振動抑制効果を考慮したロボットアームの最適位置指令設計法

抄録

In motion control applications, servo drive systems have widely applied to various load systems with complicated mechanisms. A robot arm with flexible joints is one of typical examples and it forms multi-mass resonant systems which generate mechanical vibration. Since such vibration gives tracking errors in motion and/or increase of settling time, the vibration suppression is indispensable to achieve the high performance robot arm motion. Many schemes such as model-based feedforward control and modern control theory-based feedback control have been proposed to overcome those problems.
This paper presents a new feedforward control scheme using optimal control command shaping to suppress the resonant vibration in robot arm motion. By analyzing characteristics of the conventional position controller with the S-shaped position command, an optimal command design can be examined to eliminate the resonant vibration. Based on these analyses, a new command shaping algorithm is proposed. The proposed feedforward scheme can obtain the same vibration suppression characteristics as those by the conventional feedback schemes, regardless of the simple input position command shaping. Experimental results with a prototype show an effectiveness of the proposed control.