A device independent system is described for the visualization, modeling, and animation of spatial mechanisms and robots. New ideas and methods are presented to simplify the interactive specification of scene rendering and color parameters using the ISO standard for 3-D graphics, the Programmer’s Hierarchical Interactive Graphic System (PHIGS) and its extensions PHIGS+.
The parallels between the PHIGS hierarchical structure and spatial mechanism modeling are described from the level of mechanism through links, joints, geometry primitives to PHIGS graphics primitives.
Perception and evaluation of spatial mechanism designs are significantly improved by the use of shaded, lighted, depth cued models under animation. The method is coupled to new algorithms for automatic interference detection and reshaping of mechanism links to avoid collisions.
The suitability of PHIGS+ for the modeling and simulation of open loop mechanisms is also described. Examples are presented for rendering and animation of spatial mechanisms on a Raster Technologies (Alliant) GX4000 workstation with a hardware based PHIGS+ graphics subsystem, UNIX, NeWS, and C.