Method of controlling a robot through a singularity

US6845295B2 · kind B2 · utility

Assignee

• FANUC ROBOTICS AMERICA CORPORATION · US

Inventors

• Sai-Kai Cheng · Rochester Hills, US
• Di Xiao · Tangxia, CN
• Chi-Keng Tsai · Bloomfield Hills, US
• H. Dean McGee · Rochester Hills, US
• Min-Ren Jean · Rochester Hills, US

Key dates

• Filing date: Mar 6, 2003
• Grant date: Jan 18, 2005
• Expiry date: Aug 6, 2023

Classification

• Technology area (CPC G): Physics
• CPC primary: G05B2219/40333
• WIPO field: Control
• WIPO sector: Instruments

Abstract

A method of controlling a robot (32) includes the steps of selecting an initial configuration from at least one of a first, second, and third sets to position a TCP at a starting point (44) along a path (33) and selecting a final configuration different than the initial configuration to position the TCP at an ending point (46). Next, the TCP moves from the starting point (44) while maintaining the initial configuration, approaches the singularity between a first point (48) and a second point (50), and selects one of the axes in response to reaching the first point (48). The angle for the selected axis is interpolated from the first point (48) to the second point (50). After the interpolation, the angles about the remaining axes are determined and positions the arms in the final configuration when the TCP reaches the second point (50) and moves to the ending point (46) while maintaining the final configuration.