Learning Configuration Space Belief Model from Collision Checks for Motion Planning

Sumit Kumar; Shushman Choudhary; Siddhartha Srinivasa

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arXiv · 1901.07646

Learning Configuration Space Belief Model from Collision Checks for Motion Planning

Sumit Kumar·Shushman Choudhary·Siddhartha Srinivasa

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Abstract

For motion planning in high dimensional configuration spaces, a significant computational bottleneck is collision detection. Our aim is to reduce the expected number of collision checks by creating a belief model of the configuration space using results from collision tests. We assume the robot's configuration space to be a continuous ambient space whereby neighbouring points tend to share the same collision state. This enables us to formulate a probabilistic model that assigns to unevaluated configurations a belief estimate of being collision-free. We have presented a detailed comparative analysis of various kNN methods and distance metrics used to evaluate C-space belief. We have also proposed a weighting matrix in C-space to improve the performance of kNN methods. Moreover, we have proposed a topological method that exploits the higher order structure of the C-space to generate a belief model. Our results indicate that our proposed topological method outperforms kNN methods by achieving higher model accuracy while being computationally efficient.

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BibTeX RIS

Sumit Kumar, Shushman Choudhary, Siddhartha Srinivasa. 2019-01-22. Learning Configuration Space Belief Model from Collision Checks for Motion Planning. https://arxiv.org/abs/1901.07646

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