Direct digital design of computed torque controllers

Abstract

Direct digital design of computed torque controllers for a robot manipulator is discussed in this article. A simple discrete‐time model of the robot manipulator obtained by Euler's method is used for the design. Taking account of computation delay in the digital processor, we propose predictor‐based designs of the PD and PID type controllers. The PID‐type controller is designed based on a modified version of the discrete‐time integral controller proposed by Mita. For both controllers, the feedback gains can be determined easily by using simple formulas. A simulation example is presented to illustrate the relevance of the proposed designs and the robustness of PID‐type controller against physical parameter variations. © 1994 John Wiley & Sons, Inc.

Design and implementation of haptic interactions

“…Although the Newton-Euler equations have been traditionally used to model the system dynamics, Lagrange multipliers need to be employed in these models to handle constraints [57]. On the other hand, Kane's method [39] handles nonholonomic and changing constraints better because the equations of motion are expressed in terms of independent coordinates. Dependent coordinates can be obtained by integrating the constraint equations or solving the position problem.…”

“…Kane [39] as "It enables one to deal directly with nonholonomic systems without having to introduce and subsequently eliminate Lagrange multipliers".…”