Flexible Robot Collision Dynamics Modeling And Simulation

New technologies are leading the development of robots to the trend of high speed and precision, light weight and large scale, which give rise to problems of flexibility and cooperation between a robot and its manipulating objects or between multiple robots. Since problems of impact are frequently encountered in robotics, the impact dynamics of flexible robots is currently one of the most intriguing subjects both in the robotics and multi-body dynamics fields. This dissertation discusses the impact dynamics of a flexible robot colliding with its working environments, which is helpful for the dynamic simulation and control of flexible robots. The system considered here is a robot consisting of n slender flexible-links which are connected by rotary joints. The kinematics of the system is described by 4 × 4 homogeneous transformation matrices and the approach of assumed modes is used to describe the link deflection. By introducing the concept of impulse potential energy, the generalized impulse-momentum equation is developed which describes the dynamics of a flexible robot with external impacts. Environments can be the ground, moving or static objects, even another robot, and so on. In this paper we consider another robot as environment for generality. Any other cases can be included in it via specifying a few parameters. The dynamic responses of the two colliding mono-arm robots and two colliding multi-arm robots are obtained in the form of generalized impulse-momentum equation with the help of equations involving coefficient of restitution. The resulting equations are not coupled and written in scalar form and 4X4 matrix operations ready for computer programming. In order to validate the method presented in this dissertation, several examples are simulated and analyzed in the end.