The inherent strength of robotic manipulators can be used to assist humans in performing heavy lifting tasks. These robots reduce manpower, reduce fatigue, and increase productivity. This thesis deals with the development of a control system for a robot being built for this purpose. The task for this robot is to lift heavy payloads while performing complex insertion tasks. This task must be completed on the deck of a naval vessel where possible disturbances include wind, rain, poor visibility, and dynamic loads induced by a swaying deck. The primary objective of the control-ler being designed here is to allow for insertion of the payload despite tight positioning tolerances and disturbances like surface friction, joint friction, and dynamic loads from ship motions. A control struc-ture designed for intuitive interaction between the robot and operator is analyzed and shown to be stable using an established environment interaction model. The controller is shown to perform within established specifications via numerical simulation based on simple user inputs. An additional objective of this con-troller design is to prevent part jamming during the insertion task. With a large, powerful manipulator, the chances of a jam occurring is high. Without the use of bilateral force feedback, it will be difficult for the operator feel when these jams will occur and there will be no information about how to prevent them. This thesis analyzes the geometry and mechanics of the jamming problem and derives a control system to assist the user in preventing these jams. These methods can be extended to other insertion tasks simply by specifying the appropriate geometry.

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Loss of function after SCI, ABI or stroke has a marked affect on ones quality of life. Return of function has been a long-standing goal of physical and occupational therapy. Repeated motor practice has been identified as crucial for motor recovery. The development of a robotic device for neuromotor rehabilitation and upper extremity neuromuscular system recovery is described. The actuator mechanism allows free motion when possible, and provides programmable therapeutic levels of resistance. The sensor system allows characterization of the applied forces, and accurate measurement of the range of motion of the joint. The control system provides real time feedback of actuator commands based on sensor data, calibration routines, and operational modes.

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In this paper, a mouse-shaped haptic device is proposed. The device solves conventional problems of previously developed devices such as structure and control complexity and operating difficulties. We adopted multiple finger inputs in order to carry out complicated tasks and in order to highly adapt to the environment. To develop the multi-fingered haptic device, we focused on anatomical knowledge and neurophysiology. Since there is a primacy of the visual information over somatic sensation, we believe the movable range of human fingers does not necessarily have to be completely satisfied, i.e. visual information can compensate for the difference between the displacement of the haptic device and that of the slave device in a master-slave system. We applied this feature to miniaturize and simplify the device. To confirm the usefulness of our developed device for a virtual reality system, we carried out three experiments: position control, familiarization and force feedback. The results show the effectiveness of the developed haptic device.

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A high-quality haptic interface is typically characterized by low apparent inertia and damping, high structural stiffness, minimal backlash and absence of mechanical singu-larities in the workspace. In addition to these specifications, exoskeleton haptic interface design involves consideration of additional parameters and constraints including space and weight limitations, workspace requirements and the kinematic constraints placed on the device by the human arm. In this context, we present the design of a five degree-of-freedom haptic arm exoskeleton for training and rehabi-litation in virtual environments. The design of the device, including actuator and sensor selection, is discussed. Limitations of the device that result from the above selections are also presented. The device is capable of providing kinesthetic feedback to the joints of the lower arm and wrist of the operator, and will be used in future work for robot-assisted rehabilitation and training.

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A robotic exoskeleton and a control system for driving the robotic exoskeleton, including a method for making and using the robotic exoskeleton and its control system. The robotic exoskeleton has sensors embedded in it which provide feedback to the control system. Feedback is used from the motion of the legs themselves, as they deviate from a normal gait, to provide corrective pressure and guidance. The position versus time is sensed and compared to a normal gait profile. Various normal profiles are obtained based on studies of the population for age, weight, height and other variables.

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