Object oriented motion system

• US 6,341,246 B1
• Filed: 03/26/1999
• Issued: 01/22/2002
• Est. Priority Date: 03/26/1999
• Status: Expired due to Term

• Current Assignee: KUKA Roboter GmbH (Midea Group Co., Ltd)
• Original Assignee: Kuka Development Laboratories, Inc.
• Inventors: Martin, David M., Waled, El-Houssaine, Greig, Scott D., Gerstenberger, Michael D., Mirza, Khalid
• Primary Examiner(s): Cuchlinski, Jr., William A.
• Assistant Examiner(s): Marc, McDieunel, Marc, McDieunel
• Application Number:
  US09/277,641
• Time in Patent Office: 1,033 Days
• Field of Search: 700/245, 700/246, 700/249, 700/252, 700/259, 700/261, 700/260, 700/263, 700/61, 701/23, 706/10, 706/23, 706/25, 706/28, 318/568.11, 318/568.1, 318/568.22, 318/573, 901/15, 600/204, 414/730, 414/273
• US Class Current: 700/245
• CPC Class Codes: B25J 9/161 Hardware, e.g. neural networks, fuzzy logic, interfaces, processor
• CPC Class Codes: B25J 9/1664 characterised by motion, path, trajectory planning
• CPC Class Codes: G05B 2219/36035 Special language, task programming, oop object oriented programming
• CPC Class Codes: G05B 2219/40519 Motion, trajectory planning
• CPC Class Codes: G05B 2219/49384 Control of oscillatory movement like filling a weld, weaving

Abstract

An object oriented motion system for controlling the movement of a robotic manipulator is presented. The motion system includes a trajectory generator object for producing a stream of machine joint commands. A kinematics object is operable to provide a set of robotic arm specific functions for the trajectory generator object. A servo object provides an interface to the servo system. The stream of machine motor commands are converted by the servo object to a stream of signals that drive the servo system, thereby controlling the trajectory of the robot arm.

Claims

1. A motion system for controlling the movement of a robot arm through a servo system, comprising:

an object oriented motion system implemented as a plurality of software objects each encapsulating both functional implementation code and associated internal data structures;

wherein said plurality of software objects include the following software objects;

a trajectory generator object for producing a stream of machine motor commands;

a kinematics object operable to provide as et of robot arm specific functions for said trajectory generator objects; and

as servo object for interfacing to the servo system, such that the stream of machine motor commands are converted to a stream of signals to operate the robot arm.

2. The motion system of claim 1 further comprising a calibration object activable to calibrate the robot arm.

3. The motion system of claim 1 further comprising a motion manager for controlling application logins and distributing incoming messages to the trajectory generator object.

4. The motion system of claim 1 wherein the kinematics object set of functions are selected from the group of:

forward and inverse kinematics, forward and inverse velocity calculations using full Jacobians, motor/joint space conversions, and setting/retrieving machine specific data.

5. A computer-implemented system for a trajectory generator operable to plan a trajectory for a robotic arm, comprising:

a motion object create in response to a motion request, said motion object activable to implement motion specific functions and motion specific data structures for said trajectory generator;

said motion object being operative to create a profile object for computing a speed profile for the trajectory that satisfies user requested constraints; and

a weave object for controlling the superposition of a predefined waveform upon the trajectory.

6. The system of claim 5 wherein the motion object hierarchically defines motion as a set of sub-objects operable to implement said motion specific functions and data structures.

7. The system of claim 5 further comprising a Cartesian motion object for controlling a translational motion of the trajectory.

8. The system of claim 7 wherein the Cartesian motion includes an orientation and the system further comprises an orientation object for controlling the orientation of the Catesian motion.

9. The system of claim 5 further comprising a joint motion object for controlling a joint motion of the trajectory.

10. The system of claim 7 wherein the Cartesian object further includes a Cartesian motion group object selected from the group of:

Arc, Cartesian Blend, Line, and LineDir.

11. The system of claim 9 wherein the joint object further includes a joint motion group object selected from the group of:

Joint, Joint Blend, and JointDir.