According to clinical experiences, the therapist must accompany patients to monitor and guide them to walk in a correct gait pattern while receiving training. Otherwise the patients may build a wrong stepping habit, and in the long run may cause secondary injury. However, due to limited man power, therapists are not always available and the patients do not receive enough trainings. Thus the patients recover slowly to a limited extend. In order for walking disabled patients to recover quickly to their highest level in correct way, we previously developed two kinds of visual cue devices. One is walker combined with visual cue to improve Parkinson disease patients' walking performance, and the other is quadricane/cane with visual cue to help hemiplegia stroke patients. Although our studies show these devices do improve users' performance, there are still some problems while visual cue attached on assistive devices. For example, users need to coordinate the device rather than their own walking habit and ability, the devices may be limited by the environment outdoor or even indoor. Therefore we further develop a body-worn visual cue device in this study. The purpose of this paper is to develop the experiment protocols to evaluate the functionality of the latest version device for future clinical applications. In the simulate experiment, we get the preliminary result that the procedure is feasible, and the parameters are confirmed.