Control device for robot in inertial coordinate system

• US 5,260,629 A
• Filed: 06/24/1991
• Issued: 11/09/1993
• Est. Priority Date: 06/27/1990
• Status: Expired due to Fees

• Current Assignee: Kawasaki Jukogyo Kabushiki Kaisha
• Original Assignee: Kawasaki Jukogyo Kabushiki Kaisha
• Inventors: Katsuragawa, Takashi, Ioi, Kiyoshi, Miki, Osamu, Noro, Osamu
• Primary Examiner(s): IP, SHIK LUEN PAUL
• Application Number:
  US07/719,612
• Time in Patent Office: 869 Days
• Field of Search: 318/560-646, 901/3, 901/6, 901/9, 901/12, 901/15-23, 395/80-89, 364/150
• US Class Current: 318/568.19
• CPC Class Codes: B25J 9/1615 characterised by special kind of manipulator, e.g. planar, scara, gantry, cantilever, space, closed chain, passive/active joints and tendon driven manipulators

Abstract

The present invention discloses a control device containing a device detecting a velocity or an acceleration parameter of the main robot body. The velocity or acceleration parameters are expressed in a robot coordinate system and is detected from the detection device. The output from the detection device is even added to a desired value that is expressed in an absolute coordinate system that is in an inertial reference frame for an arm of the robot. In this way, the robot arm can be made to follow any desired path, by using desired positions in the absolute coordinate system that is an inertial coordinate system.

Claims

1. A control device for a robot referenced to an inertial coordinate system, comprising:

a robot provided with an arm in a main robot body thereof, said arm being drivable;

desired value setting means for setting a desired value expressed in an absolute coordinate system in an inertial system of said arm;

detection means for detecting at least one of a velocity and an acceleration output in a robot coordinate system of said main robot body, wherein said detection means comprises an accelerometer mounted in said main robot body and a two-stage integrator for generating both a velocity signal and a position signal from an output from said accelerometer; and

control means for correcting said desired value in response to outputs from said detection means, whereby said robot arm is driven in accordance with a corrected desired value.

2. A control device for a robot in accordance with claim 1, wherein said detection means further comprises a coordinate conversion calculation means for converting a velocity and a position expressed in said robot coordinate system into a velocity and a position expressed in said absolute coordinate system.

3. A control device for a robot in accordance with claim 1, wherein said detection means further comprises a coordinate conversion calculation means for converting an acceleration, a velocity, and a position expressed in said robot coordinate system into an acceleration, a velocity, and a position expressed in said absolute coordinate system.