Solid modelling of electrical wires on a computer graphics display screen

For some time now Heriot-Watt University has been helping Ferranti plc of Edinburgh to investigate the use of solid models in the production of assembly planning drawings. While the solid modelling of mechanical parts has been relatively successful, the representation of electrical wires has been a problem. This paper examines how electrical wires can be represented on a computer graphics display screen. In the first instance, a 'spline offset' program was written to draw wires in 2D. This approach is quite adequate for simple applications, but for more complex applications a second phase was undertaken whereby a 'solid modelling' program was written to create wires in 3D. The latter program is of particular interest because it can be used graphically to create curvy wires around an assembly of solid models representing mechanical parts; it also calculates the length, volume and weight of each wire created. © 1987.