Ultrasonic sensor and vehicle control system

Patent metadata

Field	Value
Publication number	US-10585191-B2
Application number	US-201816205486-A
Country	US
Kind code	B2
Filing date	Nov 30, 2018
Priority date	Dec 4, 2017
Publication date	Mar 10, 2020
Grant date	Mar 10, 2020

Abstract

An ultrasonic sensor in the invention includes an ultrasonic transmitter, an ultrasonic receiver, and a detector. The ultrasonic transmitter transmits pulse-shaped ultrasonic waves to a thin plate to excite the thin plate. The ultrasonic receiver receives direct waves and reflected waves among the ultrasonic waves propagating in the thin plate excited by the pulse-shaped ultrasonic waves, the direct waves propagating only in the thin plate, and the reflected waves radiating outward, then reflected by the object, and returning to the thin plate. The detector detects the object present near the thin plate on the basis of a difference between a time at which the ultrasonic receiver receives the direct waves and a time at which the ultrasonic receiver receives the reflected waves.

First claim

What is claimed is:

1. An ultrasonic sensor, comprising:
an ultrasonic transmitter that transmits pulse-shaped ultrasonic waves to a thin plate to excite the thin plate;
three or more ultrasonic receivers disposed on the thin plate, wherein a respective ultrasonic receiver that receives direct waves and reflected waves among the ultrasonic waves propagating in the thin plate excited by the pulse-shaped ultrasonic waves, the direct waves propagating in only the thin plate, and the reflected waves radiating outward, then reflected by an object, and returning to the thin plate; and
a detector that detects estimates a three-dimensional position of the object present near the thin plate on the basis of a difference between a respective time at which each ultrasonic receiver receives the direct waves and a respective time at which each ultrasonic receiver receives the reflected waves, and a positional relation between the ultrasonic transmitter and each of the three or more ultrasonic receivers.

2. The ultrasonic sensor according to claim 1 , wherein the ultrasonic transmitter and at least one of the three or more ultrasonic receivers are disposed on a rear surface of the thin plate.

3. The ultrasonic sensor according to claim 1 , wherein at least one of the three or more ultrasonic receivers is disposed on a front surface of the thin plate.

4. The ultrasonic sensor according to claim 1 , wherein the ultrasonic transmitter and at least one of the three or more ultrasonic receivers are disposed on a peripheral portion of the thin plate.

5. The ultrasonic sensor according to claim 1 , wherein
the ultrasonic transmitter transmits the pulse-shaped ultrasonic waves having a first frequency and the pulse-shaped ultrasonic waves having a second frequency, and
the detector detects the object on the basis of a detection result of the object using the pulse-shaped ultrasonic waves having the first frequency and a detection result of the object using the pulse-shaped ultrasonic waves having the second frequency.

6. The ultrasonic sensor according to claim 1 , further comprising a signal processor that removes a reference signal indicating a signal caused by a factor other than the object from a signal received by at least one of the three or more ultrasonic receivers and inputs the signal after the removal to the detector.

7. The ultrasonic sensor according to claim 6 , further comprising a learning unit that learns the reference signal for each of a plurality of kinds of environments, wherein the signal processor removes the learned reference signal corresponding to a current environment from the signal received by the at least one of the three or more ultrasonic receivers.

8. The ultrasonic sensor according to claim 1 , wherein the thin plate is a door of a vehicle.

9. A vehicle control system, comprising:
the ultrasonic sensor according to claim 1 ; and
a vehicle controller that controls a vehicle using a detection result of the ultrasonic sensor.

10. An ultrasonic sensor, comprising:
an ultrasonic transmitter that transmits pulse-shaped ultrasonic waves to a thin plate to excite the thin plate;
an ultrasonic receiver that receives direct waves and reflected waves among the ultrasonic waves propagating in the thin plate excited by the pulse-shaped ultrasonic waves, the direct waves propagating in only the thin plate, and the reflected waves radiating outward, then reflected by an object, and returning to the thin plate;
a detector that detects the object present near the thin plate on the basis of a difference between a time at which the ultrasonic receiver receives the direct waves and a time at which the ultrasonic receiver receives the reflected waves;
a signal processor that removes a reference signal indicating a signal caused by a factor other than the object from a signal received by the ultrasonic receiver and inputs the signal after the removal to the detector; and
a learning unit that learns the reference signal for each of a plurality of kinds of environments, wherein the signal processor removes the learned reference signal corresponding to a current environment from the signal received by the ultrasonic receiver.

Assignees

• New Japan Radio Co Ltd
• Aisin Seiki

Inventors

• Hirano Nobumitsu
• Fujiwara Hajime
• Takebuchi Kenji
• Kuchiji Hiroyuki
• Seshimoto Akira
• Yamasaki Kimiyoshi
• Taguchi Kenichi
• Otokawa Masaya

Classifications

• G01S15/04 Primary

  Systems determining presence of a target · CPC title

• G01S7/521

  Constructional features · CPC title

• E05Y2900/531

  Doors · CPC title

• E05F15/40

  Safety devices, e.g. detection of obstructions or end positions · CPC title

• B06B2201/70

  Specific application · CPC title