dVRKロボットアームの非線形外乱力を考慮した信頼性の高い重力補償制御
A Reliable Gravity Compensation Control Strategy for dVRK Robotic Arms With Nonlinear Disturbance Forces
dVRKのMTMに生じる非線形なケーブル外乱力を高次多項式でモデル化し、MLSEで重力・外乱パラメータを逐次同定する重力補償法を提案。広い作業空間で従来法を上回る精度を実験で示し、MATLAB/C++パッケージを公開した。
著者: Hongbin Lin, C. W. Vincent Hui, Yan Wang, Anton Deguet, Peter Kazanzides, K. W. Samuel Au
分類: cs.RO
原文アブストラクト
External disturbance forces caused by nonlinear springy electrical cables in the Master Tool Manipulator (MTM) of the da Vinci Research Kit (dVRK) limits the usage of the existing gravity compensation methods. Significant motion drifts at the MTM tip are often observed when the MTM is located far from its identification trajectory, preventing the usage of these methods for the entire workspace reliably. In this paper, we propose a general and systematic framework to address the problems of the gravity compensation for the MTM of the dVRK. Particularly, high order polynomial models were used to capture the highly nonlinear disturbance forces and integrated with the Multi-step Least Square Estimation (MLSE) framework. This method allows us to identify the parameters of both the gravitational and disturbance forces for each link sequentially, preventing residual error passing among the links of the MTM with uneven mass distribution. A corresponding gravity compensation controller was developed to compensate the gravitational and disturbance forces. The method was validated with extensive experiments in the majority of the manipulator's workspace, showing significant performance enhancements over existing methods. Finally, a deliverable software package in MATLAB and C++ was integrated with dVRK and published in the dVRK community for open-source research and development.
