In October 2003, the first functional loadbearing and energetically autonomous exoskeleton, called the Berkeley Lower Extremity Exoskeleton (BLEEX) was demonstrated, walking at the average speed of two miles per hour while carrying 75 pounds of load. The project tackled four fundamental technologies: the exoskeleton architectural design, a control algorithm, a body LAN to host the control algorithm, and an on-board power unit to power the actuators, sensors and the computers. This article gives an overview of the BLEEX project.

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This thesis is aimed toward the development and evaluation of a novel active ankle foot orthosis (AAFO) based on shape memory alloy (SMA) actuators. This device intends to fill the gap in the existing research aimed at helping patients with drop foot muscle deficiencies as well as rehabilitation activities. To examine the feasibility of this idea, the current study focuses on the dynamic behavior of the ankle joint. A SMA manipulator with a similar dynamic behavior is experimentally evaluated. Nonlinear behavior of SMA wires requires nonlinear control techniques such as Sliding Mode Controller (SMC) for tracking the desired ankle angle. Simulation results of several different techniques are compared (PID, SMC, SMC-PID and Adaptive PID) and finally the experimental result of an Adaptive PID is used to check the stability of walking. This results shows that an Adaptive PID controller as a robust and precision control can be used to track the desired position of the ankle. However for frequencies more than 0.25 Hz (time cycle less than 4 seconds), the walking conditions will be unstable due to slow cooling process.

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Although autonomous robotic systems perform remarkably in structured environments (e.g., factories), integrated human–robotic systems are superior to any autonomous robotic systems in unstructured environments that demand significant adaptation. The technology associated with exoskeleton systems and human power augmentation can be divided into lower-extremity exoskeletons and upper-extremity exoskeletons. The reason for this was twofold; firstly, one could envision a great many applications for either a stand-alone loweror upper-extremity exoskeleton in the immediate future. Secondly, and more importantly for the division, is that these exoskeletons are in their early stages, and further research still needs to be conducted to ensure that the upper-extremity exoskeleton and lower-extremity exoskeleton can function well independently before one can venture an attempt to integrate them.

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The seven degree of freedom arm model is widely used in robotics, computer graphics, and much more. For wearable robotic systems, which are subject to joint limits, it is desirable to relate the joint limits to the redundantly of the system. A brief review of the arm model, redundant space and kinematics is presented. Following this review a closed form method is developed calculate the interval of the swivel angle (which characterizes the redundancy) that produces arm configurations that stay within joint limits.

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Nowadays, personal communication devices such as mobile phones are very popular all over the world. The success of mobile phones lies in the fact that interpersonal communication and interface is vital to the well-being of humans, and mobile phones help people achieve this goal by extending the sense of hearing and power of speech to far away places conveniently. However, apart from the auditory sense, humans also possess other senses for communication and interaction such as vision and body motion. These sensations play very important roles in our everyday interpersonal communication. In terms of technology, the state-of-the-art in sensing hardware, control software, telecommunication protocol, and computer networks has already allowed various forms of data to be transmitted and analyzed efficiently. So why can’t we find multimodal sensation communication commonplace among the mobile devices? We believe that the lack of efficient human–machine interfaces has caused a bottleneck. Therefore, we have designed and built a series of mobile devices that possess perceptual powers and communication capabili-ties and can support intelligent interactions. We call this novel class of devices intelligent wearable interfaces.

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