Method of and arrangement for controlling manipulators and industrial robots

• US 4,218,172 A
• Filed: 11/09/1977
• Issued: 08/19/1980
• Est. Priority Date: 12/14/1976
• Status: Expired due to Term

• Current Assignee: Fraunhofer Gesellschaft Zur Foerderung Der Angewandten Forsching E.V.
• Original Assignee: Fraunhofer Gesellschaft Zur Foerderung Der Angewandten Forsching E.V.
• Inventors: Freund, Eckhard
• Primary Examiner(s): Eisenzopf, Reinhard J.
• Application Number:
  US05/849,825
• Time in Patent Office: 1,014 Days
• Field of Search: 214/1 CM, 318/574, 318/575, 364/478, 364/513, 364/118, 74/471 XY, 414/730, 414/750, 414/909
• US Class Current: 414/730
• CPC Class Codes: B25J 9/1638 compensation for arm bending/inertia, pay load weight/inertia
• CPC Class Codes: G05B 2219/39178 Compensation inertia arms
• CPC Class Codes: Y10S 414/122 Remote control handlers

Abstract

This disclosure is drawn to a method of and an arrangement for controllinghe rotational and translatory motions of a manipulator or industrial robot, which automatically for the entire motion and speed range, even when there is simultaneous movement of a plurality of motion actuators, permit uniform, selectible and disturbance-independent dynamic control properties for individual or all motion parameters. The invention is characterized in that for each rotational or translational motion parameter of the manipulator or industrial robot to be controlled the positioning signal of the associated motion actuator is in part generated by a control means with selectible dynamics. This controller output signal is amplified multiplicatively by the output signal of an arrangement which for a rotational motion reproduces the associated variable moment of inertia and for a translatory motion the associated mass, respectively, inclusive of the variable load mass. The controller output signal is amplified to such an extent that thereby the effect of the variable moment of inertia or of the variable mass is compensated. The other part of the positioning signal of the associated motion actuator is supplied additively by the output of a further compensation arrangement which reproduces the dynamic intercouplings with the other motion variables so that the interference effect upon simultaneously varying a plurality of motion variables is eliminated.

Claims

1. A system for controlling the rotational and translatory motions of a load using an industrial robot comprising:

(a) an actuator;

(b) shaft means for connecting said actuator to a load to be moved;

(c) first means generating a signal representative of the actual rotational and translatory motions of said shaft;

(d) second means for generating a signal representative of a predetermined sequence of rotational and translatory motions;

(e) third means for comparing the output of said first and second means;

(f) fourth means for generating a signal representative of variable moment of inertia and mass of said actuator and said load;

(g) fifth means for combining the output of said third and fourth means; and

(h) means for controlling said actuator in response to the output of said fifth means.

2. The system of claim 1 wherein said first means comprises:

(a) a rotary primary and a tachogenerator coupled to said shaft means; and

(b) an adder for combining the signal outputs of said rotary primary and said tachogenerator.

3. The system of any one of claim 1 and 2 wherein said fourth means comprises:

(a) a device for measuring the load mass;

(b) a device for measuring the extension velocity of said actuator; and

(c) a device for measuring the angular velocity of said actuator.

4. A method of controlling the rotational and translatory motions of an actuator and associated load which comprises:

(a) generating a first signal representative of the actual rotational and translatory motions of said shaft;

(b) comparing said first signal with a second signal representative of a predetermined sequence of rotational and translatory motions and providing a third signal representative thereof;

(c) measuring the variable moment of inertia and mass of said actuator and associated load and providing a fourth signal representative thereof;

(d) combining said third and fourth signals to provide a fifth signal; and

(e) controlling said actuator in response to said fifth signal.