Step detection device

Patent metadata

Field	Value
Publication number	US-2025153520-A1
Application number	US-202218834060-A
Country	US
Kind code	A1
Filing date	Apr 6, 2022
Priority date	Apr 6, 2022
Publication date	May 15, 2025
Grant date	—

Abstract

An object of the present invention is to obtain a step detection device that can accurately detect a step without being affected by weather, environmental conditions, and the like. A step detection device ( 2 ) according to the present invention is a step detection device 2 that detects a step ( 20 ) in a case where a tire ( 10 ) of a vehicle ( 100 ) runs over the step, including: a plurality of strain detection elements ( 1 ) disposed on a tire inner circumferential surface of the tire at predetermined intervals in a circumferential direction of the tire; and a signal processor ( 4 ) that processes detection signals of the plurality of strain detection elements. The signal processor detects the step based on detection signals of two or more adjacent strain detection elements among the plurality of strain detection elements.

First claim

1 . A step detection device that detects a step in a case where a tire of a vehicle runs over the step, the step detection device comprising:
a plurality of strain detection elements disposed on a tire inner circumferential surface of the tire at predetermined intervals in a circumferential direction of the tire; and a signal processor that processes detection signals of the plurality of strain detection elements, wherein the signal processor detects the step based on detection signals of two or more adjacent strain detection elements among the plurality of strain detection elements.

2 . The step detection device according to claim 1 ,
wherein the signal processor has a threshold determination unit that calculates a differential value of a measurement value of each of the plurality of strain detection elements, compares the differential values of the measurement values of the plurality of strain detection elements with a preset threshold, and determines whether the differential values of the measurement values of the plurality of strain detection elements exceed the threshold; and a step determination unit that determines that the step has been detected in a case where differential values of measurement values of two or more adjacent strain detection elements among the differential values of the measurement values of the plurality of strain detection elements exceed the threshold.

3 . The step detection device according to claim 2 ,
wherein the threshold determination unit has a differential value calculation unit that obtains the measurement values by performing smoothing processing on the detection signals of the plurality of strain detection elements and calculates the differential values by time-differentiating the measurement values; a threshold setting unit that sets an upper limit threshold and a lower limit threshold; and a threshold comparison unit that determines that the differential value exceeds the threshold in a case where the differential value is outside a threshold range between the upper limit threshold and the lower limit threshold.

4 . The step detection device according to claim 3 ,
wherein the threshold setting unit has a measurement value holding unit that holds a reference value, a maximum value, and a minimum value of the measurement value during a certain period; an upper limit threshold setting unit that sets the upper limit threshold based on the reference value and the maximum value of the measurement value; and a lower limit threshold setting unit that sets the lower limit threshold based on the reference value and the minimum value of the measurement value.

5 . The step detection device according to claim 4 ,
wherein the upper limit threshold setting unit determines the upper limit threshold to be equal to or larger than a value smaller than a differential between the reference value and the maximum value of the measurement value, and the lower limit threshold setting unit determines the lower limit threshold to be smaller than a value larger than a differential between the reference value and the minimum value of the measurement value.

6 . The step detection device according to claim 1 ,
wherein the strain detection element is a semiconductor that outputs a strain amount according to a change in electric resistance.

7 . A vehicle controller that acquires a determination result of step detection from the step detection device according to claim 1 ; and
controls an accelerator or a brake of a vehicle based on the determination result.

Assignees

• Hitachi Astemo Ltd

Inventors

• Hosokawa Takeo
• Yuki Fumio
• Soma Atsuo

Classifications

• B60C2019/004

  Tyre sensors other than for detecting tyre pressure · CPC title

• B60C19/00

  Tyre parts or constructions not otherwise provided for · CPC title

• G01L5/0052

  measuring forces due to impact (G01L5/0061, G01L5/14 take precedence; impact testing of structures G01M7/08; impact testing of material G01N3/00) · CPC title

• G01L1/2268

  Arrangements for correcting or for compensating unwanted effects · CPC title

• G08G1/165

  for passive traffic, e.g. including static obstacles, trees · CPC title