Determining power consumption using neural model in multibody systems with clearance and flexible joints

Abstract

Even if today’s manufacturing technology has great advances, clearance between joint parts in a multibody system is inevitable due to the assemblage and relative motion of neighbour links. If a joint has excessive clearance size, it leads to negative effects on the system performance and unforeseeable power consumption occurs during the life-cycle of a mechanical system. Instant change at the electric current makes the actuator lifetime shorter. In this study, actuator current fluctuation and power consumption in the spatial multibody system are investigated. Classic and compliant slider-crank mechanisms with clearance and flexible joints are studied together. Hertz contact theory comprising the model of Lankarani and Nikravesh is considered to comment on the joint forces on the power consumption. Coulomb’s friction law is preferred to evaluate the friction behaviours. A dynamic neural predictor is also designed to determine the current fluctuation for the different working parameters. Experimental data is used for the prediction stability of the neural model. The results outline that the clearance joint has a dominant effect on the power consumption and the current fluctuation of the actuator. The designed neural predictor has stable and superior performances to predict and estimate the current fluctuation. In the design stage of the system, therefore, researchers can judge the power consumption of similar mechanical systems having imperfect joints and may select the suitable actuator for real working conditions.