TY - GEN
T1 - Evaluation of treadmill velocity control based on user's intention of acceleration or deceleration
AU - Nakashima, Yasutaka
AU - Ando, Takeshi
AU - Kobayashi, Yo
AU - Fujie, Masakcitsu G.
PY - 2014/10/24
Y1 - 2014/10/24
N2 - We have been developing a new mobility-aid robotic vehicle, 'Tread-Walk 2 (TW-2)', which supports walking for the elderly. TW-2 is controlled by natural walking movements, particularly ground reaction force, during gait. However, in our previous work, a user of this vehicle experienced some discomfort both when he started walking and when he stopped walking. This problem was caused by inaccurate estimation of the user's anteroposterior force at the heel contact and the toe off. The estimation of the user's anteroposterior force is closely related to the inaccurate estimation of the vertical component of the ground reaction force, which is approximated by a square waveform in the stance phase. In this paper, we evaluate a novel treadmill control algorithm that allows the anteroposterior force to be estimated more accurately. To evaluate how well the treadmill control algorithm is capable of acceleration and deceleration in accordance with the intention of the operator, we measure the transformation of walking velocity and kicking power, and the trajectory of the toe position produced by the proposed controller and the previous one compared with level ground walking. The results show that the proposed control algorithm allows the actual walking velocity of the participant to track and converge to the target velocity, while the participant using the previous controller is unable to follow the target velocity and shows no convergence when the velocity is reduced from 2.0 to 1.0 km/h. Thus, when using the proposed controller, walking velocity decreases as the user reduces anteroposterior force, similarly to level ground walking.
AB - We have been developing a new mobility-aid robotic vehicle, 'Tread-Walk 2 (TW-2)', which supports walking for the elderly. TW-2 is controlled by natural walking movements, particularly ground reaction force, during gait. However, in our previous work, a user of this vehicle experienced some discomfort both when he started walking and when he stopped walking. This problem was caused by inaccurate estimation of the user's anteroposterior force at the heel contact and the toe off. The estimation of the user's anteroposterior force is closely related to the inaccurate estimation of the vertical component of the ground reaction force, which is approximated by a square waveform in the stance phase. In this paper, we evaluate a novel treadmill control algorithm that allows the anteroposterior force to be estimated more accurately. To evaluate how well the treadmill control algorithm is capable of acceleration and deceleration in accordance with the intention of the operator, we measure the transformation of walking velocity and kicking power, and the trajectory of the toe position produced by the proposed controller and the previous one compared with level ground walking. The results show that the proposed control algorithm allows the actual walking velocity of the participant to track and converge to the target velocity, while the participant using the previous controller is unable to follow the target velocity and shows no convergence when the velocity is reduced from 2.0 to 1.0 km/h. Thus, when using the proposed controller, walking velocity decreases as the user reduces anteroposterior force, similarly to level ground walking.
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U2 - 10.1109/WAC.2014.6936042
DO - 10.1109/WAC.2014.6936042
M3 - Conference contribution
AN - SCOPUS:84908884683
T3 - World Automation Congress Proceedings
SP - 555
EP - 560
BT - World Automation Congress Proceedings
PB - IEEE Computer Society
T2 - 2014 World Automation Congress, WAC 2014
Y2 - 3 August 2014 through 7 August 2014
ER -