Analysis of the dynamics of a slider-crank mechanism locally actuated with an act-and-wait controller

Traditional use of slider-crank mechanisms result in high loads transmitted through the mechanical structure, inhibiting the design of a compact machine. Therefore, this paper proposes to step away from the conventional, i.e. rotative, actuation and to investigate local linear actuation of the slider-component directly, while maintaining the kinematic link. In this work the equation of motion and corresponding non-isochronous movement are derived for the proposed system, loaded with a linear spring-damper element. Afterwards the focus shifts towards the evaluation of the local linear actuating principle by implementing an act-and-wait control strategy in a multibody model in Simscape. The obtained configuration results both in a continuous movement of the slider mechanism where Top Dead Centre & Bottom Dead Centre are reached and in a minimisation of the loads transmitted through the mechanical structure. Further investigation of one of the most determining parameters, i.e. the operating frequency, proves that operating at the resonance frequency of the system, yields optimal results. This configuration allows for the reduction of the loads transmitted through the system by 90% of the nominal spring-damper load.