The superb ability of animals to negotiate rough terrain has caused engineers to focus on mechanical properties of muscle and other unique features in order to design improved robots for exploration. This paper reviews recent work in artificial muscle actuators, as well as a new sensor based on a robotic model of the muscle spindle cell. The actuator contains a pneumatic force generator in para...

Lumbar support exoskeletons with active and passive actuators are currently the cutting-edge technology for preventing back injuries in workers while lifting heavy objects. However, many challenges still exist both types of exoskeletons, including rigid actuators, risks human–robot interaction, high battery consumption, bulky design, limited assistance. In this paper, design a compact, lightwei...

Piezoelectric actuators (PEAs) have been widely used in micro- and nanopositioning applications due to their fine resolution, rapid responses, and large actuating forces. However, a major deficiency of PEAs is that their accuracy is seriously limited by hysteresis. This paper presents adaptive model predictive control technique for reducing hysteresis in PEAs based on autoregressive exogenous m...

We consider energy transfer from an elastic actuator to load, and show that the can be optimized by tuning Young's modulus of impedance matching host material.

A vision-based approach to the motion control of pneumatic group actuators is presented. Sensing of plate locations consisting of the pneumatic group actuator is essential to cope with the variation of elastic tubes of the actuator. Plate locations are measured by a vision system and the motion of the actuator is controlled using a roughly identified relationship between air pressure imposed on...

We present a new haptic augmented reality system that modulates the perceived stiffness of a real object by changing the perceived material with vibratory subtraction and addition. Our system consists of a stick with a vibrotactile actuator and a pad with an elastic sheet. When a user taps the pad, the innate vibration resulting from the tapping is absorbed by the elastic surface. Simultaneousl...

The authors present in this paper a robust torque control of an active orthosis designed to assist the knee joint flexion/extension during physical therapy. The orthosis is driven by a rotary Series Elastic Actuator presented in authors’ previous paper. The adopted control strategy is based on H∞ criterion in order to ensure good system performance even when it is subjected to parametric uncert...

This research aims at developing a magnetic resonance (MR)-compatible equivalent of an exoskeleton used for wrist movement rehabilitation therapy of neurological patients. As a crucial step towards the accomplishment of this goal, this paper investigates the development of a novel actuation architecture suitable for interaction control in MR environments, the MR-SEA (SEA stands for Series Elast...

This paper presents the modular design and control of a novel variable impedance compact compliant wearable ankle robot (powered Ankle-Foot Orthosis, AFO) for overground gait rehabilitation and assistance mainly for stroke patients. Design of AFO, its construction, kinematics, working principle, actuation, control etc. are described. A novel variable impedance compact compliant series elastic a...