This paper presents a knee-joint model to provide a better understanding on the interaction between natural joints and artificial mechanisms for design and control of rehabilitation exoskeletons. The anatomically based knee model relaxes several commonly made assumptions that approximate a human knee as engineering pin-joint in exoskeleton design. Based on published MRI data, we formulate the k...

BACKGROUND In this paper we propose the use of global Kalman filters (KFs) to estimate absolute angles of lower limb segments. Standard approaches adopt KFs to improve the performance of inertial sensors based on individual link configurations. In consequence, for a multi-body system like a lower limb exoskeleton, the inertial measurements of one link (e.g., the shank) are not taken into accoun...

Series elastic actuators have been widely used in humanrobot interactive systems due to their high controllability and improved human experience. One such system is the powered ankle exoskeleton. In [1], the torque control of a tethered ankle exoskeleton with a coil spring (Fig. 1) was investigated, which showed that the combination of model-free, integration-free feedback control and iterative...

Integrating an exoskeleton as the external apparatus for a brain–machine interface (BMI) has the advantage of providing multiple contact points to determine body segment postures and allowing control to and feedback from each joint. When using macaques as subjects to study the neural control of movement, an upper limb exoskeleton design with unlikely singularity is required to guarantee safe an...

Exoskeletons have been used for human performance restoration and enhancement for many years. Due to the dynamic nature of human locomotion, torque control is widely used in lower-limb exoskeleton assistance during stance phases of walking. In these systems, series-elastic actuators (SEA) are commonly used to provide low error torque tracking in the presence of unknown and changing human dynami...

Locusts jump by using a catapult mechanism in which energy produced by slow contractions of the extensor tibiae muscles of the hind legs is stored in distortions of the exoskeleton, most notably (1) the two semi-lunar processes at each knee joint and (2) the tendons of the extensor muscles themselves. The energy is then suddenly released from these stores to power the rapid, propulsive movement...

The present study identifies the mechanics of planar reaching movements performed by monkeys (Macaca mulatta) wearing a robotic exoskeleton. This device maintained the limb in the horizontal plane such that hand motion was generated only by flexor and extensor motions at the shoulder and elbow. The study describes the kinematic and kinetic features of the shoulder, elbow, and hand during reachi...

When arm movements are perturbed by a load, how does the nervous system adjust control signals to reduce error? While it has been shown that the nervous system is capable of compensating for the effects of limb dynamics and external forces, the strategies used to adapt to novel loads are not well understood. We used a robotic exoskeleton [kinesiological instrument for normal and altered reachin...

Robotic exoskeleton is getting important to human in many aspects such as power assist, muscle training, regain motor function and rehabilitation. The research and development towards these functions are expected to be combined and integrated with the human intelligent and machine power, eventually becoming another generation of robot which will enhance the machine intelligent and human power. ...

Rehabilitation of the upper extremities, especially the hands, is critical for the restoration of independence in activities of daily living for individuals suffering from hand disabilities. There are currently two major challenges in developing robotic devices for hand rehabilitation: (1) design of a device that is compatible with the complex geometry and nonlinear biomechanics of the human ha...