TY - JOUR
T1 - Online near time-optimal trajectory planning for industrial robots
AU - Kim, Joonyoung
AU - Croft, Elizabeth A.
PY - 2019/8/1
Y1 - 2019/8/1
N2 - A novel trajectory planning approach is presented suitable for online industrial robot applications along short path segments such as spot-welding. The proposed method generates trajectories that are computationally efficient, dynamically near time-optimal, and maintain path-following integrity in high-frequency planning-and-control cycles. The method is based on the well-known path constrained time-optimal motion. We show that this trajectory can be quickly approximated with trapezoidal velocity profiles, resulting in near time-optimal trajectories, requiring only four robot dynamics computations per path segment. For continuous motions, a method to safely transit between adjacent optimal path segments within geometric bounds is also presented. We then show how the generated second order trajectory can be successfully used with a generic control loop by adopting feedforward control based on an elastic model. A real-world experiment with a 6DOF industrial robot validates our approach.
AB - A novel trajectory planning approach is presented suitable for online industrial robot applications along short path segments such as spot-welding. The proposed method generates trajectories that are computationally efficient, dynamically near time-optimal, and maintain path-following integrity in high-frequency planning-and-control cycles. The method is based on the well-known path constrained time-optimal motion. We show that this trajectory can be quickly approximated with trapezoidal velocity profiles, resulting in near time-optimal trajectories, requiring only four robot dynamics computations per path segment. For continuous motions, a method to safely transit between adjacent optimal path segments within geometric bounds is also presented. We then show how the generated second order trajectory can be successfully used with a generic control loop by adopting feedforward control based on an elastic model. A real-world experiment with a 6DOF industrial robot validates our approach.
KW - Industrial robots
KW - Trajectory planning
UR - http://www.scopus.com/inward/record.url?scp=85062661204&partnerID=8YFLogxK
U2 - 10.1016/j.rcim.2019.02.009
DO - 10.1016/j.rcim.2019.02.009
M3 - Article
AN - SCOPUS:85062661204
SN - 0736-5845
VL - 58
SP - 158
EP - 171
JO - Robotics and Computer-Integrated Manufacturing
JF - Robotics and Computer-Integrated Manufacturing
ER -