新型可変剛性直列弾性アクチュエータの設計と制御
Design and Control of a Novel Variable Stiffness Series Elastic Actuator
モジュール式設計で広い剛性範囲と高いトルク密度を実現した可変剛性直列弾性アクチュエータを開発し、従来のPID制御で位置・力の高精度追従が可能なことを示した。
著者: Emre Sariyildiz, Rahim Mutlu, Jon Roberts, Chin-Hsing Kuo, Barkan Ugurlu
分類: cs.RO
原文アブストラクト
This paper expounds the design and control of a new Variable Stiffness Series Elastic Actuator (VSSEA). It is established by employing a modular mechanical design approach that allows us to effectively optimise the stiffness modulation characteristics and power density of the actuator. The proposed VSSEA possesses the following features: i) no limitation in the work-range of output link, ii) a wide range of stiffness modulation (~20Nm/rad to ~1KNm/rad), iii) low-energy-cost stiffness modulation at equilibrium and non-equilibrium positions, iv) compact design and high torque density (~36Nm/kg), and v) high-speed stiffness modulation (~3000Nm/rad/s). Such features can help boost the safety and performance of many advanced robotic systems, e.g., a cobot that physically interacts with unstructured environments and an exoskeleton that provides physical assistance to human users. These features can also enable us to utilise variable stiffness property to attain various regulation and trajectory tracking control tasks only by employing conventional controllers, eliminating the need for synthesising complex motion control systems in compliant actuation. To this end, it is experimentally demonstrated that the proposed VSSEA is capable of precisely tracking desired position and force control references through the use of conventional Proportional-Integral-Derivative (PID) controllers.
