LSPB trajectory planning and PD joint control for a 6-DOF manipulator, with torque estimation validated through motor current profiling.
This project implements full joint-space trajectory control and dynamics analysis for the OpenManipulator X, a 6-DOF serial manipulator arm. The work covers both trajectory planning and torque-level dynamics validation.
LSPB Trajectory Planning: Linear Segment with Parabolic Blends (LSPB) profiles were used for smooth joint-space motion. The planner produces position, velocity, and acceleration profiles that respect joint limits while minimizing jerk at transition points.
PD Joint Control: Independent PD controllers are implemented per joint. Gains were tuned using Ziegler–Nichols initial estimates followed by fine-tuning against step and trajectory responses.
Torque Estimation & Wrench Analysis: The Euler–Lagrange dynamic model was used to compute expected joint torques along planned trajectories. These were compared against torque estimates derived from motor current profiles, validating the dynamic model.
The LSPB+PD system achieved under 5% path tracking error across all tested trajectories. Torque estimates from the dynamic model matched motor-current-derived measurements within approximately 5%, validating the modeled dynamics.