Robotic systems such as exoskeletons can be effectively used in the reduction of fatigue and musculoskeletal disorders (MSD) associated with physical tasks, but robots which work in physical contact with humans pose problems with user safety. A novel approach to developing intrinsically safe robots is to use passive actuators which have the advantage of being safer, ensuring stability, high force/weight ratios and lower power consumption. It is however not clear how effective an exoskeleton utilizing passive actuators would be in reducing fatigue and the risk of MSD. This paper analyzes the benefit of using such a system with results from dynamic simulations and an experiment using a specially designed mechanism used for evaluation. Results indicate that fatigue and effort could be reduced if robot impedance is minimized. Experiments also highlighted issues of implementing such a system into practice.

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Raytheon Sarcos’s second-generation exoskeleton robotics suit, XOS 2, which was named one of Time magazine’s 50 Best Inventions last year, is now a mere five years away from production, its inventors say.

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This paper presents a virtual reality (VR)-enhanced new hand rehabilitation support system that enables patients to exercise alone. This system features a multi-degrees-of-freedom (DOF) motion assistance robot, a VR interface for patients, and a symmetrical master—slave motion assistance training strategy called «self-motion control,» in which the stroke patient’s healthy hand on the master side creates the assistance motion for the impaired hand on the slave side. To assist in performing the fine exercise motions needed for functional recovery of the impaired hand, the robot was constructed in an exoskeleton with 18 DOFs, to assist finger and thumb independent motions such as flexion/extension and abduction/adduction, thumb opposability, and hand—wrist coordinated motions. To enhance the effectiveness of the exercises, audio-visual instructions of each training motion using VR technology were designed with the input of clinician researchers. Experimental results from healthy subjects and patients show sufficient performance in the range of motion of the robot as well as sufficient assistance forces.

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Advanced robotics needs a new breed of actuators, capable to exhibit a large number of desirable features, ranging from high power/torque density, high efficiency, zero backlash and low noise, to low reflected mechanical impedance, high bandwidth and accuracy. Even if it is quite evident that to fully match these requirements new basic actuation principles have to be investigated and developed in the long term, there is still scope now for innovating the field by combining mature components into new actuation schemes. This paper reports the development and the experimental evaluation of a new actuator, aiming at improving the torque density and the mechanical efficiency. The device has shown impressive performances being able to exert up to 500Nm continuous torque and 800Nm peak torque with 85% mechanical efficiency and zero backlash, up to 60°/s maximum output speed for a total weight of just 6Kg, comprising the structural case covering the internal mechanics. The actuator has been expressly conceived as an actuation module to be integrated in a fully powered whole body exoskeleton intended for material handling in tight and unstructured environments (see Fig.1).

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When Licklider published Man-Computer Symbiosis in 1960, he stated that ldquoIt seems entirely possible that, in due course, electronic or chemical ldquomachinesrdquo will outdo the human brain in most of the functions we now consider exclusively within its province. (p.2)rdquo The brain-machine interface Licklider envisioned has been extended beyond his initial conceptions by noninvasive and portable technologies, such as EEG and near-infrared based optical brain imaging devices. These noninvasive neuroimaging tools facilitate better interfacing with the brain by providing the underlying principles that govern the brain’s ability to adapt to and utilize new interface paradigms. Moreover, these enabling technologies can guide the development of prosthetics to compensate for cognitive deficits within impaired populations, as well as enhance cognitive performance for healthy populations. Functional near-infrared spectroscopy (fNIR), an emerging optical brain imaging system, will be introduced along with an illustration of its potential role in the development of cognitive prostheses. fNIR is a wearable neuroimaging device that enables the continuous, non-invasive, and portable monitoring of NIR light absorbance of oxygenated and deoxygenated hemoglobin in blood. Hemodynamics measured by fNIR is similar to functional MRI and provides information about ongoing brain activity. Drexel’s Optical Brain Imaging Lab, comprised of an interdisciplinary team of engineers, cognitive and motor neuroscientists, and neurorehabilitation scientists have developed and integrated fNIR imaging techniques into an array of research paradigms to assess cognitive and motor activities of individuals with and without impairments. Applications of fNIR include cognitive workload and human performance assessments, credibility assessments, learning during performance of a gripping task with an electromyographically controlled exoskeleton gripper with haptic feedback, assessment of recovery from — anesthesia, and brain-machine interface for communication and control. This talk will briefly address current developments of cognitive prostheses as well as the future direction of the field.

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