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Combined Task and Motion Planningfor Mobile Manipulation

Jason Wolfe, etc.University of California,

Berkeley

Mozi SongINFOTECH

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Layout

• Problem introduction• Domain and Hierarchy• SATHN algorithm• Results• Conclusion

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Layout

• Problem introduction• Domain and Hierarchy• SATHN algorithm• Results• Conclusion

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Introduction:1. Pick-and-Place problem

•Abstract actions•Primitive actions

Action Hierarchy

Action levels

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Introduction: 2. Tasks

•Sequence operations•Decide on details•Optimize

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Introduction:3. Challenges

• Geometric constraints• Real-time limits

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Layout

• Problem introduction• Domain and Hierarchy• SATHN algorithm• Results• Conclusion

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Domain and Hierarchy1. Initial state

• Robot configuration• Object geometry, position,

relation with other objects

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Domain and Hierarchy2. Transition model

*external planners instead of PDDL—dealing with uncertainty

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Domain and Hierarchy3. Action hierarchy

• High-level-actions(HLA)• Immediate refinements

of each HLA

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Domain and Hierarchy3. Action hierarchy

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Domain and Hierarchy3. Action hierarchy

• Infinite refinements of an HLA:

random sampled sequence

• Hierarchically optimal result

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Layout

• Problem introduction• Domain and Hierarchy• SATHN algorithm• Results• Conclusion

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SATHN Algorithm

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SATHN Algorithm

subtask-specific irrelevance

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Layout

• Problem introduction• Domain and Hierarchy• SATHN algorithm• Results• Conclusion

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Results

• Feasibility• Efficiency

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Layout

• Problem introduction• Domain and Hierarchy• SATHN algorithm• Results• Conclusion

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Conclusion

• Action hierarchy• State abstraction• A proof-of-concept of task-level planning

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Conclusion-Future work

• Approximate models for the HLAs and primitives

• Search algorithms managing cost-quality tradeoff

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Q & A

• Problem introduction• Domain and Hierarchy• SATHN algorithm• Results• Conclusion

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Thank you