FLOATING MOTOR MOUNT FOR UNMANNED AERIAL VEHICLES

• US 20170088280A1
• Filed: 09/25/2015
• Published: 03/30/2017
• Est. Priority Date: 09/25/2015
• Status: Active Grant

• Current Assignee: Amazon Technologies, Inc. (Amazon.com, Inc.)
• Original Assignee: Amazon Technologies, Inc. (Amazon.com, Inc.)
• Inventors: Skeels, Matthew Lee, Beckman, Brian C.
• Granted Patent: US 10,807,731 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: B64C 2220/00 Active noise reduction systems
• CPC Class Codes: B64C 39/024 of the remote controlled vehicle type, i.e. RPV
• CPC Class Codes: B64D 27/40 Arrangements for mounting power plants in aircraft
• CPC Class Codes: B64U 10/10 Rotorcrafts
• CPC Class Codes: B64U 10/16 with five or more distinct rotor axes, e.g. octocopters
• CPC Class Codes: B64U 2201/00 UAVs characterised by their flight controls
• CPC Class Codes: B64U 50/19 using electrically powered motors
• CPC Class Codes: B64U 50/23 with each propulsion means having an individual motor

Abstract

A motor mount assembly is provided for coupling a propeller motor to a body of an unmanned aerial vehicle (UAV). The motor mount assembly includes a floating portion and acts to attenuate frequencies of vibration from the propeller motor during operation, which modifies the corresponding noise that is produced and reduces stresses on the various components. The floating portion is surrounded on all sides by isolation portions (e.g., made of elastomers or other materials) that are held within a casing that attaches to the body of the UAV. In one implementation, the motor mount assembly is modular such that one or more of the isolation portions may be replaced with different isolation portions (e.g., having different attenuation properties), depending on the direction and nature of the vibrations from the propeller motor that are to be attenuated for a particular application.

Claims

1. An unmanned aerial vehicle (UAV), comprising:

a propeller motor;

a body; and

a motor mount assembly that couples the propeller motor to the body, the motor mount assembly comprising;

first and second elastomeric layers;

an elastomeric tube;

a floating mount, comprising;

a device attachment portion that is attached to the propeller motor; and

a floating portion that is located inside the elastomeric tube and between the first and second elastomeric layers; and

a casing comprising a body attachment portion that is attached to the body of the UAV, wherein the casing surrounds the first and second elastomeric layers and the elastomeric tube.

2. The UAV of claim 1, wherein the body attachment portion of the casing is attached to a mounting plate that is attached to the body of the UAV.

3. The UAV of claim 1, wherein at least part of the device attachment portion extends through an opening in the first elastomeric layer for attaching to the propeller motor.

4. The UAV of claim 1, wherein at least part of the device attachment portion extends through an opening in the casing for attaching to the propeller motor.

5. The UAV of claim 1, wherein the propeller motor has a range of input frequencies, and the elastomeric tube and the first and second elastomeric layers comprise natural harmonic frequencies that do not fall within the range of input frequencies of the propeller motor.

6. The UAV of claim 1, further comprising a UAV control system, including:

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;

perform a noise modification procedure during a portion of a flight of the UAV, wherein the noise modification procedure is based at least in part on current data affecting noise modifications characteristics of the motor mount assembly.

7. A mount assembly, comprising:

a floating mount comprising a floating portion and a device attachment portion, wherein the device attachment portion is configured to attach to a power device;

a casing comprising a body attachment portion, wherein the body attachment portion is configured for attachment to a body of an unmanned aerial vehicle (UAV); and

an isolation portion that is in contact with the floating portion, wherein the isolation portion is located around the floating portion and is contained within the casing.

8. The mount assembly of claim 7, wherein the power device is at least one of a motor or an engine.

9. The mount assembly of claim 7, wherein the isolation portion includes a first isolation layer, and when the device attachment portion is attached to a power device, the first isolation layer is located between the power device and the floating portion.

10. The mount assembly of claim 9, wherein the first isolation layer includes an opening through which at least part of the device attachment portion extends.

11. The mount assembly of claim 7, wherein the floating mount further comprises at least two additional device attachment portions that are configured for attachment to the power device.

12. The mount assembly of claim 7, wherein the isolation portion includes a tube of elastomeric material that is located around at least a perimeter of the floating portion.

13. The mount assembly of claim 7, wherein the isolation portion includes an elastomeric material that has been injected inside the casing around the floating portion.

14. A mount assembly for coupling a power device to a body of an unmanned aerial vehicle (UAV), the mount assembly comprising:

a floating mount comprising;

a floating portion; and

a device attachment portion that is configured for attachment to a power device having a rotating power shaft with an axis of rotation, wherein axial vibrations that are produced by the power device are generally parallel to the axis of rotation, and radial vibrations that are produced by the power device are generally perpendicular to the axis of rotation;

a first isolation portion that is in contact with the floating portion and which is configured to attenuate axial vibrations; and

a second isolation portion that is in contact with the floating portion and which is configured to attenuate radial vibrations.

15. The mount assembly of claim 14, wherein the first isolation portion includes an opening and at least part of the device attachment portion extends through the opening.

16. The mount assembly of claim 14, wherein the first isolation portion includes two isolation layers that the floating portion is located between, and the second isolation portion surrounds a perimeter of the floating portion.

17. The mount assembly of claim 14, further comprising a casing that surrounds the first and second isolation portions and that includes a body attachment portion that is configured for attachment to the body of the UAV.

18. The mount assembly of claim 17, further comprising a fastening element that when fastened attaches the body attachment portion to the body and that when unfastened allows the casing to be removed so as to provide access for replacing at least one of the first or second isolation portions.

19. The mount assembly of claim 14, wherein the power device has a range of frequencies of vibration during operation, and the first and second isolation portions comprise first and second natural harmonic frequencies, respectively, that do not fall within the range of frequencies of vibration of the power device.

20. The mount assembly of claim 19, further comprising a replacement isolation portion that is utilized to replace at least one of the first or second isolation portions and that comprises a third natural harmonic frequency that does not fall within the range of frequencies of vibration of the power device and that is different than the first or second natural harmonic frequencies.