A horseback riding simulator is developed to overcome challenges occurring on real horses. The goal of the simulator is to provide a real horseback riding-like sensation to the user in various situations with limited workspace. This paper focuses on generating various trajectories at different walking speeds with dynamic effects. A walking horse dynamic model is purposed based on a two-linked rimless wheel and is modified with 3D-captured data from a real horse. A controller is also designed for passing and compression-recoil modes, aiding in changing the models walking speed using speed change input. A dynamics simulation is performed and results show that the suggested walking model covers trajectory with measured data and shows more variation.