Method for detecting an object in a surrounding region of a motor vehicle with the aid of an ultrasonic sensor with improved filtering of ground reflections, control device, ultrasonic sensor apparatus and motor vehicle

Patent metadata

Field	Value
Publication number	US-2018239017-A1
Application number	US-201815898539-A
Country	US
Kind code	A1
Filing date	Feb 17, 2018
Priority date	Feb 17, 2017
Publication date	Aug 23, 2018
Grant date	—

Abstract

The invention relates to a method for detecting an object ( 8 ) in a surrounding region ( 9 ) of a motor vehicle ( 1 ) in which in each of a plurality of temporally sequential measurement cycles a raw signal ( 10 ) is received, which describes an ultrasonic signal of an ultrasonic sensor ( 4 ) reflected in the surrounding region ( 9 ), the raw signal ( 10 ) is compared with a predetermined ground threshold value curve ( 11 ), and a signal component ( 14 ) of the raw signal ( 10 ) that is to be tracked which exceeds the ground threshold value curve ( 11 ) is detected and assigned to the object ( 8 ), and the object ( 8 ) is tracked in the measurement cycles on the basis of the detected signal component ( 14 ) that is to be tracked, wherein to track the object ( 8 ) after recognition of the signal component ( 14 ) that is to be tracked, in the subsequent measurement cycles, signal peaks ( 13 ) of the raw signal ( 10 ) are detected, and an assignment to the object ( 8 ) is checked for the detected signal peaks ( 13 ).

First claim

1 . A method for detecting an object in a surrounding region of a motor vehicle, comprising:
in each of a plurality of temporally sequential measurement cycles, receiving a raw signal that describes an ultrasonic signal of an ultrasonic sensor reflected in the surrounding region; comparing the raw signal with a predetermined ground threshold value curve; detecting a signal component of the raw signal that is to be tracked which exceeds the ground threshold value curve and assigning the signal component to the object; and tracking the object in the measurement cycles on the basis of the detected signal component that is to be tracked, wherein to track the object after recognition of the signal component that is to be tracked, in the subsequent measurement cycles, signal peaks of the raw signal are detected, and an assignment to the object is checked for the detected signal peaks.

2 . The method according to claim 1 , wherein to recognize the signal peaks, regions of the raw signal that exceed a predetermined noise threshold value curve and which exhibit a predetermined rise are determined independently of the predetermined ground threshold value curve.

3 . The method according to claim 1 , wherein for each of the signal peaks a first probability is determined that the signal peak describes the reflection of the ultrasonic signal at the object, and a second probability is determined that the signal peak describes an interfering signal, and the assignment of the signal peak to the object is carried out with reference to the first probability and to the second probability.

4 . The method according to claim 3 , wherein a movement model that describes a movement of the object relative to the motor vehicle is determined, and the first probability is determined depending on the movement model.

5 . The method according to claim 3 , wherein the respective amplitudes of the signal peaks are determined, and the first probability and the second probability are determined depending on the respective amplitude.

6 . The method according to claim 3 , wherein the first probability is determined with reference to at least one predetermined probability density function for amplitudes of raw signals that describe reflections of ultrasonic signals at objects.

7 . The method according to claim 3 , wherein the second probability is determined with reference to at least one predetermined probability density function for amplitudes of raw signals that describe reflections of ultrasonic signals at a ground in the surrounding region.

8 . The method according to claim 7 , wherein for predetermined distances, the at least one probability density function is predetermined in each case, for each of the signal peaks a distance assigned to the signal peak is determined, and the second probability for the respective signal peak is determined with reference to the probability density function for its distance.

9 . The method according to claim 7 , wherein for an asphalted roadway and a gravel road, the at least one probability density function is predetermined in each case, and the second probability is determined depending on the type of the ground in the surrounding region.

10 . The method according to claim 9 , wherein the type of the ground in the surrounding region is determined in each measurement cycle on the basis of an assignment of the raw signal received to one of the predetermined probability density functions.

11 . The method according to claim 1 , wherein a check is made as to whether one of the signal peaks originates from a second echo of the ultrasonic signal reflected by the object, and when the signal peak describes the second echo, the signal peak is tracked as a second echo.

12 . The method according to claim 11 , wherein the signal peak is recognized as originating from the second echo when a distance that describes the signal peak has a predetermined spacing from a distance of the object.

13 . A control device for a motor vehicle, the control device being configured to perform the method according to claim 1 .

14 . An ultrasonic sensor apparatus for a motor vehicle comprising a control device according to claim 13 ; and at least one ultrasonic sensor.

15 . A motor vehicle with an ultrasonic sensor apparatus according to claim 14 .

Assignees

• Valeo Schalter & Sensoren Gmbh

Inventors

• Milschewski Tino
• Bariant Jean-Francois

Classifications

• G06F2218/10

  by analysing the shape of a waveform, e.g. extracting parameters relating to peaks · CPC title

• G06F2218/14

  by matching peak patterns · CPC title

• G06F18/2415

  based on parametric or probabilistic models, e.g. based on likelihood ratio or false acceptance rate versus a false rejection rate · CPC title

• G01S7/5273

  using digital techniques · CPC title

• G01S7/53

  Means for transforming coordinates or for evaluating data, e.g. using computers · CPC title