Ground effect based surface sensing using propellers in automated aerial vehicles

• US 10,410,527 B2
• Filed: 02/26/2018
• Issued: 09/10/2019
• Est. Priority Date: 06/26/2014
• Status: Active Grant

• Current Assignee: Amazon Technologies, Inc. (Amazon.com, Inc.)
• Original Assignee: Amazon Technologies, Inc. (Amazon.com, Inc.)
• Inventors: Navot, Amir, Beckman, Brian C., Buchmueller, Daniel, Kimchi, Gur, Hensel, Fabian, Green, Scott A., Porter, Brandon William, Rault, Severan Sylvain Jean-Michel
• Primary Examiner(s): Antonucci, Anne M
• Application Number:
  US15/905,713
• Publication Number:
  US 20180190133A1
• Time in Patent Office: 561 Days
• CPC Class Codes: B64C 39/024 of the remote controlled vehicle type, i.e. RPV
• CPC Class Codes: B64D 45/04 Landing aids; Safety measures to prevent collision with earth's surface
• 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 30/20 Rotors; Rotor supports
• CPC Class Codes: G01S 2007/4975 of sensor obstruction by, e.g. dirt- or ice-coating, e.g. by reflection measurement on front-screen
• CPC Class Codes: G05D 1/0088 characterized by the autonomous decision making process, e.g. artificial intelligence, predefined behaviours using knowledge based models G06N5/00
• CPC Class Codes: G05D 1/0676 specially adapted for landing
• CPC Class Codes: G05D 1/0858 specially adapted for vertical take-off of aircraft
• CPC Class Codes: G07C 5/0808 Diagnosing performance data testing of vehicles G01M17/00; testing of electrical installation on vehicles G01R31/005
• CPC Class Codes: G08G 5/0086 for monitoring terrain radar or analogous systems specially adapted for terrain avoidance G01S13/935

Abstract

A system and method for operating an automated aerial vehicle are provided wherein influences of ground effects (e.g., which may increase the effective thrusts of propellers by interfering with the respective airflows) are utilized for sensing the ground or other surfaces. In various implementations, operating parameters of the automated aerial vehicle are monitored to determine when ground effects are influencing the parameters associated with each of the propellers, which correspondingly indicate proximities to a surface (e.g., the ground). Utilizing such techniques, proximities of different portions of an automated aerial vehicle to the ground or other surfaces may be determined (e.g., for detecting issues with an uneven landing area, a sloped ground, etc.).

Claims

1. An automated aerial vehicle, comprising:

first and second propellers;

first and second propeller motors that rotate the first and second propellers, respectively;

a power supply connected to the first and second propeller motors that provides power to the first and second propeller motors; and

a control system, comprising;

one or more processors; and

a memory coupled to the one or more processors and storing program instructions that when executed by the one or more processors cause the one or more processors to at least;

control the first propeller motor to rotate the first propeller, wherein a first parameter is associated with the first propeller and a level of the first parameter is influenced by a first ground effect, the first ground effect corresponding to a condition in which an airflow of the first propeller is directed against a surface which increases an effective thrust of the first propeller and which influences a level of the first parameter;

control the second propeller motor to rotate the second propeller, wherein a second parameter is associated with the second propeller and a level of the second parameter is influenced by a second ground effect, the second ground effect corresponding to a condition in which an airflow of the second propeller is directed against a surface which increases an effective thrust of the second propeller and which influences a level of the second parameter; and

determine that a first proximity of a first portion of the automated aerial vehicle is different than a second proximity of a second portion of the automated aerial vehicle to the surface based at least in part on a difference between a level of the first parameter as influenced by the first ground effect and a level of the second parameter as influenced by the second ground effect.

2. The automated aerial vehicle of claim 1, wherein the first and second portions of the automated aerial vehicle are front and back portions of the automated aerial vehicle, respectively.

3. The automated aerial vehicle of claim 1, wherein the program instructions when executed by the one or more processors further cause the one or more processors to monitor the levels of the first and second parameters for a specified time period to determine a consistency of the levels of the first and second parameters.

4. The automated aerial vehicle of claim 1, wherein the program instructions when executed by the one or more processors further cause the one or more processors to determine that the automated aerial vehicle is in danger of colliding with the surface based at least in part on the determination that the first proximity is different than the second proximity.

5. The automated aerial vehicle of claim 1, wherein based on the determination that the automated aerial vehicle is in danger of colliding with the surface, the program instructions when executed by the one or more processors further cause the one or more processors to control the first and second propeller motors to perform an evasive aerial maneuver to prevent the automated aerial vehicle from colliding with the surface.

6. The automated aerial vehicle of claim 1, further comprising a third propeller and a third propeller motor that rotates the third propeller, wherein the power supply provides power to the third propeller motor and the program instructions when executed by the one or more processors further cause the one or more processors to:

control the third propeller motor to rotate the third propeller, wherein a third parameter is associated with the third propeller and a level of the third parameter is influenced by a third ground effect, the third ground effect corresponding to a condition in which an airflow of the third propeller is directed against a surface which increases an effective thrust of the third propeller and which influences a level of the third parameter; and

determine that the first proximity of the first portion of the automated aerial vehicle is different than a third proximity of a third portion of the automated aerial vehicle to the surface based at least in part on a difference between a level of the first parameter as influenced by the first ground effect and a level of the third parameter as influenced by the third ground effect.

7. A system, comprising:

an automated aerial vehicle, comprising;

a plurality of propellers, wherein each propeller is rotated by a propeller motor;

a computing system, comprising;

one or more processors; and

a memory coupled to the one or more processors and storing program instructions that when executed by the one or more processors cause the one or more processors to at least;

monitor one or more parameter levels, wherein each parameter level is associated with a respective propeller and is influenced by a respective ground effect, and each ground effect corresponds to a condition in which an airflow of the respective propeller is directed against a surface which increases an effective thrust of the respective propeller and which influences the respective parameter level; and

determine that a first proximity of a first portion of the automated aerial vehicle is different than a second proximity of a second portion of the automated aerial vehicle to the surface based at least in part on the one or more parameter levels.

8. The system of claim 7, wherein the one or more parameter levels include at least a first parameter level that corresponds to a level of at least one of a voltage, current or power supplied to a propeller motor for rotating a first propeller of the plurality of propellers.

9. The system of claim 7, wherein the one or more parameter levels include at least a first parameter level that is associated with a first propeller and that is influenced by a first ground effect and the program instructions when executed by the one or more processors further cause the one or more processors to fly the automated aerial vehicle along a flight path and the first ground effect reduces the amount of power required to be supplied to the propeller motor that rotates the first propeller for flying the automated aerial vehicle while the automated aerial vehicle is proximate to the surface.

10. The system of claim 9, wherein the automated aerial vehicle further comprises an autopilot system that is utilized to control the amount of power supplied to the propeller motor that rotates the first propeller and that automatically reduces the amount of power supplied when the automated aerial vehicle is proximate to the surface.

11. The system of claim 7, wherein the plurality of propellers comprises first and second propellers and the one or more parameter levels that are monitored comprise first and second parameter levels that are associated with the first and second propellers, respectively.

12. The system of claim 7, wherein the program instructions when executed by the one or more processors further cause the one or more processors to monitor at least one parameter level of the one or more parameter levels for a specified time period to determine a consistency of the at least one parameter level.

13. The system of claim 7, wherein the first portion of the automated aerial vehicle is a front portion of the automated aerial vehicle and the second portion of the automated aerial vehicle is a back portion of the automated aerial vehicle.

14. A computer-implemented method for operating an automated aerial vehicle, comprising:

under control of one or more computing systems configured with executable instructions,

controlling a plurality of propeller motors for flying the automated aerial vehicle along a flight path, each of the propeller motors rotating a respective propeller; and

determining that a first proximity of a first portion of the automated aerial vehicle to a surface is different than a second proximity of a second portion of the automated aerial vehicle to the surface based at least in part on one or more parameter levels, wherein each parameter level of the one or more parameter levels is associated with a respective propeller and is influenced by a respective ground effect, and each ground effect corresponds to a condition in which an airflow of the respective propeller is directed against a surface which increases an effective thrust of the respective propeller and which influences the respective parameter level.

15. The computer-implemented method of claim 14, further comprising utilizing at least one of machine learning or modeling to determine a level of a parameter that corresponds to a proximity to a surface and determining the first proximity to the surface based on the determined level of the parameter.

16. The computer-implemented method of claim 14, further comprising comparing the first and second proximities to expected proximities during at least one of a landing process, a takeoff process or a flying process.

17. The computer-implemented method of claim 14, further comprising monitoring at least one parameter level of the one or more parameter levels for a specified time period to determine a consistency of the at least one parameter level.

18. The computer-implemented method of claim 14, further comprising determining that the automated aerial vehicle is in danger of colliding with the surface based at least in part on the determination that the first proximity is different than the second proximity.

19. The computer-implemented method of claim 18, further comprising controlling one or more propeller motors of the plurality of propeller motors to perform an evasive aerial maneuver to prevent the automated aerial vehicle from colliding with the surface.

20. The computer-implemented method of claim 14, wherein the plurality of propeller motors comprises first and second propeller motors that rotate first and second propellers, respectively, and the one or more parameter levels comprise first and second parameter levels that are associated with the first and second propellers, respectively.