OPTIMUM DESIGN OF HIGH-SPEED FLEXIBLE ROBOTIC ARMS WITH DYNAMIC BEHAVIOR CONSTRAINTS

A methodology is presented for the optimum design of robotic arms unde r time-dependent stress and displacement constraints by using mathemat ical programming. Finite elements are used in the modeling of the flex ible links. The design variables are the cross-sectional dimensions of the elements. The time dependence of the constraints is removed throu gh the use of equivalent constraints based on the most critical constr aints. It is shown that this approach yields a better design than usin g equivalent constraints obtained by the Kresselmeier-Steinhauser func tion. An optimizer based on sequential quadratic programming is used a nd the design sensitivities are evaluated by overall finite difference s. The dynamical equations contain the nonlinear interactions between the rigid and elastic degrees-of-freedom, To illustrate the procedure, a planar robotic arm is optimized for a particular deployment motion by using different equivalent constraints. (C) 1997 Elsevier Science L td.