Autonomously deploying effects on water body bed

Patent metadata

Field	Value
Publication number	US-11904992-B2
Application number	US-202117236975-A
Country	US
Kind code	B2
Filing date	Apr 21, 2021
Priority date	Apr 21, 2020
Publication date	Feb 20, 2024
Grant date	Feb 20, 2024

Abstract

The invention relates to a payload frame for deploying a payload underwater. The payload frame includes at least three lead screws, each lead screw connected near a top end of the lead screw to the payload by a corresponding spherical bearing; at least three motors, each motor connected to a bottom end of one of the lead screws, the motor to rotate the lead screw through the corresponding spherical bearing; at least three feet, each foot attached to one of the motors, the feet to support and secure the payload frame on a water body bed; an accelerometer attached to the payload, the accelerometer to measure gravity vectors of the payload; and a microcontroller connected to the accelerometer and the motors. The microcontroller to receive the gravity vectors from the accelerometer and control each of the motors based on the gravity vectors to position the payload in a target orientation.

First claim

What is claimed is:

1. A payload frame for deploying a payload underwater, the payload frame comprising:
at least three lead screws, each lead screw connected near a top end of the lead screw to the payload by a corresponding spherical bearing;
at least three motors, each motor connected to a bottom end of one of the lead screws, the motor to rotate the lead screw through the corresponding spherical bearing;
at least three feet, each foot attached to one of the motors, the feet to support and secure the payload frame on a water body bed;
an accelerometer attached to the payload, the accelerometer to measure gravity vectors of the payload; and
a microcontroller connected to the accelerometer and the motors, the microcontroller to:
receive the gravity vectors from the accelerometer; and
control each of the motors based on the gravity vectors to position the payload in a target orientation.

2. The payload frame of claim 1 , wherein the target orientation is determined using a virtual bushing joint of the payload, the virtual bushing joint defining six degrees of freedom for the payload with respect to the water body bed.

3. The payload frame of claim 2 , wherein the microcontroller controls the motors by:
determining a predicted signal error for moving the payload to the target orientation;
determining an actuation command for the motors that is proportional to the signal error and based on an inverse kinematics solver for a connection between the virtual bushing joint and the payload frame; and
executing the actuation command to control each of the motors.

4. The payload frame of claim 1 , wherein each of the lead screws has a diameter of approximately 10 mm, a lead of approximately 12 mm, a right-hand thread direction, and a lead angle of approximately 50°.

5. The payload frame of claim 1 , wherein each of the spherical bearings has a rotational range of approximately plus or minus 45° around an x and y axes of the spherical bearing.

6. The payload frame of claim 1 , wherein each of the motors is connected to the one of the lead screws using a worm gear.

7. A method for deploying a payload underwater, the method comprising:
attaching the payload to a payload frame, the payload frame comprising at least three legs;
configuring the payload frame according to physical characteristics of the payload;
releasing the payload frame in a water body; and
after the payload frame reaches a water body bed, adjusting a length of the legs according to gravity vectors from an accelerometer to position the payload in a target orientation.

8. The method of claim 7 , wherein configuring the payload frame comprises modeling an adjustment in length of one of the legs to determine lead screw parameters for adjusting the length of the legs.

9. The method of claim 7 , further comprising using a virtual bushing joint of the payload to determine the target orientation, the virtual bushing joint defining six degrees of freedom for the payload with respect to the water body bed.

10. The method of claim 9 , wherein adjusting the length of the legs further comprises:
determining a predicted signal error for moving the payload to the target orientation;
determining an actuation command for the legs that is proportional to the signal error and based on an inverse kinematics solver for a connection between the virtual bushing joint and the payload frame; and
executing the actuation command to adjust each of the legs.

11. A non-transitory computer-readable medium comprising executable instructions for causing a computer processor to:
configure a payload frame according to physical characteristics of a payload, wherein the payload frame comprises at least three legs, and wherein the payload is attached to the payload frame; and
after the payload frame reaches a water body bed, adjust a length of the legs according to gravity vectors from an accelerometer to position the payload in a target orientation.

12. The non-transitory computer-readable medium of claim 11 , wherein configuring the payload frame comprises modeling an adjustment in length of one of the legs to determine lead screw parameters for adjusting the length of the legs.

13. The non-transitory computer-readable medium of claim 11 , further comprising using a virtual bushing joint of the payload to determine the target orientation, the virtual bushing joint defining six degrees of freedom for the payload with respect to the water body bed.

14. The non-transitory computer-readable medium of claim 13 , wherein adjusting the length of the legs further comprises:
determining a predicted signal error for moving the payload to the target orientation;
determining an actuation command for the legs that is proportional to the signal error and based on an inverse kinematics solver for a connection between the virtual bushing joint and the payload frame; and
executing the actuation command to adjust each of the legs.

Assignees

• Us Navy
• Us Gov Sec Navy

Inventors

• Price Christopher M
• Leary Paul R
• Bingham Brian S

Classifications

• B63G8/001 Primary

  Underwater vessels adapted for special purposes, e.g. unmanned underwater vessels; Equipment specially adapted therefor, e.g. docking stations (self-propelled or direction controlled diving chambers with mechanical link to a base B63C11/42) · CPC title

• B63G8/20

  Steering equipment (B63G8/16, B63G8/18 take precedence; steering of vessels in general B63H25/00) · CPC title

• B63G2008/004

  autonomously operating · CPC title

• B63C11/42

  with independent propulsion or direction control · CPC title

• B63G8/14

  Control of attitude or depth (of torpedoes F42B19/00) · CPC title