SURROUNDINGS SENSOR WITH A MOVABLE SENSOR UNIT FOR MOTOR VEHICLES

Abstract

The invention relates to a sensor system (200, 300, 400) for a motor vehicle, comprising a sensor housing and an active or passive sensor (102) arranged therein and held on a movable sensor holder (201, 401), having a sensor technology based on radiation detection and a measurement apparatus assigned to the sensor (102) and a control apparatus, coupled to said measurement apparatus, for the sensor holder (201, 401), wherein the sensor housing has a cover (106, 301) that is signal-transmissive for the sensor (102) on its side located in the detection direction of the sensor (102), and wherein the detection range (108, 109) of the sensor (102) in the region of the signal-transmissive cover (106, 301) has a lower extent than the signal-transmissive cover (106, 301), wherein the sensor system (200, 300, 400) is characterized in that the measurement apparatus is designed such that it is suitable for checking, in the detection range of the sensor (102), whether and in which section the signal-transmissive cover (106, 301) has a region with reduced signal transmissivity (202), wherein the measurement apparatus interacts with the control apparatus in such a way that the control apparatus is able to change the position of the sensor (102) in such a way that the region with reduced signal transmissivity (202) lies outside the detection range (108, 109) of the sensor (102). The invention furthermore relates to a method for operating such a sensor system (200, 300, 400) and to a motor vehicle that is equipped with such a sensor system (200, 300, 400).

Claims

1. A sensor system for a vehicle, comprising a sensor housing and an active or passive sensor arranged therein and held on a movable sensor holder with sensor technology based on radiation wave detection as well as a measuring device associated with the sensor and a control device, coupled to said measuring device, for the sensor holder, wherein the sensor housing has a signal-transmissive cover for the sensor on its side located in the detection direction of the sensor and wherein the detection area of the sensor in the area of the signal-transmissive cover has a smaller extent than the signal-transmissive cover, wherein the measuring device is designed in such a way that it is suitable to check in the detection area of the sensor whether and in which section the signal-transmissive cover has an area with reduced signal transmissivity, wherein the measuring device cooperates with the control device in such a way that the control device can change the position of the sensor in such a way that the area with reduced signal transmissivity is outside the detection area of the sensor.

2. The sensor system of claim 1, wherein the sensor is selected from radar sensors, light sensors, lidar sensors based on lasers or light-emitting diodes and image acquisition sensors.

3. The sensor system of claim 1, wherein the sensor has a transmitting device and a separate receiving device, and wherein the transmitting device or the receiving device is fixed to the movable sensor holder or the transmitting device and the receiving device are each separately fixed to movable sensor holders.

4. The sensor system of claim 1, wherein the sensor holder is designed to be movable in all spatial directions, and rotatable or tiltable about all axes.

5. The sensor system of claim 1, wherein the sensor holder is assigned at least an electric motor, a piezoelectric element, or a hydraulic element for the movement thereof.

6. The sensor system of claim 1, wherein the sensor holder is fixed to the sensor housing.

7. The sensor system of claim 1, wherein the check of whether and in which section the signal-transmissive cover has an area with reduced signal transmissivity can be carried out by means of a computing unit assigned to the measuring device, wherein the computing unit can be operated with a data processing program, by means of which the check of whether and in which section the signal-transmissive cover has an area with reduced signal transmissivity is carried out by differential image detection using the same sensor or different sensors, wherein sensor fusion is used when using different sensors.

8. The sensor system of claim 1, wherein the measuring device and the control device are positioned independently of each other inside or outside the sensor housing.

9. The sensor system of claim 1, wherein the measuring device is designed in such a way that it can output an error signal in the event that the position of the sensor cannot be changed in such a way that the area with reduced signal transmissivity is outside the detection area of the sensor.

10. The sensor system of claim 1, wherein the sensor system is designed in such a way that the check of whether and in which section the signal-transmissive cover has an area with reduced signal transmissivity can be carried out when switching on the sensor system or at freely selectable time intervals.

11. The sensor system of claim 1, wherein a signal-transmissive inner protective cover which extends to the lateral inner walls of the housing cover is provided between the sensor and the signal-transmissive cover.

12. The sensor system of claim 1, wherein the signal-transmissive cover or the signal-transmissive inner protective cover is constructed of a transparent plastic or glass.

13. A method for operating a sensor system for a motor vehicle comprising a sensor housing and an active or passive sensor arranged therein and held on a movable sensor holder with sensor technology based on radiation detection as well as a measuring device associated with the sensor and a control device, coupled to said measuring device, for the sensor holder, wherein the sensor housing has a signal-transmissive cover for the sensor on its side located in the detection direction of the sensor and wherein the detection area of the sensor in the area of the signal-transmissive cover has a smaller extent than the signal-transmissive cover, wherein the measuring device is used to check whether and in which section of the detection area of the sensor the signal-transmissive cover has an area with reduced signal transmissivity, and if an area with reduced signal transmissivity is detected, the position of the sensor is changed by means of the control device in such a way that the area with reduced signal transmissivity is outside the detection area of the sensor.

14. The method of claim 13, wherein an area with reduced signal transmissivity is defined in that attenuation of the signal to be detected by the sensor technology of at least 5% occurs in a contiguous area of at least 1% of the detection area of the sensor on the signal-transmissive cover compared to the remaining area of the signal-transmissive cover in the detection area of the sensor.

15. A vehicle equipped with at least one sensor system of claim 1.

16. The sensor system of claim 1, wherein the sensor holder is fixed to the area of the sensor housing opposite from the signal-transmissive cover.

17. The sensor system of claim 12, wherein the transparent plastic is selected from polycarbonate, polymethyl methacrylate, polyethylene terephthalate, cellulose triacetate, amorphous polyamide, cycloolefin polymer, cycloolefin copolymer, polyethylene, polypropylene, polyvinyl alcohol or from mixtures or copolymers of these.

Description

[0048] The invention is explained in more detail based on FIGS. 1 to 3b. In the figures,

[0049] FIG. 1 shows a schematic sensor structure according to the prior art;

[0050] FIG. 2 shows a sensor according to the invention with a moving device in two positions, (2a) distorted sensor signal, (2b) undistorted sensor signal after correction of the position of the transmitter and receiver;

[0051] FIG. 3 shows another embodiment according to the invention as in FIG. 2 with two signal-transmissive covers, and

[0052] FIG. 4 shows another embodiment according to the invention with a rotation device in two positions, (4a) distorted sensor signal, (4b) undistorted sensor signal after rotation of the transmitter and receiver.

[0053] In FIG. 1, a sensor system 101 for a motor vehicle is schematically shown in a lateral sectional representation. The sensor system 101 is a parking sensor. The sensor system 101 comprises a sensor housing 110 and a sensor 102 arranged therein consisting of a transmitter 103 and a receiver 104 with a detection angle 107 which is defined by the detection area 108, 109. The sensor 102 is designed in the present case as a lidar sensor. A measuring device 105 is assigned to the sensor 102 for processing the sensor signals. The sensor housing 110 has a signal-transmissive cover 106 for the sensor 102 on its side located in the detection direction of the sensor.

[0054] FIG. 2a depicts a sensor system 200 according to the invention. This includes a horizontally movable sensor holder 201 with which the position of the sensor 102 can be changed parallel to the surface of the rear wall of the sensor system 200 as soon as signal-impairing damage 202 is detected on the signal-transmissive cover 106, which affects a first subsection 203 of the detection area 108, 109 of the sensor 102, so that the sensor 102 can only send or receive signals in a second subsection 204. In FIG. 2b the sensor system 200 from FIG. 2a is shown after the sensor 102 has been moved horizontally into such an area in which the damage 202 is outside the detection area 108, 109 of the sensor 102 and the sensor 102 is thus functional again over its entire detection angle 205.

[0055] FIGS. 3a and 3b show a development of the embodiment shown in FIGS. 2a and 2b. The main difference is that the sensor system 300 shown here additionally has, as well as a signal-transmissive cover 301, a signal-transmissive inner protective cover 302, which are each made of polycarbonate.

[0056] In FIGS. 4a and 4b, a further embodiment of the sensor system 400 according to the invention is depicted. The sensor system 400 also additionally has, as well as a signal-transmissive cover 301, a signal-transmissive inner protective cover 302. In the case of the embodiment shown here, the sensor 102 is fixed to a sensor holder designed as a rotation device 401, with which the sensor 102 can be tilted about one or two spatial axes. As a result, in the case where damage 202 occurs on the signal-transmissive cover 301, the sensor 102 can be tilted in such a way that its detection area 108, 109 is moved past the damage 202 and the sensor 102 is consequently functional again over its entire detection angle 305.

REFERENCE CHARACTER LIST

[0057] 101 sensor system (prior art) [0058] 102 sensor [0059] 103 transmitter [0060] 104 receiver [0061] 105 measuring device [0062] 106 signal-transmissive cover [0063] 107 detection angle [0064] 108 detection area [0065] 109 detection area [0066] 110 sensor housing [0067] 200 sensor system (invention) [0068] 201 horizontally movable sensor holder [0069] 202 signal-impairing damage [0070] 203 first subsection [0071] 204 second subsection [0072] 205 detection angle [0073] 300 sensor system (invention) [0074] 301 signal-transmissive cover [0075] 302 signal-transmissive inner protective cover [0076] 305 detection angle [0077] 400 sensor system (invention) [0078] 401 sensor holder configured as a rotation device