Abstract
We constructed a two-dimensional musculoskeletal model of the Japanese macaque for simulation of bipedal walking based on forward dynamic simulation. The musculoskeletal system was constructed as 9 rigid links with 10 principal muscles. To generate locomotion, phase oscillators were used as a model of the spinal central pattern generator and motor commands sent to each muscle was modeled as a combination of square waves. By determining the parameters defining the shape of motor commands using genetic algorithm such as to maximize walking distance and to minimize energy expenditure, bipedal locomotion was generated. Although the generated walking pattern did not coincide with that of actually measured, we found that incorporating restricted joint motions due to muscle's passive resistive property is important for simulating monkey-like bent-hip, bent-knee bipedal walking.
