It is important for cable assembly to simulate the process planning on mechanical and electrical products in virtual environments.The planar static cable model was proposed according to the theory of catenary for cables to install under the suspended condition.To satisfy the real-time requirement for the cable assembly simulation,the planar cable model could be built rapidly by the algorithm analysis on its key parameters on condition that the cable length and two fixed endpoints of the cable were determined.Using the coordinate transformation method,the 3D cable assembly simulation model under the suspended condition could be gotten from the planar cable model,which is suitable for the environment platform.Using the cable assembly simulation model,the dynamic simulation for cables under the suspended condition could be realized by real-time getting cable’s terminal point coordinates and computer screen’s refreshing.At the same time,the tensions of each key point of cables could be computed to guide cable realistic assembly process.

Auto-extracting of the constraint face information of parts is an important issue of virtual assembly.It presents a new approach of determining constraint faces of parts effectively,designs a new algorithm which may recognize constraint surfaces of parts and extracts automatically the constraint surfaces parameters.The example shows that the approach can meet the needs of assembly process planning and improve the efficiency of constraint recognition effectively.