This paper describes the prototype assembly planner, which derives the
optimal assembly sequence from a product's specification. Assembly re
presentation used as an input to the planner is based on spatial relat
ionships between parts, which are directly related to the geometry of
the assembly move. This way, in addition to the input specification of
the product, they can be used for output specification of the necessa
ry assembly moves. The space of all possible assembly sequences is rep
resented by an AND/OR graph. The graph is searched for the best sequen
ce using the variant of the AO heuristic algorithm. The output of the
system is the optimal assembly sequence with a description of the req
uired assembly moves. The assembly sequence is, at this stage, evaluat
ed with respect to geometrical feasibility, stability, and parallelism
. To cope with the complexity of the implemented approach, we develope
d efficient algorithms for generating and searching the problem space.
Empirical evaluation shows the ability of the system to deal with rea
l-world assemblies.