Time Optimal Motion Planning with ZMP Stability Constraint for Timber Manipulation

This paper presents a dynamic stability-constrained optimal motion planning algorithm developed for a timber harvesting machine working on rough terrain. First, the kinematics model of the machine, and the Zero Moment Point (ZMP) stability measure is presented. Then, an approach to simplify the model to gain insight and achieve a fast solution of the optimization problem is introduced. The performance and computation time of the motion plan obtained with the simplified model is compared against that obtained with the full kinematics model of the machine with the help of MATLAB simulations. The results demonstrate feasibility of fast motion planning while satisfying the dynamic stability constraint.