Recent efforts in computer aided design and computer aided manufacturing have stressed the development of robotics. However, there are many applications where a spatial mechanism could be used in place of a robot, but the mechanism design theory has not been fully developed. This thesis presents the fundamentals of a computer aided design system for the RSCR (revolute-spheric-cylindric-revolute) spatial mechanism. Exact relationships for position, velocity, and acceleration analysis have been derived. Closed form synthesis equations have been developed for the RS and RC dyads. The theory developed in this thesis has been implemented on the digital computer in the form of a FORTRAN77 computer program. This computer implementation includes interfaces with MECHIN, a graphical preprocessor for spatial mechanism synthesis and analysis, and GENMOD, an automatic model generator for spatial mechanisms. / Master of Science