Wave power

• US 8,376,790 B2
• Filed: 09/06/2011
• Issued: 02/19/2013
• Est. Priority Date: 01/20/2006
• Status: Active Grant

• Current Assignee: Liquid Robotics, Inc. (The Boeing Co.)
• Original Assignee: Liquid Robotics, Inc. (The Boeing Co.)
• Inventors: Hine, Roger G., Hine, Derek L., Rizzi, Joseph D., Kiesow, Kurt A. F., Burcham, Robert, Stutz, William A.
• Primary Examiner(s): Olson, Lars A
• Application Number:
  US13/199,646
• Publication Number:
  US 20120094556A1
• Time in Patent Office: 532 Days
• Field of Search: 114/293, 440/3, 440/9, 440/13, 440/17, 440/18, 440/19, 440/20
• US Class Current: 440/9
• CPC Class Codes: B63B 2035/006 Unmanned surface vessels, e.g. remotely controlled
• CPC Class Codes: B63B 2035/008 remotely controlled
• CPC Class Codes: B63B 2213/02 using satellite radio beacon positioning systems, e.g. the Global Positioning System GPS
• CPC Class Codes: B63B 35/00 Vessels or similar floating structures specially adapted for specific purposes and not otherwise provided for
• CPC Class Codes: B63H 1/36 swinging sideways, e.g. fishtail type
• CPC Class Codes: B63H 19/02 by using energy derived from movement of ambient water, e.g. from rolling or pitching of vessels
• CPC Class Codes: B63H 19/04 propelled by water current
• CPC Class Codes: B63H 2025/028 using remote control means, e.g. wireless control; Equipment or accessories therefor
• CPC Class Codes: B63H 2025/045 making use of satellite radio beacon positioning systems, e.g. the Global Positioning System [GPS]
• CPC Class Codes: B63H 25/02 Initiating means for steering , for slowing down, otherwise than by use of propulsive elements, or for dynamic anchoring
• CPC Class Codes: B63H 25/04 automatic, e.g. reacting to compass
• CPC Class Codes: Y02E 10/30 Energy from the sea, e.g. using wave energy or salinity gradient
• CPC Class Codes: Y02T 70/5236 Renewable or hybrid-electric solutions

Abstract

A wave-powered water vehicle includes a surface float, a submerged swimmer, and a tether which connects the float and the swimmer, so that the swimmer moves up and down as a result of wave motion. The swimmer includes one or more fins which interact with the water as the swimmer moves up and down, and generate forces which propel the vehicle forward. The vehicle, which need not be manned, can carry communication and control equipment so that it can follow a course directed by signals sent to it, and so that it can record or transmit data from sensors on the vehicle.

Claims

1. A wave-powered water vehicle which comprises

(1) a float,

(2) a swimmer, and

(3) a tether connecting the float and the swimmer;

the float, swimmer and tether being such that, when the vehicle is in still water,

(i) the float is on or near the surface of the water,

(ii) the swimmer is submerged below the float, and

(iii) the tether is under tension;

the float comprising means for reversibly altering the buoyancy of the float; and

the swimmer comprising

(2a) a swimmer body having a longitudinal axis, and

(2b) a fin system which

(a) is secured to the body,

(b) comprises a fin, and

(c) when the device is in wave-bearing water,

(i) has a configuration which changes as a result of the wave motion, and

(ii) interacts with the water to generate forces which tend to move the swimmer in a horizontal direction.

2. A water vehicle according to claim 1 in which the fin system has one or more of the following characteristics:

(A) it comprises a fin which rotates about an axis of rotation, the axis of rotation having a spatial relationship to the swimmer body which changes when the vehicle is in wave-bearing water;

(B) it comprises (i) a fin which rotates about an axis of rotation, and (ii) an elastic component which is not part of the fin, and which deforms elastically and thus influences changes in the configuration of the fin system when the vehicle is in wave-bearing water;

(C) it comprises a fin having a leading edge which comprises (i) a relatively rigid central section which has a fixed spatial relationship with the swimmer body, and (ii) relatively deformable outboard sections; and

(D) it comprises two generally laminar fins, each of which rotates about an axis of rotation generally aligned with the longitudinal axis of the swimmer body.

3. A water vehicle according to claim 1 wherein the tether has one or both of the following characteristics

(E) it comprises an elastically deformable member;

and

(F) it comprises a component which transmits data and/or electrical power.

4. A water vehicle according to claim 1 wherein the swimmer body has one or more of the following characteristics

(G) it has a substantially rigid fore section, a midsection which is relatively flexible in the vertical plane, and a substantially rigid aft section;

(H) it comprises one or more components selected from electrical equipment, communications equipment, recording equipment, control electronics, steering equipment, and sensors;

(I) it comprises a fin which influences the orientation of the swimmer body in the horizontal plane when the device is in the water-bearing water;

(J) it comprises a generally tubular housing and the fin system comprises fins which extend either side of the housing; and

(K) it comprises a generally tubular housing and vertical fin surfaces respectively adjacent to the leading end and the trailing end of the swimmer body.

5. A water vehicle according to claim 1 wherein the fin system comprises (1) a plurality of fins, (2) a rigid bar which is mounted on the swimmer body, and to which each of the fins is rotatably mounted, and (3) an elastic component which is not part of a fin and which deforms elastically and thus influences changes in the configuration of the system when the device is in wave-bearing water.

6. A water vehicle according to claim 1 wherein the fin system comprises (1) a rigid bar which is mounted on the swimmer body, (2) a generally laminar fin which is mounted on the rigid bar, and (3) an elastic component which is connected to the fin and to the rigid bar.

7. A water vehicle according to claim 1 wherein the fin system comprises a generally laminar and elastically deformable fin having a leading edge which comprises

(i) a relatively rigid central section which rotates about an axis of rotation generally transverse to the longitudinal axis of the swimmer body, and

(ii) relatively deformable outboard sections.

8. A water vehicle according to claim 1 wherein

(1) the float comprises a satellite-based position sensor and equipment for receiving radio signals, and

(2) the swimmer comprises (a) a horizontal sensor which senses direction in a horizontal plane, and (b) a steering actuator;

and

(3) the vehicle further comprises a computer system which (a) is linked to the position sensor, the horizontal sensor and the rudder, (b) contains, or is programmable to contain, instructions to control the steering actuator in response to signals received from the position sensor and the horizontal sensor, or in response to signals received from an additional sensor on the vehicle.

9. A water vehicle according to claim 1 wherein the swimmer has a center of gravity, and the tether is attached to the swimmer substantially vertically above the center of gravity;

the float has a center of buoyancy, and the tether is attached to the float substantially vertically below the center of buoyancy; and

the float has a center of drag, and the tether is attached to the float in front of the center of drag.

10. A method of utilizing wave power which comprises placing a water vehicle according to claim 1 in a body of water which has or which is expected to have water waves traveling across its surface.

11. A method of obtaining information which comprises analyzing information obtained from, or recorded by, a water vehicle as defined in claim 1.

12. A method for controlling a function of a water vehicle according to claim 1 which comprises sending signals to the water vehicle.

13. A wave-powered water vehicle which comprises

(1) a float which comprises (a) a satellite-based position sensor, (b) equipment for receiving radio signals, and (c) means for reversibly altering the buoyancy of the float,

(2) a swimmer which comprises (a) a horizontal sensor which senses direction in a horizontal plane, and (b) a steering actuator,

(3) a tether connecting the float and the swimmer, and

(4) a computer system which (a) is linked to the position sensor, the horizontal sensor and the steering actuator, (b) contains, or is programmable to contain, instructions to control the steering actuator in response to signals received from the position sensor and the horizontal sensor, or in response to signals received from an additional sensor on the vehicle;

the float, swimmer and tether being such that, when the vehicle is in still water,

(i) the float is on or near the surface of the water,

(ii) the swimmer is submerged below the float, and

(iii) the tether is under tension; and

the swimmer comprising

(2a) a swimmer body which has a longitudinal axis, and

(2b) a fin system which

(a) is secured to the body,

(b) comprises a fin, and

(c) when the device is in wave-bearing water and the float is on or near the surface of the water,

(i) has a configuration which changes as a result of the wave motion, and

(ii) interacts with the water to generate forces which tend to move the swimmer in a horizontal direction.

14. A water vehicle according to claim 13 wherein the means for reversibly altering the buoyancy of the float comprises (a) chambers which can be inflated with air to increase buoyancy and deflated to reduce buoyancy and/or (b) chambers which can be filled with water to decrease buoyancy and evacuated to increase buoyancy.

15. A water vehicle according to claim 14 wherein said chambers comprise valves which are controlled by computers responding to input from sensors on the vehicle or from radio signals.

16. A water vehicle according to claim 14 wherein the energy needed to inflate and/or to evacuate said chambers is derived from stored electrical power.

17. A water vehicle according to claim 13 wherein the fin system comprises (1) a plurality of fins, (2) a rigid bar which is mounted on the swimmer body, and to which each of the fins is rotatably mounted, and (3) an elastic component which is not part of a fin and which deforms elastically and thus influences changes in the configuration of the system when the device is in wave-bearing water.

18. A method of obtaining information which comprises analyzing information obtained from, or recorded by, a water vehicle as defined in claim 13.

19. A method for controlling a function of a water vehicle according to claim 13 which comprises sending signals to the water vehicle.

20. A method for controlling a function of a wave-powered vehicle which comprises sending radio signals to the wave-powered vehicle, wherein

(A) the wave-powered water vehicle comprises

(1) a float which comprises (a) a satellite-based position sensor and (b) equipment for receiving radio signals,

(2) a swimmer which comprises (a) a horizontal sensor which senses direction in a horizontal plane, and (b) a steering actuator,

(3) a tether connecting the float and the swimmer, and

(4) a computer system which (a) is linked to the position sensor, the horizontal sensor and the steering actuator, (b) contains, or is programmable to contain, instructions to control the steering actuator in response to signals received from the position sensor and the horizontal sensor, or in response to signals received from an additional sensor on the vehicle;

the float, swimmer and tether being such that, when the vehicle is in still water,

(i) the float is on or near the surface of the water,

(ii) the swimmer is submerged below the float, and

(iii) the tether is under tension; and

the swimmer comprising

(2a) a swimmer body which has a longitudinal axis, and

(2b) a fin system which

(a) is secured to the body,

(b) comprises a fin, and

(c) when the device is in wave-bearing water and the float is on or near the surface of the water,

(i) has a configuration which changes as a result of the wave motion, and

(ii) interacts with the water to generate forces which tend to move the swimmer in a horizontal direction; and

(B) the signals cause the wave-powered vehicle to submerge.