In recent years, different types of commercial rollators or gait-training devices have been widely used by elderly people, suffering from dementia, for their daily activities to avoid being bedridden. However, the effectiveness of most of these commercial devices has not been investigated thoroughly. In this study, a novel rollator with a freely rotating chest pad, integrated with two angular sensors and two load cells, was developed. Walk measurements were carried out on four young healthy subjects who performed walk tests using the developed rollator. To measure the motion of the lower limbs, two goniometers were attached to the exteriors of both the knees, and two more were attached to the exteriors of both the ankle joints of the subjects. The results of the pressing forces on the pad measured by the load cells, pad rotations, knee extensions, and ankle rotations were demonstrated. Frequency analyses were performed and correlation coefficients were computed for the obtained results. The relationship between the pad rotation and the motion of the lower limbs was investigated, and the effectiveness of the developed novel rollator in walk assistance was discussed.

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