Inverse dynamics calculation of underactuated link systems using parallel solution scheme

A general-purpose solution scheme of inverse dynamics for link systems was developed on the basis of a finite element approach. It can not only deal with different types of configurations, such as open-loop, closed-loop, or multibranch link systems, but also with the elasticity of constituted links without the need to revise any part of the scheme. The main objective of this study is to extend the use of the scheme by applying the inverse dynamics calculations to several types of underactuated link systems. A solution scheme of kinematics is also developed on the basis of the finite element method in order to calculate target trajectories that compensate for the inertial forces acting in the systems. The obtained trajectories are fed into the inverse dynamics calculation using the parallel solution scheme. The torque values are verified through comparison with the input moment used in finite element analyses, and the validity of the parallel solution scheme is confirmed.