Utilisation of an accelerometric device in equine gait analysis

Summary An accelerometric device was developed for evaluating the gait of young horses in field situations. Some measurements and data analysis were made to show its potential applications in gait analysis. The transducers consisted of two accelerometers measuring acceleration along the longitudinal and dorso-ventral axes of the horses. They were put into a leather pocket applied over the sternum by means of an elastic girth fastened onto the horse. This accelerometric belt was connected to a light weight radio telemetric system. The signals were transmitted to a receiver connected to a portable microcomputer. An alternative method to use this device was to connect it directly to an analog-digital converter of the microcomputer. The maximum data acquisition rate was 50 Hz for each accelerometer using the telemetric system and 3500 Hz using direct connection. The accelerometric device could be used either on a treadmill or in field situations. Longitudinal and dorsoventral acceleration of the sternum provided some information about basic temporal stride kinematics and kinetics of a running horse. Two tests illustrated the usefulness of the accelerometric belt to investigate the velocity-dependent changes in stride frequency and longitudinal acceleration, and the gait asymmetry of a lame horse. Three signal analysis procedures were used for data analysis, respectively: Fourier analysis, peak-finding and autocorrelation functions. It was concluded that the accelerometric belt allows an objective study of some basic characteristics of the horse locomotion in field situations. It could be useful to test young horses provided that standardised protocols are developed to measure and analyse the acceleration data.