Figure 2.

Stride force (Θ, dark grey), velocity (Λ, light grey) and collision (Φ, unfilled regions) angles for all three gaits of dogs (D) and goats (G) were determined according to the equations of table 1. (A planar representation of instantaneous collision angles is provided for reference.) Vertical lines indicate 95% confidence intervals of each angle. Collision fraction is given by Φ/Λ + Θ, representing the actual/potential collision. Smaller collision fractions indicate more collision reduction. All angles are steady speed values predicted by the generalized linear model at an impulse angle of zero (no net horizontal acceleration of the CoM). Mean forward velocities of each gait, normalized according to equation 1, were 0.62 (walk), 1.42 (trot) and 2.72 (gallop).