Comparison of Linear and Torsion-Based Dynamic Modeling of a Jumping Robot via Energy Conversion

Dynamic modeling is very important for estimating the movements and forces of a robot. The model is used for detailed design of the kinematic and actuator parameters and for the synthesis of a controller. An incorrect model results in poor performance or unstable operation of the robots. A jumping robot is generally modeled by switching systems for before and after jumping, and a precise model is necessary to perform effective jumping. This paper analyzes two dynamic modeling methods for a jumping robot via the energy conversion principle. The robot uses a compliant link to jump by storing kinetic energy as potential energy in elastic deflection. Linear and torsion-based dynamic models were developed, and the torsion-based model uses a pseudo-rigid-body model. The modeling results were verified by simulation and experiment, and the results shows that the simple linear model is more suitable for estimating the movement. The model can be used to determine the optimal design parameters for effective and energy-efficient jumping.