Abstract
Most studies of gait control focus phase difference control of limbs using a homogeneous model to realize various gait patterns.However, most animals including Thoroughbred horses have different natural frequencies in fore- and hindlimbs. Therefore, in order to achieve locomotion, frequencies of limb movement must be controlled so that they are kept constant. The aim of this study was to clarify frequency control mechanisms in equine limbs during swing phase. In this study, we measured limbs movements of 4 Thoroughbred horses cantering on the treadmill. An energy-based analysis was carried out using variable moment pendulum model. In hindlimbs, the energy source for swing is mainly the torque of rotation axis. On the other hand, forelimbs motion is caused by the pendulum extension/contraction in addition to the torque. Our results show that Thoroughbred horses choose appropriate energy generating strategy properly so as to compensate for asymmetry between fore- and hindlimb dynamics.
