Dynamical model of ball juggling Delta robots using reflection laws

Abstract

In this paper, the dynamical model of the ball juggling robot is presented. The dynamical model takes advantage of the fact that instead of using the camera or vision system, this dynamical model can be used to continuously calculate ball velocity and position during juggling or playing between two robots. In ball juggling or playing robot experiments the most difficult task is to get the position and velocity of the ball during play. This paper deals with calculating the position and velocity of the ball continuously during juggling or playing with the rigid racket. Basic physics reflection laws are used to calculate the outgoing velocity of the ball after each hit. The hitting of the ball on the racket is detected by measuring the distance between the ball contact point and the rigid racket surface. To get the velocity and position of the ball throughout the juggling, the gravitational effect is also incorporated. An overall structure of the stand alone model is also proposed to get the position and velocity continuously. This model is computationally less expensive and gives better insight of the juggling. To validate this dynamical model, experiments are performed on the test bench. The results of this dynamical model are compared and analysed with the results obtained from the RecurDyn simulation and test bench experiment.