CS 326 A: Assembly Planning

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CS 326 A Assembly Planning
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Range of Problems

• Parts are assumed free-flying Assembly
  sequence planning Example of multi-robot
  coordination (many dofs)
• Tools are taken into account
• The entire manipulation system is taken into
  account Manipulation planning (movable
  objects)

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Aspects of Assembly Sequence Planning

• The goal state assembled product -- is very
  constrained, while the initial state separated
  parts -- is not Disassembly planning
  (planning backward)
• The number of dofs is large, but disassembly
  paths are often simple Motion space
  (instead of configuration space)

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Applications

• Answers to questions such as
• How many parts need to be removed to extract a
  given part P?
• Can the product be assembled by adding a single
  part at a time?
• How much can the assembly processed by
  parallelized?
• Design for manufacturing and servicing
• Design of manufacturing systems

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Planning Approaches

• Generate-and-test
• Generate-and-test plus caching
• Non-directional blocking graph
• Interference diagram

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Example of Application of NDBG
472-part Hughes AIM-9X air-to-air missile

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Conclusions

• NDBG works well in practice, but for simple
  motions
• Interference diagrams are still not practical
• Dealing with tools and other manipulation devices
  (grippers, robot arms, fixtures) remains mostly
  an open problem
• Planning non-monotonic sequences has not been
  done so far