Dual Execution of Optimized Contact Interaction Trajectories


Conference Paper



Efficient manipulation requires contact to reduce uncertainty. The manipulation literature refers to this as funneling: a methodology for increasing reliability and robustness by leveraging haptic feedback and control of environmental interaction. However, there is a fundamental gap between traditional approaches to trajectory optimization and this concept of robustness by funneling: traditional trajectory optimizers do not discover force feedback strategies. From a POMDP perspective, these behaviors could be regarded as explicit obser- vation actions planned to sufficiently reduce uncertainty thereby enabling a task. While we are sympathetic to the full POMDP view, solving full continuous-space POMDPs in high-dimensions is hard. In this paper, we propose an alternative approach in which trajectory optimization objectives are augmented with new terms that reward uncertainty reduction through contacts, explicitly promoting funneling. This augmentation shifts the responsibility of robustness toward the actual execution of the optimized trajectories. Directly tracing trajectories through configuration space would lose all robustnessâ??dual execution achieves robustness by devising force controllers to reproduce the temporal interaction profile encoded in the dual solution of the optimization problem. This work introduces dual execution in depth and analyze its performance through robustness experiments in both simulation and on a real-world robotic platform.

Author(s): Toussaint, M. and Ratliff, N. and Bohg, J. and Righetti, L. and Englert, P. and Schaal, S.
Book Title: Proceedings of the International Conference on Intelligent Robots and Systems
Year: 2014
Month: October

Department(s): Autonomous Motion, Movement Generation and Control
Research Project(s): Interactive Perception
Bibtex Type: Conference Paper (inproceedings)
Paper Type: Conference

Address: Chicago, IL
DOI: http://dx.doi.org/10.1109/IROS.2014.6942539

Links: PDF


  title = {Dual Execution of Optimized Contact Interaction Trajectories},
  author = {Toussaint, M. and Ratliff, N. and Bohg, J. and Righetti, L. and Englert, P. and Schaal, S.},
  booktitle = {Proceedings of the International Conference on Intelligent Robots and Systems},
  address = {Chicago, IL},
  month = oct,
  year = {2014},
  month_numeric = {10}