Abstract: Symbolic computing can facilitate the application of modem nontinear system anatysis and design methods to engineering problems. Reasonably complex models can be efficiently assembled and manipulated. In this paper we illustrate the symbolic constnrction and manipulation of a model of an undersea vehicle. While the system cmrsidered here is within the reafm of hand assembly, doing so is tedious and error prone. On theotherhand,itis trivial withthesymboliccomputingtoolsdescribedhere.More complex, multitmd y configurations ofunderseavehiclesandrobotscanbe dealtwith usingthesetechniques.