Multi-Degree-of-Freedom Motion-Copying System Considering Variation in Friction

Abstract

This paper proposes a motion-reproduction method for a multi-degree-of-freedom system. For storing and reproduction of haptic information, a motion-copying system was proposed. Reproducing the saved motion using this method is difficult when the environmental configuration in the motion-loading phase is different from that in the motion-saving phase. There are several methods for adapting to the variation in environmental configuration. In the conventional method, it is considered that the orthogonal axes are controlled independently. However in the tracing motion, friction and interference exist between the orthogonal axes. Thus, it is impossible to reproduce the saved motion when the coefficient of friction varies. In this paper, friction in a two degree-of-freedom system is modeled and a motion-copying system using the modeled friction is proposed. The proposed method reproduces the saved motion even when the coefficient of friction varies. To validate the proposed method, experiments were conducted.

Inertia Compensation of Motion Copying System for Dexterous Object Handling

“…The estimated viscous friction data can be used in RFOB to estimate the accurate reaction force in the motion copying system. If there exists friction variation between the motion saving phase and the motion reproduction phase, the method proposed in (22) can be used. Phuong et al proposed a friction free disturbance observer with a dither signal for the motion copying system, which can be used both in motion saving and loading (23) .…”

Recent advances and outlook in industrial instrumentation and mechatronics control

“…The disturbance observer (DOB) is often termed as the pronoun of motion control technology. Hence, majority of papers related to motion control in IEEJ J. IA are related to DOB .…”

“…These include the extended or modified DOB, and they estimate the special components in the disturbances. Advanced DOBs consist of the following types: The most significant advanced DOB is the reaction force observer (RFOB) , ,. This includes the assumption that a robot makes contact with an environment such as a flat wall.…”

“…Haptics is expected to be widely useful for interactions between mechatronic sys‐tems and humans ,. As defined in a survey paper , ‘Haptics is a research field that examines information from physical interaction between humans and objects.…”

“…Recent studies in IEEJ J. of IA and a few other journals use a new technical word ‘motion copying system’ . A motion copying system includes a technology wherein force, tactile, and position information is recorded and reproduced (see Fig.…”