Autonomous grasping in dynamic environments where the object the robot or both are moving is an increasingly common task in robotic applications This thesis describes an online trajectory planner a geometric controller which evaluates a nonlinear memoryless function to map the current object position and velocity into a desired robot pose If the robot tracks these set points it is guaranteed to match the object s velocity and acceleration on a specied grasp surface A planar simulation demonstrates that this paradigm performs favorably when compared with the traditional planning approach Since it does not depend on future state predictions no object model is required Without trajectory prediction the computational effort is drastically reduced allowing for higher controller speed and tracking feedback gains The geometric controller has been successfully implemented on the dof Sarcos Dextrous Arm In order to provide the critical local sensing just before robotenvironment contact this thesis reports on work in progress towards the development of a proximity sensing network located in a robots multingered gripper This network will form an integral part of a multistage sensing system with vision and tactile sensor pads Sensing information is passed on to geometric controller which provides a framework for general sensorbased control of robotic tasks

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The object detection apparatus according to the invention detects an object based on input images that are captured sequentially in time in a moving unit. The apparatus generates an action command to be sent to the moving unit, calculates flow information for each local area in the input image, and estimates an action of the moving unit based on the flow information. The apparatus calculates a difference between the estimated action and the action command and then determines a specific local area as a figure area when such difference in association with that specific local area exhibits an error larger than a predetermined value. The apparatus determines presence/absence of an object in the figure area.

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A method for obtaining an assist torque to be applied to a human joint, in a human assist system for applying an assist torque to the human joint to reduce load of muscles, and the human assist system are provided. The method comprises the step of obtaining a moment due to gravity, acting on a joint of each human segment, based on equations of force and moment balance on each segment. The method further comprises the step of obtaining an assist torque to be applied to the joint to compensate for the moment due to gravity, acting on the joint. The human assist system comprises a motor for delivering an assist torque to a joint and a motor driver for driving control of the motor. The system further comprises a controller for determining a desired value of an assist torque, comprising a processor and a memory. The controller is configured to obtain a moment due to gravity, acting on a joint of each human segment, based on equations of force and moment balance on each segment and then to obtain an assist torque to be delivered to the joint to compensate for the moment due to gravitational acceleration at the joint. The method provides a natural subdivision between the voluntary actuators which are responsible for forward progression of motion and the assist actuators which are responsible for preserving static equilibrium. This subdivision may mitigate the interference between voluntary control and artificial control.

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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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This paper presents a hand rehabilitation support system for self-performing rehabilitation therapies. The developed system consists of hand exoskeleton device, which provides individual finger joint motion for disabled persons, and a lateral symmetric master-slave motion assistant system joined with virtual reality (VR) environment. Most of disability caused by CVA (Cerebral Vascular Accident) or bone fracture are hemiplegia where impaired hand is only in one side. Based on the peculiarity of this disability, we adopted a symmetric master-slave motion assistant system in which the impaired hand is driven by the healthy hand in the opposite side.

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