Method of controlling a vehicle to make a combination of arbitrary translational and rotational motions

• US 5,719,762 A
• Filed: 11/06/1995
• Issued: 02/17/1998
• Est. Priority Date: 11/06/1995
• Status: Expired due to Fees

• Current Assignee: the united states of america as represented by the secretary of the navy
• Original Assignee: the united states of america as represented by the secretary of the navy
• Inventors: Kanayama, Yutaka John
• Primary Examiner(s): NGUYEN, TAN QUANG
• Application Number:
  US08/553,904
• Time in Patent Office: 834 Days
• Field of Search: 364/424.027, 364/424.028, 364/424.029, 364/424.031, 364/424.051, 364/424.052, 364/424.098, 180/248, 180/249, 180/411, 180/413, 180/421, 180/422, 180/6.48, 180/6.6, 180/6.62, 180/8.7, 318/568.12, 318/568.19
• US Class Current: 701/23
• CPC Class Codes: B62D 61/12 with variable number of ground engaging wheels, e.g. with some wheels arranged higher than others, or with retractable wheels for manoeuvring purposes only B60S

Abstract

A method of controlling a rotary vehicle to navigate a heading using a conation of translational and rotational motions by a plurality of driving-steering wheels controlling the motion in three degrees of freedom for a manned or unmanned vehicle having at least two drive-steering wheels, wherein a drive-steering wheel is a wheel with its heading orientation and driving velocity positively controlled, wherein a global motion is a vehicle trajectory with vehicle orientation from the initial position (with orientation) to a final destination (with orientation), which comprises comparing a global motion selected to the vehicle'"'"'s body position and orientation to compute a motion instruction in three degrees of freedom, the acceleration, path of curvature, and rotation rate, collectively known as the motion command then converting the motion command into a translational speed, a translational direction, and a rotational rate and converting the translational speed, the translational direction and the rotational rate into the direction and driving speed for each independent drive-steering wheel.

Claims

1. A method of controlling the motion in three degrees of freedom for a manned or unmanned vehicle having at least two drive-steering wheels, wherein a drive-steering wheel is a wheel with its heading orientation and driving velocity positively controlled, wherein a global motion is a vehicle trajectory with vehicle orientation from the initial position (with orientation) to a final destination (with orientation), which comprises:

(a) comparing a global motion selected to the vehicle'"'"'s body position and orientation to compute a motion instruction in three degrees of freedom, the acceleration, path curvature, and rotation rate, collectively known as the motion command;

(b) converting the motion command into a translational speed, a translational direction, and a rotational rate; and

(c) converting the translational speed, the translational direction and the rotational rate into the direction and driving speed for each independent drive-steering wheel.

2. A method of controlling the motion in three degrees of freedom for a manned or unmanned vehicle having at least two drive-steering wheels, wherein a drive-steering wheel is a wheel with its heading orientation and driving velocity positively controlled, wherein a global motion is a vehicle trajectory with vehicle orientation from the initial position (with orientation) to a final destination (with orientation), which comprises:

(a) selecting the desired type of a global (body) motion in three degrees of freedom for the vehicle;

(b) initializing the vehicle controller and drive motors;

(c) repeating a sequence of operations at a constant time interval until the global motion is completed, where the sequence comprises;

(d) sensing the shaft encoders of the drive motors to compute the new heading orientation and the incremental motion against the ground on each drive-steering wheel;

(e) computing the vehicle'"'"'s incremental translational and rotational motion by the results of step (d);

(f) computing the vehicle'"'"'s updated body position and orientation from the results of step (e);

(g) comparing the global motion selected in step (a) to the vehicle'"'"'s updated body position and orientation resulting from step (f) to compute a motion instruction in three degrees of freedom, the acceleration, path curvature, and rotation rate, collectively known as the motion command;

(h) converting the motion command into the translational speed, the translational direction, and the rotational rate;

(i) converting the translational speed, the translational direction and the rotational rate into the direction and driving speed for each independent drive-steering wheel;

(j)) converting the direction and driving speed into two separate motor commands for each drive-steering wheel;

(k) sending the two commands to two motors for each wheel;

(l) returning to step (d) if the global motion is not completed; and

(m) stopping the vehicle when the global motion is completed.