Aiming at the present gait instable walking-aid, a low cost walking-aid research platform is designed in this paper. The paper developed a dynamic walking aids mechanical design process which based on the study of body's gait stability and motion parameters, analyzed the structural design of the walking aids in ergonomic principles. Furthermore, based on the ZMP gait stability theory, adopting a composed design/integrated optimization gait planning method to program the gait of normal walkers and wearers. Adjusting the ankle joint to the rear foot and the trajectory of the hip’ abscissa is integrated to modify the actual ZMP trajectory to the ideal ZMP trajectory. The proposed composed design/integrated optimization method greatly simplifies the programming process and provides a good experiment platform for walking aid teaching and scientific research.