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CN-115916590-B - Device and method for setting the angular position of the optical axis of a motor vehicle headlight

CN115916590BCN 115916590 BCN115916590 BCN 115916590BCN-115916590-B

Abstract

The invention relates to a device for setting the angular position of the optical axis of a headlight of a motor vehicle, wherein the pitch angle is determined from the signal of at least one MEMS acceleration sensor. The device is characterized in that the MEMS acceleration sensor is a component of a control device for a headlight having a pitch angle adjustment motor provided for adjusting the angular position of the optical axis. The device is arranged to determine the longitudinal acceleration of the motor vehicle using a MEMS acceleration sensor and to use this longitudinal acceleration with a computational model for driving the pitch angle adjustment motor. An independent claim relates to a corresponding method.

Inventors

  • David Bakarin

Assignees

  • 马瑞利汽车照明(德国)有限公司

Dates

Publication Date
20260508
Application Date
20210702
Priority Date
20200706

Claims (7)

  1. 1. Device (20) for setting an angular position of an optical axis (18) of a headlight (10) of a motor vehicle, wherein the angular position is dependent on a static pitch angle of the motor vehicle, which is generated when the motor vehicle is stopped on a road or is moving linearly on a road at a constant speed, and wherein the static pitch angle is determined from signals of at least one MEMS acceleration sensor (22), characterized in that the MEMS acceleration sensor (22) is an integral part of a control device (28) of the headlight (10), wherein the headlight (10) has at least one optical module (16) with the optical axis (18) of the headlight (10) and a pitch angle adjustment motor (30) arranged for adjusting the angular position of the optical axis (18), and wherein the control device (28) is arranged to determine a longitudinal acceleration of the motor vehicle from an acceleration of the motor vehicle detected using the MEMS acceleration sensor (22) and multiply the longitudinal acceleration by a predetermined coefficient, to obtain a product, and to add the static pitch angle to the collective pitch angle adjustment motor (30) is obtained by driving the total pitch angle (18), Wherein the angular position is dependent on a static roll angle, which is produced when the motor vehicle is stopped on a road or is moving straight on a road at a constant speed, and wherein the static roll angle is determined from the signal of at least one MEMS acceleration sensor (22), and wherein the headlight (10) has a roll angle adjustment motor (32) arranged for adjusting the optical axis (18) of the light module (16), and wherein the control device (28) is arranged to determine a lateral acceleration of the motor vehicle from the acceleration of the motor vehicle detected using the MEMS acceleration sensor (22), and wherein the lateral acceleration of the motor vehicle is multiplied by a predetermined coefficient to obtain a product, and wherein the product is added to the static roll angle to obtain a total roll angle, and wherein a setting of the angular position of the optical axis (18) dependent on the total roll angle is made, and Wherein the device (20) has a bus connection (34) with a further headlight (36) and the MEMS acceleration sensor (22) is connected to a control device (38) of the further headlight (36) via the bus connection (34), wherein the control device (38) of the further headlight (36) is arranged to multiply a longitudinal acceleration of the motor vehicle detected using the MEMS acceleration sensor (22) by a predetermined coefficient to obtain a product, to add the product to the static pitch angle to obtain a collective pitch angle, and to set the angular position dependent on the collective pitch angle by driving a further pitch angle adjustment motor (40), and the control device (38) is further arranged to multiply a lateral acceleration of the motor vehicle detected using the MEMS acceleration sensor (22) by a predetermined coefficient to obtain a product, to add the product to the static roll angle to obtain a total roll angle, and to set the position of the optical axis (18) dependent on the total roll angle by driving a further roll angle adjustment motor (42).
  2. 2. The device (20) according to claim 1, wherein the pitch angle adjustment motor (30) is mechanically coupled to the light module (16) and arranged to adjust a pitch angle position of the optical axis (18).
  3. 3. The device (20) according to claim 2, wherein the roll angle adjustment motor (32) is mechanically coupled to the light module (16) and arranged to adjust a roll angle position of the optical axis (18).
  4. 4. A device (20) according to any one of claims 1 to 3, characterized in that the acceleration sensor is an acceleration sensor that detects accelerations about two axes perpendicular to each other.
  5. 5. Device (20) according to claim 4, characterized in that the control device is arranged to convert accelerations detected by the acceleration sensor around two mutually perpendicular spatial directions into a lateral acceleration and a longitudinal acceleration of the motor vehicle.
  6. 6. A device (20) according to any one of claims 1 to 3, characterized in that the acceleration sensor is an acceleration sensor that detects accelerations in three spatial directions perpendicular to each other.
  7. 7. Method for setting the angular position of the optical axis of a motor vehicle headlight, wherein the angular position is dependent on a static pitch angle, which is produced when the motor vehicle is stopped on a road or is moving straight on a road at a constant speed, and wherein the static pitch angle is determined from the signals of at least one MEMS acceleration sensor, characterized in that the longitudinal acceleration of the motor vehicle is detected using the MEMS acceleration sensor and multiplied by a predetermined coefficient, and the product is added to the static pitch angle to give a collective pitch angle, and that a setting of the angular position dependent on the collective pitch angle is performed, Wherein the angular position is also dependent on a static roll angle, which is generated when the motor vehicle is stopped on a road or is moving straight on a road at a constant speed, and wherein the static roll angle is determined from the signals of at least one MEMS acceleration sensor, and wherein the lateral acceleration of the motor vehicle is detected using the MEMS acceleration sensor and multiplied by a predetermined coefficient to obtain a product, and wherein the product is added to the static roll angle to obtain a total roll angle, and a setting of the angular position dependent on the total roll angle is made.

Description

Device and method for setting the angular position of the optical axis of a motor vehicle headlight Technical Field The invention relates to a device for setting the angular position of the optical axis of a headlight of a motor vehicle according to the preamble of claim 1. The angular position depends on the static pitch angle of the motor vehicle, which is produced when the motor vehicle is stopped on a road or is moving straight on a road at a constant speed. A static pitch angle is determined from the signals of the at least one MEMS acceleration sensor and is dependent on the load distribution and the road grade. The invention also relates to a method for setting the angular position of the optical axis of a motor vehicle headlight, wherein the angular position is dependent on a static pitch angle, which is generated when the motor vehicle is stopped on a road or is moving linearly on the road at a constant speed, and wherein the static pitch angle is determined from the signal of at least one MEMS acceleration sensor. Background Such a device and such a method are known from US8838343B 2. The position of the motor vehicle in space is described by variables, namely pitch angle, roll angle and yaw angle. These variables are defined in DIN ISO8855：2013-11,Straβenfahrzeuge,Fahrzeugdynamik und Fahrverhalten,Begriffe,(ISO 8855：2011),Berlin：Beuth,2013. Pitch describes the rotational deflection of the longitudinal axis of the vehicle about the transverse axis of the vehicle. The roll angle describes the rotational deflection of the vehicle transverse axis about the vehicle longitudinal axis. Yaw angle describes the rotational deflection of the longitudinal axis of the vehicle about the vertical axis of the vehicle. Since 1998, vehicle registration authorities have demanded compensation for the effect of load changes on the position of the optical axis of motor vehicle headlamps. For this purpose, the aim is to avoid glare for oncoming traffic participants, while at the same time providing as large an area as possible for a low beam. The device that performs this task is also called a Vertical Aiming Control (VAC) device. Manual VAC devices are known in which the driver manually sets the position of the optical axis from the instrument panel. An automatic action device (AVAC) is also known, which compensates for the static position change of the optical axis that occurs as a result of the load state change. US8838343B2 mentioned at the beginning uses MEMS acceleration sensors, but is limited to compensating for static position changes. Furthermore, dynamic AVAC devices are known which compensate for the position changes of the optical axis which occur dynamically during the driving of the motor vehicle. These devices use deflection sensors to detect the position of the optical axis. This solution is already disadvantageous because of the costs associated therewith for cabling of typically four deflection sensors. Disclosure of Invention Against this background, it is an object of the present invention to provide a device of the initially mentioned type which allows dynamic changes in the optical axis position to be compensated without having to take into account the cabling costs associated with the use of deflection sensors. This object is achieved using the features of the independent claims. The device according to the invention differs from the prior art mentioned at the outset in that the MEMS acceleration sensor is part of a control device for a headlight of a motor vehicle, wherein the headlight has at least one light module having an optical axis of the motor vehicle headlight and a pitch angle adjustment motor provided for adjusting the angular position of the optical axis, and wherein the control device is configured to determine the longitudinal acceleration of the motor vehicle from the acceleration of the motor vehicle detected using the MEMS acceleration sensor and to multiply the longitudinal acceleration by a predetermined coefficient to obtain a product, to add the product to the static pitch angle to obtain the collective pitch angle, and to set an angular position dependent on the collective pitch angle by driving the pitch angle adjustment motor. In principle, the invention is applicable to all types of headlamps for which a vertical setting device is intended. In the case of such a headlight, the emission direction of the light module is generally set. The method according to the invention is characterized in that the longitudinal acceleration of the motor vehicle is detected using a MEMS acceleration sensor and multiplied by a predetermined coefficient to obtain a product, and the product is added to the static pitch angle to obtain the collective pitch angle, and a setting is made in dependence on the angular position of the collective pitch angle. With respect to the apparatus, it is preferable that the pitch angle adjusting motor is mechanically coupled to the optical module and is arr