Purpose Generally, humanoid robots usually suffer significant impact force when walking or running in a non-predefined environment that could easily damage the actuators due to high stiffness. In recent years, utilization of passive compliant series elastic (SEA) for driving humanoid's joints has proved capability many aspects so far. However, despite being widely applied biped robot research f...

Many successful designs of compliant actuators have been recently proposed. However, the challenge of providing passive and active motion in one actuator has remained. In this paper, a novel mechanism for changing the stiffness of the series elastic actuator over a wide range is presented. An accurate force source is provided by introducing the force control using veloc...

Abstract. This paper deals with robust H∞ force and impedance control of series elastic actuators. It is considered that the series elastic actuators are subject to parametric uncertainties and external disturbances. Robust controllers based on the H∞ criterion have been widely used among robotic applications for guaranteeing good disturbance rejection properties. The H∞ force and impedance con...

In this paper, a force-controllable compact actuator module for a wearable hand exoskeleton system is proposed. To interact with virtual objects naturally with a hand exoskeleton, a small actuator module, which can generate the desired force accurately, is highly required. In the proposed actuator module, a series elastic actuator (SEA) mechanism was applied for the force mode control. Based on...

Series elastic actuators (SEA) are playing an increasingly important role in the fields of physical human-robot interaction. This paper focuses on the modeling and control of a cable-driven SEA. First, the scheme of the cable-driven SEA has been proposed, and a velocity controlled DC motor has been used as its power source. Based on this, the model of the cable-driven SEA has been built up. Fur...

Currently, the mobility of above-knee amputees is limited by the lack of available prostheses that can efficiently replicate biologically accurate movements. In this study, a powered knee prosthesis was designed utilizing a novel mechanism, known as a clutchable series-elastic actuator (CSEA).The CSEA includes a low-power clutch in parallel with an electric motor within a traditional series-ela...