Version 1.0, August 31, 2001, Copyright, Hugh Jack 1993-2001
Generalized cones [R.A.Brooks, 1983] are a faster approach than the Cartesian Configuration Space method . These cones are achieved through a special representation of the environment. The surfaces of convex polygons are used to determine conically bounded pathways, for the path of the object being moved. The method of determining free pathways (or Freeways) is based on the use of cone shaped spaces. The cones fit snugly between objects and have spines that run along the centre of the cones. These spines are the paths that the object may travel along. This makes the method inherently 2D and thus has not been implemented in 3D as of yet, but it has spawned a method which is successful in 3D by Brooks[1983]. To determine which spines to follow, the author uses the A* search technique to explore the various paths along the spines. This leads to problems in cluttered spaces where certain possible paths may be overlooked by the generalized cones. This method chooses a path with considerable clearance of objects.
Figure B.3 Problem Represented with Generalized Cones
Figure B.4 Problem Represented with Generalized Cones
As can be seen the rotation with this technique is very restricted, and the object is typically oriented with the spine.