AERIAL PLATFORM SYSTEM, AND RELATED METHODS

• US 20150041598A1
• Filed: 06/09/2012
• Published: 02/12/2015
• Est. Priority Date: 06/09/2011
• Status: Active Grant

• Current Assignee: LaserMotive Inc.
• Original Assignee: LaserMotive Inc.
• Inventors: Bashford, David, Kare, Jordin T., Nugent, Thomas J., Bashford, David James
• Granted Patent: US 9,800,091 B2
• Time in Patent Office: Days
• US Class Current: 244/53.R
• CPC Class Codes: B64B 1/50 Captive balloons
• CPC Class Codes: B64F 3/00 Ground installations specially adapted for captive aircraft
• CPC Class Codes: B64F 3/02 with means for supplying electricity to aircraft during flight
• CPC Class Codes: B64U 10/13 Flying platforms
• CPC Class Codes: B64U 10/16 with five or more distinct rotor axes, e.g. octocopters
• CPC Class Codes: B64U 10/17 Helicopters flying platforms B64U10/13
• CPC Class Codes: B64U 10/25 Fixed-wing aircraft VTOL aircraft B64U10/20
• CPC Class Codes: B64U 10/30 Lighter-than-air aircraft, e.g. aerostatic aircraft
• CPC Class Codes: B64U 10/60 Tethered aircraft
• CPC Class Codes: B64U 2101/30 for imaging, photography or videography
• CPC Class Codes: B64U 2201/202 using tethers for connecting to ground station
• CPC Class Codes: B64U 50/19 using electrically powered motors
• CPC Class Codes: B64U 50/31 generated by photovoltaics
• CPC Class Codes: B64U 50/34 In-flight charging photovoltaics B64U50/31
• CPC Class Codes: B64U 80/70 in containers B64U80/60 takes precedence
• CPC Class Codes: G03B 15/006 Apparatus mounted on flying objects
• CPC Class Codes: G05D 1/0055 with safety arrangements
• CPC Class Codes: G05D 1/0866 specially adapted to captive aircraft
• CPC Class Codes: H02J 2310/44 for aircrafts
• CPC Class Codes: H02J 50/30 using light, e.g. lasers
• CPC Class Codes: H02J 50/402 : the two or more transmitting or the two or more receiving devices being integrated in the same unit, e.g. power mats with several coils or antennas with several sub-antennas
• CPC Class Codes: H02J 7/0042 : characterised by the mechanical construction
• CPC Class Codes: H04B 10/807 : Optical power feeding, i.e. transmitting power using an optical signal

Abstract

An aerial platform receives power in the form of light, for example laser light, transmitted via an optical fiber from a remote optical power source. The platform comprises a receiver which converts at least a portion of the light to a different form of power, for example electric power. The platform also comprises a propulsion element which consumes the different form of power to generate propulsive thrust. Supplying power to the aerial platform from a remote source enables the platform to remain aloft longer than a battery or fuel tank carried by the platform would allow. Transmitting the power in the form of light is preferable in many cases to transmitting electric power, because electrical conductors are generally heavier than optical fibers, and are hazardous in the presence of lightning or a high-voltage power line.

Claims

1. A system comprising:

an optical transmission element;

an optical power source coupled to an end of the optical transmission element and operable to transmit optical power towards another end of the optical transmission element;

an aerial platform;

an optical power receiver attached to the aerial platform and coupled to the optical transmission element, and operable to receive optical power and convert at least a portion of the optical power into a second form of power;

a propulsion element operable to use at least a portion of the second form of power produced by the optical power receiver to propel the aerial platform;

2. The system of claim 1 wherein the optical transmission element comprises an optical fiber.

3. The system of claim 1 wherein the optical transmission element comprises at least one of the following:

a single-mode optical fiber,

a multimode step-index optical fiber,

a multimode gradient-index optical fiber,

a photonic crystal fiber, and

a plastic optical fiber.

4. The system of claim 1 wherein the aerial platform comprises at least one of the following:

a fixed-wing unmanned aerial vehicle,

a vertical-takeoff-and-landing unmanned aerial vehicle, and

an aerostat.

5. The system of claim 1 wherein the propulsion element is operable to provide at least one of the following:

vertical thrust,

horizontal thrust, and

attitude control propulsion in pitch, roll, or yaw.

6. The system of claim 1 wherein the propulsion element comprises an electric motor operatively coupled to at least one of the following:

an aircraft-type propeller,

a helicopter-type rotor, and

a ducted fan.

7. The system of claim 1 wherein the optical power receiver comprises at least one of the following:

a photovoltaic cell,

a thermophotovoltaic cell,

a thermoelectric device, and

a heat engine.

8. The system of claim 1 further comprising an energy storage element device operable to supply power to at least one propulsion element.

9. The system of claim 8 wherein the energy storage element comprises at least one of the following:

a primary battery,

a secondary battery,

a capacitor,

a supercapacitor, and

a flywheel.

10. The system of claim 1 wherein the optical power source comprises a laser.

11. The system of claim 1 wherein the optical power source comprises at least one of the following:

an incoherent array of diode lasers,

an at least partially coherent array of diode lasers,

a solid-state laser,

a diode-pumped fiber laser,

a disk laser, and

a diode pumped alkali vapor laser.

12. The system of claim 1 further comprising a tether coupled to the aerial platform, and operable to constrain the motion of the aerial platform relative to the optical power source.

13. The system of claim 1 further comprising:

a base unit, and

a tether coupled to the base unit and to the aerial platform, and operable to constrain the motion of the aerial platform relative to the base unit.

14. The system of claim 12, wherein the tether comprises at least a portion of the optical power transmission element.

15. The system of claim 12, wherein the tether comprises at least one of the following:

a strength member,

a sheath,

an optical communications fiber,

an optical fiber for illumination,

an electrical signal conductor,

an electrical power conductor, and

a static-dissipating conductive element.

16. The system of claim 12 further comprising a tether deployment mechanism operable to controllably deploy the tether.

17. The system of claim 16, wherein the tether deployment mechanism is operable to controllably retract the tether.

18. The system of claim 1, further comprising a controller operable to maintain the aerial platform in stable flight.

19. The system of claim 18, wherein the controller is operable to automatically control at least one of the following:

altitude of the aerial platform during flight,

position, relative to the optical power source, of the aerial platform during flight,

pitch angle of the aerial platform during flight,

roll angle of the aerial platform during flight,

yaw angle of the aerial platform during flight,

velocity of the aerial platform during flight,

flight path of the aerial platform during flight,

tension on a tether coupled to the aerial platform during flight.

20. The system of claim 1, further comprising a safety system operable to detect an unsafe condition.

21. The system of claim 20, wherein the safety system comprises a laser operable to detect an unsafe condition, and in response to detecting the unsafe condition is operable to prevent the emission of optical power from the optical power source.

22. A method for operating an aerial platform, the method comprising:

transmitting, via an optical transmission element, optical power from an optical power source to an optical power receiver attached to an aerial platform;

converting at least a portion of the optical power received by the optical power receiver into a form of power usable by a propulsion element to propel the aerial platform;

supplying the converted power to the propulsion element; and

propelling the aerial platform with the converted power consumed by propulsion element.

23. The method of claim 22, wherein propelling the aerial platform comprises at least one of the following:

producing vertical thrust

producing horizontal thrust, and

producing attitude control torque about an axis of the platform.

24. The method of claim 22, wherein converting at least a portion of the optical power comprises converting at least a portion of the optical power into electrical power.

25. The method of claim 22, wherein supplying the converted power comprises supplying power from an energy storage element.

26. The method of claim 22, wherein supplying the converted power comprises storing at least a portion of the converted power in an energy storage element.

27. The method of claim 25, further comprising at least one of the following:

limiting the amount of energy stored in the energy storage element such that the stored amount does not provide the propulsion element enough power to propel the aerial platform beyond a specified flight envelope while the receiver does not receive optical power, and

limiting the maximum amount of power that can be supplied by the energy storage element, such that the provided amount of power does not provide the propulsion element enough power to propel the aerial platform beyond a specified flight envelope while the receiver does not receive optical power.

28. The method of claim 22, further comprising automatically controlling at least one of the following:

altitude of the aerial platform during flight,

position, relative to the optical power source, of the aerial platform during flight,

pitch angle of the aerial platform during flight,

roll angle of the aerial platform during flight,

yaw angle of the aerial platform during flight,

velocity of the aerial platform during flight,

flight path of the aerial platform during flight,

tension on a tether coupled to the aerial platform during flight.

29. The method of claim 22, further comprising detecting an unsafe condition, and automatically performing at least one of the following in response to detecting the unsafe condition:

landing the aerial platform,

stopping the emission of optical power from the optical power source,

detaching an end of a tether from a point of attachment,

severing a tether, and

notifying a user.