Unmanned aircraft system (UAS) with active energy harvesting and power management

• US 9,527,588 B1
• Filed: 09/27/2013
• Issued: 12/27/2016
• Est. Priority Date: 09/28/2012
• Status: Active Grant

• Current Assignee: Scott B. Rollefstad
• Original Assignee: Scott B. Rollefstad
• Inventors: Rollefstad, Scott B.
• Primary Examiner(s): Xavier, Valentina
• Application Number:
  US14/040,040
• Time in Patent Office: 1,187 Days
• US Class Current: 1/1
• CPC Class Codes: B64D 41/00 Power installations for auxiliary purposes
• CPC Class Codes: B64U 10/10 Rotorcrafts
• CPC Class Codes: B64U 10/13 Flying platforms
• CPC Class Codes: B64U 2201/104 using satellite radio beacon positioning systems, e.g. GPS
• CPC Class Codes: B64U 2201/20 Remote controls
• CPC Class Codes: B64U 30/20 Rotors; Rotor supports
• CPC Class Codes: B64U 30/293 Foldable or collapsible rotors or rotor supports
• CPC Class Codes: B64U 50/19 using electrically powered motors
• CPC Class Codes: B64U 50/34 In-flight charging photovoltaics B64U50/31
• CPC Class Codes: B64U 80/00 Transport or storage specially adapted for UAVs
• CPC Class Codes: G05D 1/0005 with arrangements to save energy
• CPC Class Codes: Y02T 50/40 Weight reduction
• CPC Class Codes: Y02T 50/50 On board measures aiming to increase energy efficiency

Abstract

A method of harvesting and managing energy from air currents, by small unmanned aircraft systems (UAS) having a plurality of powered and unpowered rotors, to increase the aircraft'"'"'s flight time, especially where the mission requires extensive hovering and loitering, is provided. Conventional powered rotors create lift for the aircraft. Unpowered rotors can either be: 1) Free-wheeling rotors which increase the plan form area of aircraft as they rotate, increasing lift, and reducing the power draw on the battery, and/or 2) Rotors connected to micro-generators, which serve as a brake on the unpowered rotors, create electrical power to charge the aircraft batteries or directly power the aircraft'"'"'s electronics. The invention'"'"'s folding rotor arm design results in a compact package that is easily transported by a single user (man portable). The aircraft can be removed from its protective tube, unfolded and launched for flight in less than a minute. Extended flight times, compact easily transported design, and ability to host flight software on a user'"'"'s tablet/PC result in low total cost of ownership.

Claims

1. An unmanned aircraft energy harvesting and power management system comprising:

a. a battery-powered airframe having a plurality of powered and unpowered rotors;

b. flight electronics systems for providing control and power to the powered rotors to sustain flight operations, said flight electronics systems controlling said unpowered rotors to modify plan surface area as required; and

c. an autopilot comprising a computer in electronic communication with said powered and unpowered rotors, and

d. software stored in a non-transitory computer-readable storage medium and loaded onto said computer, comprising plan form area optimization functions for minimizing power consumption by increasing total plan surface area of the aircraft when hovering, loitering, and in-flight, generating lift from air currents, thereby decreasing the power drawn from said battery.

2. The system of claim 1 wherein said software further comprises energy generation functions for directing energy from said unpowered rotors, connected to micro-generators, connected to a battery controller that determines allocation of said power to either to recharge said batteries or power the aircraft electronics.

3. The system of claim 1 wherein said plurality of rotors comprises four, six or eight rotors.

4. The system of claim 1 wherein said rotor blades have fixed or variable pitch.

5. The system of claim 1 wherein said flight electronics systems include a radio frequency link to a ground station.

6. The system of claim 1 wherein said flight electronics system comprises an on-board guidance, navigation, and control (GNC) system.

7. The system of claim 6 wherein said GNC system is based on a GPS or other inertial guidance system.

8. The system of claim 1 wherein said powered rotors comprise a rotor connected to a direct current motor in electrical communication with an Electronic Speed Control.

9. The system of claim 1 wherein said unpowered rotors comprise a free-wheeling rotor connected to said aircraft.

10. The system of claim 1 wherein said unpowered rotors comprise a rotor connected to a micro-generator which is in electrical communication with said flight electronics system.

11. The system of claim 1 wherein said airframe comprises a chassis with folding arms that pivotably connect to the chassis, an upper dome and a lower dome, landing legs and accessory support plates.

12. The system of claim 11 wherein said upper dome further comprises arm cutouts that are adapted to accommodate the arms when said arms are in a vertical position, whereby when said arms are lowered to the horizontal and said upper dome is rotated, the arms are locked into flight position.

13. The system of claim 12 wherein said chassis comprises a sensor for detecting the presence of the upper dome when in a locked position.

14. The system of claim 10 further comprising a battery optimization system that harvests power from the unpowered rotors connected to micro-generators to re-charge the battery and/or power the aircraft electronics.

15. A kit comprising the system of claim 11 in combination with a protective tube for storing and transporting said aircraft when the arms are folded.

16. The system of claim 1, further comprising an articulating knuckle connected to the airframe at one or more rotors.

17. An unmanned aircraft system comprising:

a. a battery-powered airframe having a plurality of powered and unpowered rotors, said airframe comprising a chassis with folding arms that pivotably connect to the chassis, an upper dome and a lower dome, landing legs and accessory support plates;

b. flight electronics systems including a computer in electronic communication with said powered and unpowered rotors, for providing control and power to the powered rotors to sustain flight operations, said flight electronics systems controlling said unpowered rotors to modify plan surface area as required; and

c. software stored in a non-transitory computer-readable storage medium and loaded onto said computer, comprising plan form area optimization functions for minimizing power consumption by increasing total plan surface area of the aircraft when hovering, loitering, and in-flight, generating lift from air currents, thereby decreasing the power drawn from said battery.

18. The system of claim 17 wherein said upper dome further comprises arm cutouts that are adapted to accommodate the arms when said arms are in a vertical position, whereby when said arms are lowered to the horizontal and said upper dome is rotated, the arms are locked into flight position.

19. The system of claim 18 wherein said chassis comprises a sensor for detecting the presence of the upper dome when in a locked position.

20. The system of claim 17 further comprising a battery optimization system that harvests power from the unpowered rotors connected to micro-generators to re-charge the battery and/or power the aircraft electronics.

21. A kit comprising the system of claim 17 in combination with a protective tube for storing and transporting said aircraft when the arms are folded.

22. The system of claim 17, further comprising an articulating knuckle connected to the airframe at one or more rotors.