Transmitting apparatus, sound sensor and autonomous traveling vehicle

• US 20050231068A1
• Filed: 01/31/2005
• Published: 10/20/2005
• Est. Priority Date: 03/31/2004
• Status: Active Grant

• Current Assignee: Sanyo Electric Company Limited (Panasonic Holdings Corporation)
• Original Assignee: Sanyo Electric Company Limited (Panasonic Holdings Corporation)
• Inventors: Hirose, Tatsuya, Tokumaru, Tomoyoshi
• Granted Patent: US 7,098,579 B2
• Time in Patent Office: Days
• US Class Current: 310/314
• CPC Class Codes: B06B 1/0238 of a single frequency, e.g. a sine-wave
• CPC Class Codes: G01S 15/931 of land vehicles
• CPC Class Codes: G05D 1/0255 using acoustic signals, e.g. ultra-sonic singals sonar systems designed for anti-collision purposes G01S15/93
• CPC Class Codes: G05D 2201/0203 Cleaning or polishing vehicle

Abstract

A driving circuit of a transmitting apparatus drives a piezoelectric element in a frequency band different from a resonance frequency at which a vibration system including the piezoelectric element resonates the most strongly. A driving circuit of a sound sensor drives the piezoelectric element for transmitting or receiving an acoustic wave in a frequency band different from a resonance frequency at which a vibration system including the piezoelectric element resonates the most strongly. Such a transmitting apparatus is mounted as a transmitting apparatus of a sound sensor to thereby realize the sound sensor with a small measurement error. The sound sensor is adopted for traveling control and steering control of an autonomous traveling vehicle to thereby enable an autonomous traveling vehicle capable of stopping in the vicinity of an obstacle to be realized.

Claims

1. A transmitting apparatus comprising:

a piezoelectric element; and

a driving circuit for driving said piezoelectric element to transmit an acoustic wave;

wherein

said driving circuit drives said piezoelectric element in a frequency band different from a resonance frequency at which a vibration system including said piezoelectric element resonates the most strongly.

2. A sound sensor comprising:

a transmitting apparatus including a piezoelectric element, and a driving circuit for driving said piezoelectric element to transmit an acoustic wave;

a receiving apparatus including a receiver for receiving a reflected wave, from a detection-target object, of an acoustic wave transmitted by said transmitting apparatus; and

a processing circuit for acquiring information on said detection-target object on the basis of an elapsed time till the time when said receiver of said receiving apparatus receives the reflected wave from the time when said transmitting apparatus transmits an acoustic wave;

wherein said driving circuit drives said piezoelectric element in a frequency band different from a resonance frequency at which a vibration system including said piezoelectric element resonates the most strongly.

3. An autonomous traveling vehicle comprising:

a sound sensor, for detecting a detection-target object, including;

a transmitting apparatus having an piezoelectric element and a driving circuit for driving said piezoelectric element in a frequency band different from a resonance frequency at which a vibration system including said piezoelectric element resonates the most strongly to transmit an acoustic wave; and

a receiving apparatus having a receiver for receiving a reflected wave from said detection-target object of an acoustic wave transmitted from said transmitting apparatus;

a processing circuit for acquiring information on said detection-target object on the basis of an elapsed time till the time when said receiver of said receiving apparatus receives the reflected wave from the time when said transmitting apparatus transmits an acoustic wave; and

a control circuit for performing traveling control and steering control on the basis of information on said detection-target object acquired by said processing circuit.

4. The autonomous traveling vehicle as set forth in claim 3, having a function as a cleaner, wherein said traveling control and steering control by said control circuit is performed so as to travel on routes, in parallel with one pair of walls of a rectangular room facing and in parallel to each other, at predetermined intervals between adjacent routes in a direction along the other pair of walls facing and in parallel to each other, in a zigzag pattern.