To overcome some of the difficulties of robotic teleoperation using hand controllers, a new approach is necessary, namely gesture-based control. A review of sensors currently in use for human joint angle measurement is presented. Based on this review, a method was chosen that uses a variable-length fiber optic sensor. Several different types of optical fibers, along with a variety of test configurations, were initially evaluated, and the most promising of these were selected for further testing. This thesis describes these methods of evaluation and the final system design and testing of a wearable system for gesture-based control of a robotic manipulator, including a discussion of sensor placement to obtain improved results. The final system presented requires improvements and continued research to become usable for robotic control. However, the basic concept and design are shown to provide reliable information regarding relative human joint motion.

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Exoskeletons for human performance augmentation (EHPA) are controlled and wearable devices and machines that can increase the speed, strength, and endurance of the operator. EHPA is expected to do that by increasing the physical performance of the solider wearing it, including:
• Increased payload: more fire power, more supplies, and thicker and heavier armor
increasing the soldier chance of surviving a direct hit or even an explosion.
• Increased speed and extended range: enhanced ground reconnaissance and battle space
dominance.
• Increased strength: larger caliber weapons, obstacle clearance, repairing heavy ma
chinery such as tack.

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We used a lower limb robotic exoskeleton controlled by the wearer’s muscle activity to study human locomotor adaptation to disrupted muscular coordination. Ten healthy sub-jects walked while wearing a pneumatically powered ankle exoskeleton on one limb that effectively in-creased plantar flexor strength of the soleus muscle. Soleus electromyography amplitude controlled plantar flexion assistance from the exoskeleton in real time. We hypothesized that subjects’ gait kinematics would be initially distorted by the added exoskeleton power, but that subjects would reduce soleus muscle recruitment with practice to return to gait kinematics more similar to normal. We also examined the abi-lity of subjects to recall their adapted motor pattern for exoskeleton walking by testing subjects on two separate sessions, 3 days apart. The mechanical power added by the exoskeleton greatly perturbed ankle joint movements at first, causing subjects to walk with significantly increased plantar flexion during stance. With practice, subjects reduced soleus recruitment by 35% and learned to use the exoskeleton to perform almost exclusively positive work about the ankle. Subjects demonstrated the ability to retain the adapted locomotor pattern between testing sessions as evidenced by similar muscle activity, kinematic and kinetic patterns between the end of the first test day and the beginning of the second. These results demonstrate that robotic exoskeletons controlled by muscle activity could be useful tools for testing neural mechanisms of human locomotor adaptation.

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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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