'StCAD' is capable of full 3D pan, zoom, tilt and rotate. Available solids are extrusions of rectangles, circles, ellipses and polygons. The solids can be positioned and oriented exactly in space, as are markers on the solids. Exact specification of linear and angular velocities of solids in space are also possible. Mass and inertia properties can be user specified or automatically computed based on uniform density. Available joints are spherical (ball), revolute (pin), translational (slider), cylindrical, planar, fixed, universal, point in line, point in plane, parallel, perpendicular, no rotation, constant velocity, rack pinion, screw. The curve-curve contact allows liftoffs and collisions based on coefficient of restitution. Available actuators are rotary and translational. Their motions are user prescribed functions of time. Forces and torques are user prescribed functions of time, displacements and velocities in all three components or along connecting markers. Example formulas for spring, damper, bushing, beam, aerodynamic, inverse square law and other forces and torques are given. Available functions are sqrt, exp, ln, lg, sin, cos, tan, arctan, arctan2, spline, spectral density. Users can specify constant gravity of arbitrary magnitude and direction.
Users need to provide the domain to simulate the behavior of the system. Simulation progress can be animated and stopped any time. After simulation, the computed solution can be used for animation or frame by frame analysis. Full 3D pan, zoom, tilt and rotate is available during simulation and animation. Users can also obtain output data in the form of plots and tables. XY plots can be zoomed and set to equal scales. Individual parts can be saved into files and reinserted into any assembly repeatedly. Assemblies can be saved in binary or tab delimited text format with textual notes and simulation data for later reload. The text format allows pre and post processing of assemblies by other programs, especially spreadsheet programs. Other specific text formats are for MOSES, PDMS Review and POV-Ray. 'StCAD' runs on Windows, Macintosh PPC, Linux PC and other Unix's. Assembly data are unchanged across platforms.