Time-Optimal Trajectory Planning with Interaction with the Environment

TL;DR

This paper introduces a method for time-optimal trajectory planning that incorporates external wrenches exerted during environmental interactions, validated through real robot experiments under admittance control.

Contribution

It presents a novel strategy to include external interaction forces in optimal motion planning, addressing a gap in existing methods that neglect environmental wrenches.

Findings

Including external wrenches alters the planned trajectory.

The method improves dynamic capability considerations in planning.

Validated on a real robot performing an interaction task.

Abstract

Optimal motion planning along prescribed paths can be solved with several techniques, but most of them do not take into account the wrenches exerted by the end-effector when in contact with the environment. When a dynamic model of the environment is not available, no consolidated methodology exists to consider the effect of the interaction. Regardless of the specific performance index to optimize, this article proposes a strategy to include external wrenches in the optimal planning algorithm, considering the task specifications. This procedure is instantiated for minimum-time trajectories and validated on a real robot performing an interaction task under admittance control. The results prove that the inclusion of end-effector wrenches affect the planned trajectory, in fact modifying the manipulator's dynamic capability.