T-FLoW 4.0 Biped Kinematics Computation Using Pseudoinverse and Orthogonal Rotational Matrix

A full kinematics analysis that considers both position and orientation is necessary to produce motion in humanoid robots, specifically for walking trajectory. The orientation analysis is often left out of publications when dealing with kinematics model. Therefore, this study provides full kinematics analysis both forward and inverse of bipedal system of our newest FLoW humanoid robot, T-FLoW 4.0. For the study of forward kinematics, Denavit-Hartenberg (DH) notation is used. While for inverse kinematics, we use pseudoinverse with the Jacobian method to solve the positions of the end effector and an orthogonal rotational matrix to solve the rotation one. Following that, an actual biped robot and Coppeliasim simulator were used to implement the algorithm. The outcomes demonstrate that using our kinematics model, the end effector could follow the specified trajectory with an average joint error equal to 0.05 degree and an average kinematics’s calculation time of 1 ms, which is sufficient for walking motion.