New Results on Robot Modeling and Simulation

In this paper the possibility of simulating the robot forward dynamics by making use of the inertia matrix and of the kinetic energy gradient only is demonstrated. Such method is shown to be simpler and numerically more efficient than the classical approaches. In the case of planar robots with revolute joints and link centers of mass belonging to the plane containing the rotating axes of the joints, theorems are formulated and demonstrated providing a relatively fast and simple method of calculation for both the inertia matrix and the gradient of the kinetic energy. This allows obtaining a simple and efficient tool to simulate practical robots with rigid links and can also be particularly useful for studying robots with flexible links. By using the proposed approach, the model of a practical planar robot, designed by the computer aided design software package CATIA™, is easily developed and implemented. The simulation results when the gradient of the kinetic energy is computed analytically versus numerically are compared to illustrate that the computational costs are relatively low and the accuracy is high.