Synthesis of velocity reference cam functions for smooth operation of high speed mechanisms

The purpose of the paper is to improve the dynamic performance of a mechanism used in a packaging machine in order to run the system at higher speeds with lower vibration and noise levels. A method of synthesising a velocity demand signal as a function of crank position (i.e. cam function) is demonstrated for a prototype mechanism and drive system. The method aims to minimise the peak to peak actuation torque requirements in order to minimise the vibration of the mechanism. First of all, experimental results are utilised to identify the drive system parameters. A dynamic simulation package is used to model the nonlinear dynamics of the mechanism. The model based synthesis of velocity reference cam functions is performed at increasing mechanism actuation speeds. The performance of the system using the proposed velocity demand cam function is compared with the conventional constant speed reference case at different running speeds.