Natator in water tank, controlling apparatus and position measuring apparatus thereon

• US 6,680,876 B2
• Filed: 08/09/2001
• Issued: 01/20/2004
• Est. Priority Date: 08/10/2000
• Status: Expired due to Fees

• Current Assignee: Mitsubishi Heavy Industries, Ltd.
• Original Assignee: Mitsubishi Heavy Industries, Ltd.
• Inventors: Terada, Yuuzi, Isomichi, Kanji
• Primary Examiner(s): Lobo, Ian J.
• Application Number:
  US09/924,479
• Publication Number:
  US 20020036953A1
• Time in Patent Office: 894 Days
• Field of Search: 367/128, 367/133, 367/907, 367/129, 342/22, 340/825.49, 340/825.69
• US Class Current: 367/128
• CPC Class Codes: G01S 5/30 Determining absolute distances from a plurality of spaced points of known location

Abstract

A radio wave transmitter transmits a transmission command to an artificial fish in a water tank. A radio wave receiver in the artificial fish outputs the received transmission command to an ultrasonic transmitter so that the ultrasonic transmitter is caused to transmit ultrasonic transmission pulses. The ultrasonic transmission pulses are received by reception devices in the water tank, and a reception signal thereof is supplied to a propagation time clock generator. The propagation time clock generator generates propagation time clock pulses according to ultrasonic propagation times from the artificial fish to the reception devices. The propagation time clock pulses are counted by a pulse counter, and a count value thereof is inputted to an arithmetic operation control portion to obtain a propagation time, thereby calculating a three-dimensional position of the artificial fish.

Claims

1. A natator in a water tank, comprising:

a radio wave receiver for receiving a signal by radio waves transmitted from the outside;

an ultrasonic transmitter for transmitting ultrasonic waves based n a signal received by said radio wave receiver; and

a natatory operation servo motor which is controlled and driven in accordance with a signal received by said radio wave receiver.

2. The natator in a water tank according to claim 1, further comprising a battery for supplying power supply for operating said radio wave receiver, said ultrasonic transmitter and said natatory operation servo motor.

3. A control apparatus of a natator in a water tank, said control apparatus comprising:

a natator which swims in a water tank;

a radio wave transmitter for transmitting a control command by radio waves to said natator;

a radio wave receiver which is provided to said natator and receives radio waves transmitted from said radio wave transmitter;

an ultrasonic transmitter for transmitting ultrasonic transmission pulses by a control command received by said radio wave receiver;

a reception device which is provided in said water tank and receives ultrasonic transmission pluses transmitted from said ultrasonic transmitter; and

a control portion for transmitting a control command from said radio wave transmitter based on an ultrasonic reception signal received by said reception device.

4. The control apparatus of a natator in a water tank according to claim 3, further comprising a natatory operation servo motor which is driven and controlled in accordance with a control command received by said radio wave receiver.

5. A position measurement apparatus of a natator in a water tank, said position measurement apparatus comprising:

a natator which swims in a water tank;

a radio wave transmitter for transmitting a transmission command by radio waves to said natator;

a radio wave receiver which is provided to said natator and receives radio waves transmitted from said radio wave transmitter;

an ultrasonic transmitter for transmitting ultrasonic transmission pulses by a transmission command received by said radio wave receiver;

at least three reception devices which are provided in said water tank and receive ultrasonic transmission pulses transmitted from said ultrasonic transmitter;

a propagation time measurement portion for measuring an ultrasonic wave propagation times from said ultrasonic transmitter to said respective reception devices based on a transmission monitor signal outputted from said radio wave transmitter and ultrasonic reception signals received by said respective reception devices; and

a position calculation portion for calculating a three-dimensional position of said natator from respective propagation times of ultrasonic waves measured by said propagation time measurement portion.

6. The position measurement apparatus of a natator in a water tank according to claim 5, wherein said propagation time measurement portion selects three reception devices from said at least three reception devices based on a reception state of said ultrasonic pulses, and measures said ultrasonic wave propagation times from said ultrasonic transmitter to said respective reception devices based on said transmission monitor signal outputted from said radio wave transmitter and said ultrasonic reception signals received by said selected three reception devices.

7. The position measurement apparatus of a natator in a water tank according to claim 5, wherein a number of said reception devices is three and said three reception devices are provided at set positions at substantially equal water depths from the surface of water in said water tank and provided in such a manner that distances between said respective set positions become substantially equal.

8. The position measurement apparatus of a natator in a water tank according to claim 5, wherein said each reception device comprises:

an ultrasonic reception device for receiving ultrasonic transmission pulses transmitted from said ultrasonic transmitter; and

a reception amplifier from amplifying ultrasonic transmission pulses received by said ultrasonic reception device and transmitting them to said propagation time measurement portion as said ultrasonic reception signal.

9. The position measurement apparatus of a natator in a water tank according to claim 5, wherein said each reception device is provided under the water in said water tank.

10. A position measurement apparatus of a natator in a water tank, said position measurement apparatus comprising:

a natator which swims in a water tank;

a radio wave transmitter for transmitting a transmission command by radio waves to said natator;

a radio wave receiver which is provided to said natator and receives radio waves transmitted from said radio wave transmitter;

an ultrasonic transmitter for transmitting ultrasonic transmission pulses by a transmission command received by said radio waver receiver;

at least three reception devices which are provided in said water tank and receive ultrasonic transmission pulses transmitted from said ultrasonic transmitter;

a propagation time clock generation portion which operates by detecting a transmission command in a transmission monitor signal outputted from said radio wave transmitter, and generates propagation time clock pulses whose number corresponds to ultrasonic propagation times from said ultrasonic transmitter to said respective reception devices;

a pulse counter for counter each propagation time clock pulse outputted from said propagation time clock generation portion;

a propagation time calculation portion for calculating an ultrasonic wave propagation time from said ultrasonic transmitter to each reception device from a pulse count value of said pulse counter; and

a position calculation portion for calculating a three-dimensional position of said natator from each ultrasonic wave propagation time calculated by said propagation time calculation portion.

11. The position measurement apparatus of a natator in a water tank according to claim 10, wherein said propagation time clock generation portion selects three reception devices from said at least three reception devices based on a reception state of said ultrasonic wave pulses, and respectively generates propagation time clock pulses whose number corresponds to ultrasonic wave propagation times from said ultrasonic transmitter to said three reception devices.

12. The position measurement apparatus of a natator in a water tank according to claim 10, wherein a number of said reception devices is three, and said three reception devices are provided at set positions at substantially equal depths from the surface of water in said water tank and are provided in such a manner that distances between said respective set positions become substantially equal.

13. The position measurement apparatus of a natator in a water tank according to claim 10, wherein said each reception device comprises:

an ultrasonic reception device for receiving ultrasonic transmission pulses transmitted from said ultrasonic transmitter; and

a reception amplifier for amplifying ultrasonic transmission pulses received by said ultrasonic reception device and transmitting them to said propagation time measurement portion as said ultrasonic reception signal.

14. The position measurement apparatus of a natator in a water tank according to claim 10, wherein said each reception device is provided under the water in said water tank.

15. The position measurement apparatus of a natator in a water tank according to claim 10, wherein said position calculation portion for calculating a three-dimensional position of said natator obtains a three-dimensional position of said natator by creating a data table showing the relationship between ultrasonic wave propagation times and a three-dimensional position of said natator in advance and comparing said ultrasonic wave propagation times calculated by said propagation time calculation portion with said data table.

16. The position measurement apparatus of a natator in a water tank according to claim 10, further comprising a storage portion for storing said data table created by said position calculation portion in advance,

wherein said position calculation portion obtains a three-dimensional position of said natator by comparing said ultrasonic wave propagation time calculation portion with said data table stored in said storage portion.