Lab Papers (GRASP)

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Conference Paper

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Copyright 2009 IEEE. Reprinted from:
Vernaza, P.; Likhachev, M.; Bhattacharya, S.; Chitta, S.; Kushleyev, A.; Lee, D.D., "Search-based planning for a legged robot over rough terrain," Robotics and Automation, 2009. ICRA '09. IEEE International Conference on , vol., no., pp.2380-2387, 12-17 May 2009

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We present a search-based planning approach for controlling a quadrupedal robot over rough terrain. Given a start and goal position, we consider the problem of generating a complete joint trajectory that will result in the legged robot successfully moving from the start to the goal. We decompose the problem into two main phases: an initial global planning phase, which results in a footstep trajectory; and an execution phase, which dynamically generates a joint trajectory to best execute the footstep trajectory. We show how R* search can be employed to generate high-quality global plans in the high-dimensional space of footstep trajectories. Results show that the global plans coupled with the joint controller result in a system robust enough to deal with a variety of terrains.


legged locomotion, path planning, position control, complete joint trajectory, footstep trajectory, legged robot, rough terrain, search-based planning, search-based planning approach



Date Posted: 01 October 2009