A comparison of two methods for choosing repeatable control strategies for kinematically redundant manipulators Roberts, Rodney G. ; Maciejewski, Anthony A. "This work was supported by Sandia National Laboratories under contract number I8-4379B. Additional support was provided by the NEC Corporation and the TRW Foundation." A kinematically redundant manipulator is a robotic system that has more than the minimum number of degrees of freedom that are required for a specified task. Due to this additional freedom, control strategies may yield solutions which are not repeatable in the sense that the manipulator may not return to its initial joint configuration for closed end effector paths. This paper presents two methods for choosing repeatable control strategies which minimize their distance from a non-repeatable inverse with desirable properties. The first method minimizes the integral norm of the difference of the desired inverse and a repeatable inverse. While this is the more appropriate criterion, it results in a difficult optimization. The second method, which minimizes the distance of the null vectors associated with the desired and the repeatable inverses, is somewhat easier to implement. As an illustrative example the pseudoinverse is approximated in a region of the joint space using both techniques. Colorado State University. Libraries 1992 text ; image application/pdf ECEaam00064.pdf FACFECEN100064ARTI eng c1992 IEEE
A comparison of two methods for choosing repeatable control strategies for kinematically redundant manipulators
Roberts, Rodney G. ; Maciejewski, Anthony A.
"This work was supported by Sandia National Laboratories under contract number I8-4379B. Additional support was provided by the NEC Corporation and the TRW Foundation."
A kinematically redundant manipulator is a robotic system that has more than the minimum number of degrees of freedom that are required for a specified task. Due to this additional freedom, control strategies may yield solutions which are not repeatable in the sense that the manipulator may not return to its initial joint configuration for closed end effector paths. This paper presents two methods for choosing repeatable control strategies which minimize their distance from a non-repeatable inverse with desirable properties. The first method minimizes the integral norm of the difference of the desired inverse and a repeatable inverse. While this is the more appropriate criterion, it results in a difficult optimization. The second method, which minimizes the distance of the null vectors associated with the desired and the repeatable inverses, is somewhat easier to implement. As an illustrative example the pseudoinverse is approximated in a region of the joint space using both techniques.
Colorado State University. Libraries
1992
text ; image
application/pdf
ECEaam00064.pdf
FACFECEN100064ARTI
eng
c1992 IEEE