TY - GEN
T1 - Online compensation of gravity and friction for haptics with incremental position sensors
AU - Fukushima, Satoshi
AU - Sekiguchi, Hiromu
AU - Saito, Yuki
AU - Nozaki, Takahiro
AU - Ohnishi, Kouhei
N1 - Publisher Copyright:
© 2017 IEEE.
PY - 2017/12/14
Y1 - 2017/12/14
N2 - This paper proposes an online compensation method of gravity and friction by least squares method (LSM) for robots implementing haptics. In order to expand the range of tasks using the robot such as telepresence robot, implementing haptics technology is essential. However, with higher gear ratio motors, the friction lowers the quality of the haptic transmission. In order to comfortably control the robot with haptics, compensation of gravity and friction torques are essential. In the case of bilateral control, incremental position encoders are often used because they are easy to use at low cost. However, with the conventional method, the control start position must always be returned to the same initial value in order achieve the gravity torque compensation, as the value of the angle can not be stored with incremental encoders. In order to estimate and compensate the gravity and friction torque from any starting position of the robot, this paper proposes a new online compensation method using LSM while achieving the bilateral control. Using the proposed method, the absolute encoder is not necessary, and no matter where the starting position of the control is, the gravity torque and friction torque can be compensated, allowing a comfortable control for the operator. The validity of the proposed method was confirmed by the experiment.
AB - This paper proposes an online compensation method of gravity and friction by least squares method (LSM) for robots implementing haptics. In order to expand the range of tasks using the robot such as telepresence robot, implementing haptics technology is essential. However, with higher gear ratio motors, the friction lowers the quality of the haptic transmission. In order to comfortably control the robot with haptics, compensation of gravity and friction torques are essential. In the case of bilateral control, incremental position encoders are often used because they are easy to use at low cost. However, with the conventional method, the control start position must always be returned to the same initial value in order achieve the gravity torque compensation, as the value of the angle can not be stored with incremental encoders. In order to estimate and compensate the gravity and friction torque from any starting position of the robot, this paper proposes a new online compensation method using LSM while achieving the bilateral control. Using the proposed method, the absolute encoder is not necessary, and no matter where the starting position of the control is, the gravity torque and friction torque can be compensated, allowing a comfortable control for the operator. The validity of the proposed method was confirmed by the experiment.
KW - Bilateral control
KW - gravity and friction compensation
KW - haptics
KW - least squares method
KW - telepresence robot
UR - http://www.scopus.com/inward/record.url?scp=85048471974&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=85048471974&partnerID=8YFLogxK
U2 - 10.1109/M2VIP.2017.8211458
DO - 10.1109/M2VIP.2017.8211458
M3 - Conference contribution
AN - SCOPUS:85048471974
T3 - 2017 24th International Conference on Mechatronics and Machine Vision in Practice, M2VIP 2017
SP - 1
EP - 6
BT - 2017 24th International Conference on Mechatronics and Machine Vision in Practice, M2VIP 2017
PB - Institute of Electrical and Electronics Engineers Inc.
T2 - 24th International Conference on Mechatronics and Machine Vision in Practice, M2VIP 2017
Y2 - 21 November 2017 through 23 November 2017
ER -