Gyro-moment compensation control method and apparatus

• US 5,814,959 A
• Filed: 01/17/1996
• Issued: 09/29/1998
• Est. Priority Date: 03/31/1993
• Status: Expired due to Fees

• Current Assignee: Hitachi, Ltd.
• Original Assignee: Hitachi, Ltd.
• Inventors: Nonaka, Youichi, Sakaue, Shiyuki
• Primary Examiner(s): IP, SHIK LUEN PAUL
• Application Number:
  US08/586,318
• Time in Patent Office: 986 Days
• Field of Search: 318/560-599, 318/139, 318/649, 901/45, 901/46, 901/47, 364/424.02, 364/424.05, 364/424.01, 280/707, 280/840, 180/41, 395/83-99
• US Class Current: 318/568.11
• CPC Class Codes: B25J 9/1633 compliant, force, torque control, e.g. combined with position control

Abstract

A method and apparatus for controlling a robot which performs an operation on an object while applying any desired force to the object, and a method of controlling automobile suspensions so as to maintain the contact between the automobile and a road surface appropriately. A robot controller which controls the motion of an end effector includes a rotating body, using an external force applied to the effector. The controller beforehand measures the tensor of inertia of the rotating body, calculates the angular momentum of the rotating body on the basis of a sensed value output from a unit for sensing the rotational speed of the rotating body and the tensor of inertia of the rotating body, calculates a gyro-moment occurring in the rotating body on the basis of a sensed value output from a sensor for sensing the motion of the robot and the angular momentum of the rotating body, and uses as a control input value the external force from a sensor for sensing value minus the value of the gyro-moment. An automobile suspension is controlled by an external force applied to a wheel of the automobile, using as a control input value a sensed value output from a sensor for sensing the external force minus the value of a gyro-moment occurring in the wheel.

Claims

1. A method of controlling a robot of a type including an end effector for contacting an object comprising the step of:

sensing with a sensor a force representing external and internal force of the end effector;

obtaining a force representing a gyro-moment generated from the end effector when the robot is moved;

subtracting the obtained force from the sensored force, and obtaining a resultant force; and

controlling the robot in accordance with the resultant force which represents a contact force of the end effector with the object.

2. A controller which controls the motion of an end effector including a rotating body, using an external force applied to the end effector, comprising:

means for sensing an external force value of the external force applied to the end effector including means for measuring the tensor of inertia of the rotating body beforehand and calculating the angular momentum of the rotating body on the basis of a sensed value output from means for determining the rotational speed of the rotating body and the moment of inertia of the rotating body;

means for calculating a gyro-moment value occurring in the rotating body on the basis of a sensed value output from means for determining the motion of the rotating body and the angular momentum of the rotating body; and

means for providing as a control input value for controlling the motion of the end effector the external force value as sensed by the means for sensing minus the gyro-moment value.

3. A controller according to claim 2, wherein the controller is a robot controller.

4. A controller according to claim 2, wherein the rotating body is a wheel of an automobile.

5. A controller according to claim 4, wherein the controller controls an automobile suspension by an external force applied to the wheel of the automobile.

6. A suspension control method for controlling an automobile suspension by an external force applied to a wheel of the automobile, comprising the step of providing as a control input value for controlling the automobile suspension an external force value of the external force applied to the wheel as sensed by a sensor minus a gyro-moment value occurring in the wheel.

7. A suspension control method according to claim 6, further comprising the step of controlling the automobile suspension in accordance with the control input value.

8. An automobile suspension controlled by an external force applied to an automobile wheel, comprising:

means for sensing an external force value of the external force applied to the wheel including means for calculating the angular momentum of the wheel on the basis of a sensed value output from means for sensing the rotational speed of the wheel and the moment of inertia of the wheel;

means for calculating a gyro-moment value occurring in the wheel on the basis of a sensed value output from means for determining the attitude of the wheel and the angular momentum of the wheel; and

means for providing as a control input value for controlling the automobile suspension the external force value as sensed by the means for sensing minus the gyro-moment value occurring in the wheel.