Many places in the world are too rugged or enclosed for vehicles to access. Even today, material transport to such areas is limited to manual labor and beasts of burden. Modern advancements in wearable robotics may make those methods obsolete. Lower extremity exoskeletons seek to supplement the intelligence and sensory systems of a human with the significant strength and endurance of a pair of wearable robotic legs that support a payload. This article first outlines the use of Clinical Gait Analysis data as the framework for the design of such a system at UC Berkeley. This data is used to design the exoskeleton degrees of freedom and size its actuators. It will then give an overview of one of the control schemes implemented on the BLEEX. The control algorithm described here increases the system closed loop sensitivity to its wearer’s forces and torques without any measurement fromthe wearer (such as force, position, or electromyogram signal). The control algorithm uses the inverse dynamics of the exoskeleton, scaled by a number smaller than unity, as a positive feedback controller. This controller almost destabilizes the system since it leads to an overall loop gain slightly smaller than unity and results in a large sensitivity to all wearer’s forces and torques thereby allowing the exoskeleton to shadow its wearer.

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Stroke is the leading cause of long-term disability in the world. It causes chronic deficits, such as hemiparesis, especially prevalent in the distal upper extremities. An electro-mechanically driven hand orthosis has been developed to assess the potential thera-peutic use of such devices in rehabilitating hand function. A small Direct Current (DC) brushed motor is used as the main actuator, and a cable-driven glove connected to the motor shaft is the central component of the device. The orthosis control is achieved through a force feedback loop using a miniature load cell attached in series to the cable and control module. The later, generates Pulse Width Modulated (PWM) and direction signals required to drive the motor. The speed is determined by the duty cycle of the PWM signal while the direction by the status of a flag bit modified by a user-operated switch. A portable design was achieved by using a 6 V battery pack as the power supply. The device is ready for use in clinical trials with stroke survivor subjects as it has already been tested on healthy individuals with satisfactory per-formance.

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Фантастика стала ещё на один шажок ближе к реальности. Новая рука для робота — это замечательный пример комбинации принципов биомиметики и мехатроники. Увидев её, кто-то непременно вспомнит Терминатора, но изобретение должно найти массу мирных областей применения.

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A high-power electrostatic actuator comprising rotor and stator layers with fault-tolerant electrode structures, a housing to contain the electrodes and dielectric fluid, and electronic circuitry driving a plurality of high-voltage phases. The actuator is constructed from multiple rotor and stator films separated by spacing elements. The electrode structure provides self-alignment for precise assembly. The actuator assembly includes built-in fine-position sensors to allow optimal timing in powering phases, and a coarse position sensor for feedback control. The electrode structure has a large region of linear force to provide low torque-ripple allowing simple high/low voltage pulsing instead of analog high voltage waveforms. Single or double sided flexible circuit manufacturing techniques are used to fabricate the rotor and stator films at low cost.

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This thesis presents a mechanical system design of a haptic cobot exoske-leton for use in physical therapy rehabilitation. The exoskeleton will be the first exoskeleton to offer cobot technology in a wearable haptic device. This exoskeleton provides a significant improvement in existing haptic exoskeleton technology by providing high performance haptic feedback while maximizing the user’s safety. An overall system and subsystem design is presented; which includes a spherical 3RRR mechanism for the shoulder. A detailed design of the shoulder mechanism is presented in five parts: a range of motion study, the kinematic parameters, the kinematics, kinematic optimization and a collision study. The range of motion study is based anatomical data collected using a Flock of Birds motion capture device. The design process for optimization of the shoulder mechanism is presented in which the shoulder mechanism is optimized by examining the Jacobian matrix with the lowest inverse condition number and global condition index. The result is an practical design of a exoskeleton with a high performance shoulder mechanism that is capable of reaching nearly a quarter of workspace developed by the Flock of Birds.

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