An Algorithm for Planning Collision-Free
Paths Among Polyhedral Obstacles
This paper describes a collision avoidance algorithm
for planning a safe path for a polyhedral object moving among
known polyhedral objects.  The algorithm transforms the obstacles
so that they represent the locus of forbidden positions for an arbitrary
reference point on the moving object.  A trajectory of this
reference point which avoids all forbidden regions is free of collisions.
Trajectories are found by searching a network which indicates, for each vertex 
in the transformed obstacles, which other vertices can be reached safely.
CACM October, 1979
Lozano-Perez, T.
Wesley, M.A.
