Utilizing acceleration information for precision landing of unmanned aerial vehicles

• US 9,448,562 B1
• Filed: 08/18/2015
• Issued: 09/20/2016
• Est. Priority Date: 08/18/2015
• Status: Active Grant

• Current Assignee: Skycatch, Inc.
• Original Assignee: Skycatch, Inc.
• Inventors: Brown, Stephan, Sirang, Behrooze
• Primary Examiner(s): O'Hara, Brian M
• Assistant Examiner(s): Kreiner, Michael
• Application Number:
  US14/829,226
• Time in Patent Office: 399 Days
• US Class Current: 1/1
• CPC Class Codes: B64U 10/14 with four distinct rotor axes, e.g. quadcopters
• CPC Class Codes: B64U 2101/30 for imaging, photography or videography
• CPC Class Codes: B64U 2201/00 UAVs characterised by their flight controls
• CPC Class Codes: B64U 2201/10 autonomous, i.e. by navigating independently from ground or air stations, e.g. by using inertial navigation systems [INS]
• CPC Class Codes: B64U 50/19 using electrically powered motors
• CPC Class Codes: B64U 70/00 Launching, take-off or landing arrangements
• CPC Class Codes: B64U 70/30 for capturing UAVs in flight by ground or sea-based arresting gear, e.g. by a cable or a net
• CPC Class Codes: B64U 70/90 Launching from or landing on platforms
• CPC Class Codes: B64U 80/70 in containers B64U80/60 takes precedence
• CPC Class Codes: G05D 1/0676 specially adapted for landing

Abstract

Systems and methods disclosed utilize acceleration information in landing an unmanned aerial vehicle. In particular, one or more embodiments include methods and systems that determine a UAV is landing, identify an acceleration spike relative to the UAV, and modify operation of the UAV while landing based on the acceleration spike. For example, in one or more embodiment, systems and methods identify an acceleration spike, compare the acceleration spike to a pattern indicative of contact with another object, and reduce the rate of rotation of rotors utilized by the UAV for flight based on the comparison of the acceleration spike to the pattern.

Claims

1. A computer-implemented method, comprising:

determining, by at least one processor, that a UAV is landing by determining a loss of information with regard to one or more transmitters associated with a landing station;

controlling an acceleration-based landing feature such that when the UAV is not landing, the acceleration-based landing feature is disabled and when the UAV is landing the acceleration-based landing feature is enabled;

based on the determination that the UAV is landing and the determination of the loss of information with regard to the one or more transmitters associated with the landing station, applying the acceleration-based landing feature by;

identifying an acceleration spike with regard to the UAV while landing;

comparing, by the at least one processor, a magnitude of the acceleration spike to a pre-defined magnitude threshold; and

based on the comparison of the magnitude of the acceleration spike to the pre-defined magnitude threshold, modifying, by the at least one processor, operation of the UAV while landing.

2. The method of claim 1, further comprising

detecting a duration of the acceleration spike;

comparing the duration of the acceleration spike to a pre-defined duration threshold; and

based on the comparison of the duration of the acceleration spike to the pre-defined duration threshold, modifying operation of the UAV while landing.

3. The method of claim 2,

wherein the pre-defined magnitude threshold is based on an acceleration magnitude associated with physical contact between the UAV and another object;

and

wherein the pre-defined acceleration duration threshold is based on an acceleration duration associated with physical contact between the UAV and another object.

4. The method of claim 1, wherein

determining that the UAV is landing comprises:

detecting a throttle level;

detecting a rotation rate;

detecting a velocity;

comparing the throttle level to a pre-defined throttle level threshold;

comparing the rotation rate to a pre-defined rotation rate threshold; and

comparing the velocity to a pre-defined velocity threshold; and

applying the acceleration-based landing feature based on the determination that the UAV is landing comprises;

applying the acceleration-based landing feature based on the comparison of the throttle level to the pre-defined throttle level threshold, the comparison of the rotation rate to the pre-defined rotation rate threshold, and the comparison of the velocity to the pre-defined velocity threshold.

5. The method of claim 1, wherein

determining that the UAV is landing comprises determining that the UAV is within a pre-defined distance of a landing site;

and

applying the acceleration-based landing feature based on the determination that the UAV is landing comprises;

applying the acceleration-based landing feature based on the determination that the UAV is within the pre-defined distance of the landing site.

6. The method of claim 1, wherein applying the acceleration-based landing feature further comprises:

determining that the UAV has made contact with another object.

7. The method of claim 1, wherein

determining that the UAV is landing comprises detecting that the UAV has crossed a boundary associated with a landing station, wherein the boundary comprises an energy emission from a landing station;

and

applying the acceleration-based landing feature based on the determination that the UAV is landing comprises;

applying the acceleration-based landing feature based on detecting that the UAV has crossed the boundary associated with the landing station, wherein the boundary comprises an energy emission from the landing station.

8. The method of claim 1, wherein modifying operation of the UAV while landing comprises at least one of:

turning off one or more motors utilized by the UAV for flight or reducing a rotational speed of one or more rotors utilized by the UAV for flight.

9. The method of claim 1, further comprising:

determining a direction of acceleration associated with the acceleration spike; and

based on the direction of the acceleration associated with the acceleration spike, modifying operation of the UAV while landing.

10. A system comprising:

a UAV comprising one or more rotors utilized by the UAV for flight;

a landing station comprising one or more transmitters;

at least one processor; and

at least one non-transitory computer readable storage medium storing instructions thereon, that, when executed by the at least one processor, cause the system to;

determine, by the at least one processor, that the UAV is landing by determining a loss of information with regard to the one or more transmitters associated with the landing station;

control an acceleration-based landing feature such that when the UAV is not landing, the acceleration-based landing feature is disabled and when the UAV is landing the acceleration-based landing feature is enabled;

based on the determination that the UAV is landing, apply the acceleration-based landing feature by;

identifying an acceleration spike with regard to the UAV;

comparing, by the at least one processor, a magnitude of the acceleration spike to a pre-defined magnitude threshold; and

based on the comparison of the magnitude of the acceleration spike to the pre-defined magnitude threshold, reducing the rotation speed of at least one of the one or more rotors utilized by the UAV for flight.

11. The system of claim 10, further comprising instructions that, when executed by the at least one processor, cause the system to:

detect a duration of the acceleration spike;

compare the duration of the acceleration spike to a pre-defined duration threshold; and

based on the comparison of the duration of the acceleration spike to the pre-defined duration threshold, modify operation of the UAV while landing.

12. The system of claim 10, wherein determining that the UAV is landing comprises:

detecting a throttle level;

detect a rotation rate;

detect a velocity;

comparing the throttle level to a pre-defined throttle level threshold;

comparing the rotation rate to a pre-defined rotation rate threshold; and

comparing the velocity to a pre-defined velocity threshold.

13. The system of claim 10, wherein applying the acceleration-based landing feature further comprises:

determining that the UAV has made contact with another object.

14. The system of claim 10,

wherein determining that the UAV is landing comprises detecting that the UAV has crossed a boundary associated with the landing station, wherein the boundary comprises an energy emission from the one or more transmitters of the landing station.

15. The system of claim 10, further comprising instructions that, when executed by the at least one processor, cause the system to:

determine a direction associated with the acceleration spike; and

based on the direction associated with the acceleration spike, modifying operation of the UAV while landing.

16. The system of claim 10,

wherein determining that a UAV is landing comprises determining that the UAV is within a pre-defined distance of the landing station.

17. A non-transitory computer readable medium storing instructions thereon that, when executed by at least one processor, cause a computer system to:

determine, by at least one processor, that a UAV is landing by determining a loss of information with regard to one or more transmitters associated with a landing station;

control an acceleration-based landing feature such that when the UAV is not landing, the acceleration-based landing feature is disabled and when the UAV is landing the acceleration-based landing feature is enabled;

based on the determination that the UAV is landing, apply the acceleration-based landing feature by;

identifying an acceleration spike with regard to the UAV while landing;

comparing, by the at least one processor, a magnitude of the acceleration spike to a pre-defined magnitude threshold; and

based on the comparison of the magnitude of the acceleration spike to the pre-defined magnitude threshold, modifying, by the at least one processor, operation of the UAV while landing.

18. The computer readable storage medium of claim 17, further comprising instructions that, when executed by the at least one processor, cause the system to:

detect a duration of the acceleration spike;

compare the duration of the acceleration spike to a pre-defined duration threshold; and

based on the comparison of the duration of the acceleration spike to the pre-defined duration threshold, modify operation of the UAV while landing.

19. The computer readable storage medium of claim 17, wherein determining that the UAV is landing comprises:

detecting a throttle level;

detecting a rotation rate;

detecting a velocity;

comparing the throttle level to a pre-defined throttle level threshold;

comparing the rotation rate to a pre-defined rotation rate threshold; and

comparing the velocity to a pre-defined velocity threshold; and

applying the acceleration-based landing feature based on the determination that the UAV is landing comprises;

applying the acceleration-based landing feature based on the comparison of the throttle level to the pre-defined throttle level threshold, the comparison of the rotation rate to the pre-defined rotation rate threshold, and the comparison of the velocity to the pre-defined velocity threshold.

20. The computer readable storage medium of claim 17, further comprising instructions that, when executed by the at least one processor, cause the system to:

determine a direction of acceleration associated with the acceleration spike; and

based on the direction of acceleration associated with the acceleration spike, modify operation of the UAV while landing.