A review of computer simulation of a low-order adaptive system based on curvature sensing and a bimorph mirror is given. The system was designed to accurately follow the lowest order Karhunen Loeve modes of the atmosphere. The purpose of the simulation was system design improvement and the determination of system performance limits. The four main areas of the simulation are described; atmospheric simulation, Fresnel propagation, bimorph model, and sensor feedback model. Results are presented and discussed.