Method and device for adjusting and controlling manipulators

Patent metadata

Field	Value
Publication number	US-9579792-B2
Application number	US-71918205-A
Country	US
Kind code	B2
Filing date	Nov 16, 2005
Priority date	Nov 25, 2004
Publication date	Feb 28, 2017
Grant date	Feb 28, 2017

Abstract

Methods and apparatus for adjusting and controlling a robotic manipulator based on a dynamic manipulator model. A model for gear mechanism friction torque is determined for at least one axis, based on driven axis speeds and accelerations, and on a motor temperature on the drive side of one of the motors that is associated with the axis. The model is used to determine target values, such as motor position or current. The gear mechanism friction torque that complies with the model is determined in accordance with a gear mechanism temperature.

First claim

The invention claimed is:

1. A method of adjusting or controlling an automatically controlled robotic manipulator having shafts driven by motors and associated gear mechanisms, the method comprising:
determining a gear mechanism friction torque as a function of gear mechanism temperature;
determining a target value for at least one of a motor position or a motor current associated with at least one shaft of the robotic manipulator using a dynamic manipulator model that accounts for friction torques in the gear mechanisms, the model including a gear mechanism friction torque model for the at least one shaft based on driven-side shaft velocities and shaft accelerations; and
actuating at least one motor of the robotic manipulator with a controller based on the determined target value.

2. The method of claim 1 , further comprising:
directly measuring the gear mechanism temperature.

3. The method of claim 2 , wherein measuring the gear mechanism temperature comprises measuring the temperature during operation of the manipulator.

4. The method of claim 2 , wherein measuring the gear mechanism temperature comprises measuring the temperature before operation of the manipulator.

5. The method of claim 4 , wherein determination of the gear mechanism temperature comprises minimizing the following expression relative to θG:

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Assignees

• Hietmann Gerhard
• Weiss Martin
• Kuka Roboter Gmbh

Inventors

• Hietmann Gerhard
• Weiss Martin

Classifications

• B25J9/1641 Primary

  compensation for backlash, friction, compliance, elasticity in the joints · CPC title

• G05B2219/39181

  Compensation of coulomb friction in joint · CPC title

• G05B2219/41154

  Friction, compensation for friction · CPC title

• G05B2219/41127

  Compensation for temperature variations of servo · CPC title

• G05B2219/37429

  Temperature of motor · CPC title