# Smooth Orientation Trajectory Generator Respecting Kinematic Limits

Grassmann, Reinhard; Burgner-Kahrs, Jessica
IEEE-RAS International Conference on Humanoid Robots, 2019

## Abstract

Smooth position and orientation interpolation has a great effect on the performance of robot manipulators. Interpolation between several via positions can be done in a straightforward manner, which is well covered in the literature. However, generating a suitable trajectory between several orientations is still an open problem. In this letter, we introduce a novel trajectory generator capable of respecting kinematic limits. We address the problem of generating a singularity-free trajectory for multiple via poses in $\boldsymbol{S\;E(3)}$ , while complying with the requirement of $\boldsymbol{\mathcal {C}^4}$ continuity. To achieve this, a smooth trapezoidal-like velocity profile and unit quaternions are used. A simulation platform in V-Rep based on a 7-DOF lightweight robot, including inverse kinematics and dynamics is used to demonstrate the effectiveness of our trajectory generator.