Investigation on Walking and Pacing Stability of German Shepherd Dog for Different Locomotion Speeds

The motion of three German Shepherd Dogs on a treadmill was recorded using a three-dimensional motion capture system. The locomotion speed of the dog was respectively set at 4 km·h−1, 5.5 km·h−1, 7 km·h−1 and 8.5 km·h−1. By processing the acquired data, the joint trajectories of the dogs' hind limbs were computed and a time series analysis was conducted. Joint angle-angle diagrams were obtained and the Lyapunov exponents were computed. Results show that the stability decreased when speed increased, which can be attributed to the decrease in the stance phase respect to the swing phase when speed is increased. Results also show that the dogs changed gait during the tests, namely walking in the range of 4 km·h−1 to 7 km·h−1 and pacing at 8.5 km·h−1. A significant drop in stability was observed from walking to pacing.