Robert Foster Platt

US Patent:

8060250, Nov 15, 2011

Filed:

Dec 15, 2008

Appl. No.:

12/335153

Inventors:

Matthew J. Reiland - Oxford MI, US
Robert Platt - Houston TX, US
Muhammad E. Abdallah - Houston TX, US
Brian Hargrave - Dickerson TX, US

Assignee:

GM Global Technology Operations LLC - Detroit MI
The United States of America as represented by the Administrator of the National Aeronautics and Space Administrations - Washington DC

International Classification:

G06F 19/00

US Classification:

700245, 901 2, 901 11, 901 14, 901 19, 901 21, 901 29

Abstract:

A system and method for controlling tendon-driven manipulators that provide a closed-loop control of joint torques or joint impedances without inducing dynamic coupling between joints. The method includes calculating tendon reference positions or motor commands by projecting a torque error into tendon position space using a single linear operation. The method calculates this torque error using sensed tendon tensions and a reference torque and internal tension. The method can be used to control joint impedance by calculating the reference torque based on a joint position error. The method limits minimum and maximum tendon tensions by projecting the torque error into the tendon tension space and then projecting ii back into joint space.

US Patent:

8525460, Sep 3, 2013

Filed:

Feb 2, 2010

Appl. No.:

12/698832

Inventors:

Matthew J. Reiland - Oxford MI, US
Brian Hargrave - Dickenson TX, US
Robert Platt - Houston TX, US
Muhammad E. Abdallah - Houston TX, US
Frank Noble Permenter - Webster TX, US

Assignee:

GM Global Technology Operations LLC - Detroit MI
The United States of America as represented by the Administrator of the National Aeronautics and Space Administration - Washington DC

International Classification:

H02P 7/00

US Classification:

318432, 7447312, 7449001, 7449003, 7449005, 267 69, 267277, 267278, 267279, 318560, 318625, 318630, 318652, 31840014

Abstract:

An SEA architecture for controlling the torque applied by an SEA that has particular application for controlling the position of a robot link. The SEA architecture includes a motor coupled to one end of an elastic spring and a load coupled to an opposite end of the elastic spring, where the motor drives the load through the spring. The orientation of the shaft of the motor and the load are measured by position sensors. Position signals from the position sensors are sent to an embedded processor that determines the orientation of the load relative to the motor shaft to determine the torque on the spring. The embedded processor receives reference torque signals from a remote controller, and the embedded processor operates a high-speed servo loop about the desired joint torque. The remote controller determines the desired joint torque based on higher order objectives by their impedance or positioning objectives.