Gait pattern and energetic cost in hexapods

Legged animals change their gait pattern, such as walk, trot, and gallop, according to locomotion speed, which suggests that optimal gait pattern is selected so as to minimize the energetic cost of locomotion. The author examined the relationship between gait pattern and the energetic cost which is given by positive work and heat energy loss caused by viscosity and joint torque in a dynamical model of a hexapod. The author reports the results and show that crucial characteristics in locomotor patterns of legged animals are the result of optimization based on energetic efficiency, such as the phase transition between typical gait patterns, the constancy of metabolic cost to move unit distance, and so on.