Tethered aerial systems for data gathering

Patent metadata

Field	Value
Publication number	US-2016144958-A1
Application number	US-201414280992-A
Country	US
Kind code	A1
Filing date	May 19, 2014
Priority date	Mar 7, 2012
Publication date	May 26, 2016
Grant date	—

Abstract

A tethered unmanned aerial vehicle (“UAV”) may be outfitted with a sensor payload for data gathering. The tethered UAV may be tethered to a ground station for constricting the flight space of the UAV while also providing the option for power delivery and/or bidirectional communications. The tethered UAV's flight path may be extended by introducing one or more secondary UAVs that cooperate to extend the horizontal flight path of a primary UAV. The ground station, which may be coupled with the tethered aerial vehicle, may comprise a listening switch configured to determine a condition of the tether such that the supply of power to the tether may be terminated when tether damage or a tether severance is detected.

First claim

1 . A safety method for use with a tethered aerial vehicle having a tether with a power cable, the safety method comprising the steps of:
transmitting electrical power from a ground station to the tethered an aerial vehicle through the tether power cable; receiving at the ground station, via the tether, a tether line condition electrical signal; listening, with a listening device disposed at the ground station, to the tether line condition electrical signal to determine whether the tether line condition signal is at a predetermined acceptable level; if the tether line condition electrical signal is determined to be at the predetermined acceptable level, continue to monitor the line condition signal; if the tether line condition electrical signal is determined to be below the predetermined acceptable level, determine whether the tether is severed; if the tether is determined to be not severed, instruct the tethered aerial vehicle to (i) land at a ground station and (ii) reset the listening device; if the listening device resets, continue to listen to the line condition electrical signal; if the listening device does not reset, continue to land the tethered aerial vehicle at the ground station; if the tether is determined to be severed, (i) cut power to the tether, (ii) enter a safe-fall mode, and (iii) reset the listening device; if the listening device resets, continue to listen to the line condition electrical signal; if the listening device does not reset, continue to cut power to the tether and continue in the safe-fall mode.

2 . The safety method of claim 1 , wherein each aerial vehicle coupled to the tether enters safe-fall mode when the ground station cuts power to the tether.

3 . An unmanned tethered aerial vehicle for increasing safety during descent, the unmanned tethered aerial vehicle comprising:
a tether, wherein the tether is configured to couple with a ground station that is configured to supply power to the aerial vehicle through the tether; one or more propellers; a flight control processor in communication with the ground station, the ground station receiving a tether line condition signal; if the tether line condition electrical signal is determined by the ground station to be at or above a predetermined acceptable level, the flight control processor continues normal flight; if the tether line condition electrical signal is determined to be below the predetermined acceptable level, the ground station determines whether the tether is severed; if the ground station determines that the tether is not severed, the flight control processor instructs the tethered aerial vehicle to land at the ground station; if the ground station determines that the tether is severed, the flight control processor instructs the tethered aerial vehicle to enter a safe-fall mode; in the safe-fall mode, a descent stabilization device coupled to the flight control processor, controls the altitude of the aerial vehicle during descent; and in the safe-fall mode, a force-impact attenuator reduces peak force during ground impact when power through the tether is no longer available.

4 . The unmanned tethered aerial vehicle of claim 3 , wherein the tether is further configured to communicate data.

5 . The unmanned tethered aerial vehicle of claim 3 , wherein the force-impact attenuator is positioned on a leading porting of the aerial vehicle during descent such that the force attenuator is a first portion of the aerial vehicle to strike the ground first and attenuate the force of impact.

6 . The unmanned tethered aerial vehicle of claim 3 , wherein the descent stabilization device comprises at least one of: (i) a parachute; (ii) stabilizing fins;
or (iii) reaction wheel.

7 . The unmanned tethered aerial vehicle of claim 3 , further comprising flight control surfaces configured to steer the unmanned tethered aerial vehicle during descent.

8 . The unmanned tethered aerial vehicle of claim 7 , wherein the flight control surfaces are actuated by power generated by the propulsion system auto-rotating during descent.

Assignees

• Aurora Flight Sciences Corp

Inventors

• Woodworth Adam
• Peverill James

Classifications

• B64U2201/202

  using tethers for connecting to ground station · CPC title

• B64U2201/102

  adapted for flying in formations · CPC title

• B64F3/02

  with means for supplying electricity to aircraft during flight · CPC title

• B64C25/58

  Arrangements or adaptations of shock-absorbers or springs (shimmy-dampers B64C25/50) · CPC title

• B64C9/00

  Adjustable control surfaces or members, e.g. rudders (trimming stabilising surfaces B64C5/10) · CPC title