The design of these four-legged walkers relies on Curvature theory to find a flat-sided coupler curve of a four-bar linkage to be used for the foot trajectory. This coupler curve is repositioned using a skew pantograph. The result is a six-bar leg mechanism.
Stable gait for these walkers can be achieved by adding side-to-side foot extensions to broaden the support polygon during walking.
Please see this video showing walkers designed by my students to be a rabbit, two dogs, a bear, a rhinoceros, a dinosaur, and a centaur, as well as a legged platform, a legged syringe and the Star Wars All-Terrain Attack Transport, known as AT-AT.