An early design for a leg mechanism called the "Plantigrade Machine" by Pafnuty Chebyshev was shown at the Exposition Universelle (1878). The original engravings for this leg mechanism are available. The design of the leg mechanism for the Ohio State Adaptive Suspension Vehicle (ASV) is presented in the 1988 book "Machines that Walk". In 1996, W-B. Shieh presented a design methodology for leg mechanisms.