 10 (see left half of the Fig. 1, upper motor vehicle 20), from which a type identification of the motor vehicle 20 located in the lifting device 10 is then carried out. The lifting basket 11 of the lifting device 10 is then adjusted accordingly to the wheelbase of the identified motor vehicle 20, i.e., according to the vehicle model of the motor vehicle 20.

[0031] The motor vehicle 20 is transferred from the assembly hanger 30 into the lifting basket 11 (see right half of the Fig. 1, upper motor vehicle 20) and centered in the lifting basket 11 of the lifting device 10 by means of an adjustment device 13 and fixed in the lifting basket 11, while the assembly hanger 30 is transported further and thus leaves the area of ​​the lifting device 10. Since sufficient freedom of movement has now been created, the lowering process for the motor vehicle 20 can now also be carried out by moving the lifting basket 11 of the lifting device 10 with the motor vehicle 20 located therein vertically downwards by means of an electric drive device.

[0032] Typically, such a vertical lowering process of the motor vehicle 20 takes place over a period of 10 seconds to 15 seconds.

[0033] During this time period, typically 10 to 15 seconds, for transferring the motor vehicle 20 from the assembly hanger 30 or for lowering the motor vehicle 20 in the lifting basket 11 of the lifting device 10 from the assembly level 31 to the conveying level 32, a calibration of the sensors provided in the motor vehicle 20 for at least one specific driver assistance system is carried out. For example, a calibration of the nanoradar sensors is carried out for a Side Traffic Assistant driver assistance system that prevents accidents when changing lanes and monitors the area next to and in front of the vehicle's own motor vehicle 20 on the driver's side and passenger side for the presence of critical objects, and / or a calibration of the nanoradar sensors is carried out for a Front Cross Traffic Assist driver assistance system that warns the driver of the motor vehicle 20 of crossing traffic when stationary or rolling forward in a confusing situation (intersection, exit).

[0034] As in the Fig. 3 in a front view and in the Fig. 4 schematically shown in a side view, a calibration device 40 is preferably attached to the lifting basket 11 of the lifting device 10. For example, the calibration device 40 is adjustably attached to the housing 12 of the lifting basket 11 by means of an aluminum profile 42, preferably provided for lightweight construction reasons, on the outside of the housing 12 of the lifting basket 11. For different model variants of the motor vehicle 20, other fastening devices for the calibration device 40 or other fastening variants for the calibration device 40 can also be provided if necessary, in particular in the event that the installation position of the sensors 22 and thus the angular orientation of the calibration device 40 to be provided for calibrating the sensors 22 should make this necessary.

[0035] Thus, a device is formed for checking sensors 22 for at least one driver assistance system of the motor vehicle 20, in particular during the assembly process of the motor vehicle 20 carried out by means of an assembly hanger 30. This device comprises, in particular, at least the housing 12 of the lifting device 10. With the lifting device 10, the motor vehicle 20, standing on wheels 21, can be moved vertically to a lower conveyor level 32 during a lowering process from the assembly hanger 30. The device also comprises at least the calibration device 40 for calibrating the sensors 22. This calibration device 40 is arranged on the housing 12 of the lifting device 10.

[0036] According to the Fig.5, the motor vehicle 20 has a sensor 22 designed as a nanoradar sensor at each corner 23 (front right, front left, rear right, rear left of the motor vehicle 20), so that a total of four nanoradar sensors are provided for detecting different environmental areas of the motor vehicle 20. The nanoradar sensors are arranged at the front (on the front of the motor vehicle 20) and at the rear (on the rear of the motor vehicle 20) in the area of ​​the bumpers of the motor vehicle 20, depending on the respective vehicle model, in a specific installation position and with a specific installation angle. On the front of the motor vehicle 20, the nanoradar sensors are installed, for example, at an angle of approximately 65° relative to the vehicle's axis of symmetry; on the rear of the motor vehicle 20, the nanoradar sensors are installed, for example, at an angle of approximately 45° relative to the vehicle's axis of symmetry.

[0037] The calibration device 40 preferably has a Doppler generator 41 for each sensor 22 to be calibrated. For example, four Doppler generators 41 are provided in the calibration device 40. These Doppler generators 41 of the calibration device 40 are adjusted to the installation angle of the respective associated sensor 22 by electrically or mechanically adjusting the Doppler generators 41 on the housing 12 of the lifting basket 11 or on the aluminum profile 42 on the outside of the housing 12 of the lifting basket 11.

[0038] All four sensors 22 can, for example, be calibrated simultaneously within 10 seconds by means of the calibration device 40 by activating the calibration device 40 by means of a control unit or a diagnostic device after the type recognition of the motor vehicle 20 located at a position in the lifting basket 11 of the lifting device 10 determined by the adjustment device 13, and thus starting the calibration process.

[0039] During the calibration process, each of the Doppler generators 41 preferably simulates an object moving at a constant speed. These moving simulated targets are detected by the sensors 22 and, in particular, are also differentiated from stationary targets, with each sensor 22 detecting the simulated object of its associated Doppler generator 41.

[0040] The position data, i.e., the coordinates of the Doppler generators 41 relative to the vehicle axes of the motor vehicle 20, are measured. The misalignment (skew) of the sensors 22 determined based on the difference between the target position and the measured position is corrected. To correct the misalignment and thus calibrate the sensors 22, the angle of the sensors 22 about the vertical axis 24 (z-axis) of the motor vehicle 20 is readjusted, i.e., the yaw angle of the sensors 22 is adjusted accordingly. List of reference symbols 10 Lifting device 11 Lifting basket 12 Housing lifting basket 13 Centering device / adjustment device 20 motor vehicles 21 wheels motor vehicle 22 sensors 23 Corner Motor Vehicle 24 vertical axis motor vehicle 30 assembly hangers 31 Assembly level 32 Floor area / conveyor level 33 rubber band 40 Calibration device 41 Doppler generators 42 aluminum profile

Claims

[1] Device for checking sensors (22) for at least one driver assistance system of a motor vehicle (20) during the assembly process of the motor vehicle (20) carried out by means of an assembly hanger (30), characterized by , that the device has a lifting device (10) with which the motor vehicle (20) standing on wheels (21) can be moved vertically to a lower conveyor level (32) during a setting-down process from the assembly hanger (30), and that the device has at least one calibration device (40) having at least one Doppler generator (41) for calibrating the sensors (22), which is connected to the housing (12) of a lifting basket (11) of the lifting device (10). [2] Device according to claim 1, characterized by that the lifting device (10) has an adjusting device (13) which centers and / or fixes the motor vehicle (20) in the lifting device (10) during the setting-down process. [3] Device according to claim 2, characterized by that the motor vehicle (20) is positioned in the housing (12) of the lifting basket (11) of the lifting device (10) during the lowering process. [4] Device according to one of claims 1 to 3, characterized by that a Doppler generator (41) of the calibration device (40) is provided for each sensor (22) to be calibrated. [5] Device according to one of claims 1 to 4, characterized by that the Doppler generators (41) of the calibration device (40) are mounted on the housing (12) of the lifting basket (11) of the lifting device (10) in a mechanically adjustable manner. [6] Device according to one of claims 1 to 4, characterized by that the Doppler generators (41) of the calibration device (40) are mounted electronically adjustable on the housing (12) of the lifting basket (11) of the lifting device (10). [7] Device according to one of claims 1 to 6 characterized bythat the calibration device (40) is provided for calibrating radar sensors as sensors (22) of the motor vehicle (20). [8] Method for checking sensors (22) for at least one driver assistance system of a motor vehicle (20) during the assembly process of the motor vehicle (20) carried out by means of an assembly hanger (30), characterized by , that a calibration process of the sensors (22) is carried out during a vertical lowering process of the motor vehicle (20) from an assembly level (31) to a lower conveyor level (32) by means of a lifting device (10), and that the calibration process of the sensors (22) is carried out with a calibration device (40) having at least one Doppler generator (41) which is connected to the housing (12) of a lifting basket (11) of the lifting device (10).

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