Optimal joint trajectory planning for a robot with elastic links

The optimal joint angle trajectory planning of light-weight flexible manipulator is investigated based on the cycloidal motions of each joint. The objective of the optimization is the minimization of link tip vibrations during and after joint motion, and the design variables are the inflection or switch point of the cycloidal motion; The Lagrangian equations are used to derive the dynamic equations of motion and the Assumed-modes method is used for numerical solution. The proposed optimum joint angle trajectory can be implemented by off-line programming for the minimum vibration of robot arms; One and two flexible links cases are investigated and computer simulation is performed for different payloads and manipulator configurations

Modelling and Validation of Robot Manipulators

There are many methods to describe manipulator dynamics, the iterative Newton-Euler dynamic formulation and the Lagrange-Euler formulation are two of them. Between these two well known methods, the former has been regarded as computationally efficient, and the latter as understandable in representing manipulator dynamics. It is hard and dull to generate robot manipulator dynamic equations manually from either the iterative Newton-Euler dynamic formulation or the Lagrange-Euler formulation. Therefore, the two general programmes, which are based on these two formulations respectively and suited to rotary joint manipulators, have been written in REDUCE. After running the programmes, we find that the calculation time for generating the dynamic equations of a rotary joint manipulator by the programme based on the Lagrange-Euler formulation is much shorter than the one by the programme based on the other

Dynamic modelling of flexible robot manipulators

The problem of modeling flexible robots is considered. The dynamic model is obtained by using a generalized Lagrangian approach and by expanding in a limited number of terms the function describing the exact shape of bent beams constituting the robot. General properties of the model, such as controllability, are then investigated. To manipulate the cumbersome formulas the SAM language MACSYMA has been extensively used