Dynamic behaviour of a SCARA robot with links subjected to different velocity trajectories
The dynamics of a mechanical manipulator have the inherent characteristics of being highly non-linear and strongly coupled due to the interaction of the inertial, centripetal, coriolis and gravitational forces. These characteristics produce difficulties in predicting the dynamic behaviour of a given manipulator's structure. These interactive forces depend largely on the geometrical configuration and operational conditions of a manipulator. Therefore, it is essential to investigate the dynamics behaviour under different conditions in order to obtain an optimal design. This paper presents a study of the dynamics behaviour of a robot's arm with particular reference to the mechanical manipulator being designed by the AEAC. A computer software package has been developed to facilitate the investigation of the potential dynamics behaviour of a robot's arm and provides the designer with useful information for the real time control of high performance robots. This package also enables the designer to closely monitor the implications of his design. The software of this package is based on the Lagrangian model, taking advantage of the recursive formulation. A brief description of the types of velocity trajectories used in this study is also included in this paper. The software for the modelling was written in FORTRAN 77 in single precision and run on a UNIVAC operating system.