Constraint-based Task Specification and Trajectory Optimization for Sequential Manipulation

TL;DR

This paper introduces a constraint-based method for specifying sequential manipulation tasks and computing time-optimal robot motions, enabling efficient and intuitive programming across diverse robot models.

Contribution

It presents a novel, object-centric, constraint-based task specification approach that transforms into a non-linear optimization problem for time-optimal sequence planning.

Findings

Successfully applied to five different robot models

Achieved near-optimal motion sequences in experiments

Demonstrated effectiveness on a highly redundant mobile manipulator

Abstract

To economically deploy robotic manipulators the programming and execution of robot motions must be swift. To this end, we propose a novel, constraint-based method to intuitively specify sequential manipulation tasks and to compute time-optimal robot motions for such a task specification. Our approach follows the ideas of constraint-based task specification by aiming for a minimal and object-centric task description that is largely independent of the underlying robot kinematics. We transform this task description into a non-linear optimization problem. By solving this problem we obtain a (locally) time-optimal robot motion, not just for a single motion, but for an entire manipulation sequence. We demonstrate the capabilities of our approach in a series of experiments involving five distinct robot models, including a highly redundant mobile manipulator.