Lower extremity exoskeleton intelligent carrying system is a new concept human-machine intelligent robot system. To provide a virtual experiment platform for the system, virtual prototyping technique is used to build up a human-machine carrying exoskeleton system, which is benefit to study the kinematics and dynamics characteristics, speed up the development of prototype. The dynamic model of exoskeleton for the integral movement is established, and the virtual joint nonlinear adaptive torque control is provided to complete the walking experiment. Simulation results show the validity of this the virtual platform and the control method.

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Haptics is the discipline that deals with the study of the complex sense of touch as an interface between human beings and machines. Haptic technology has been proven applicable and practical in many fields, including scientific visualization, medical training, authentication and other areas such as education and arts. This research investigates the usage of haptics as a mechanism to extract users’ behaviors and to build a biometric system for authentication. We captured human behavior while users were interacting with two haptic devices: the Desktop PHANToM device (single-point interaction) and the CyberForce system (hand exoskeleton device). Experimental results, based on a set of haptic-based applications, show that single-point interaction haptic devices are suitable for authentication purposes. On the other hand, multiple-point haptic devices —hand exoskeleton devices-still seem to be far from being used in a haptic-biometric system. When using hand exoskeleton devices, the extracted features are not a good source of rich information to characterize a biometric identifier system.

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It is the goal of this paper to present performance differences between a Direct Drive master actuator (DD) and a Bowden Cable relocated master actuator (BCD) in a typical force-feedback tele-manipulation experiment with a virtual slave. The BCD actuator is a candidate actuator for implementation in a wearable exoskeleton, in order to reduce mass and inertia on each joint of the movable structure. The BCD performance matches the one of the DD in terms of torque and position tracking in a 4 channel control. The maximum rendered contact stiffness is suitable for implementation in the ESA human arm exoskeleton, with a maximum of about 36 Nm/rad. When, instead of the DD, a relocated BCD actuator is implemented in an exoskeletons movable structure, the mechanical output power-density can be increased by more than 5 fold up to 31 mNm/cm³, with comparable performance. The specific power is then increased by more than 6 fold, to 13 Nm/kg. The Bowden Cable transmission wrapping angle alters the free movement friction only marginally by about 50 mNm only. The tracking performances are hardly affected and the contact stiffness increases with increasing wrapping angle. Transmission wrapping angles of up to 270 Deg. are tested.

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This paper deals with the design and the testing of an exoskeleton system able to catch the angular deflections of every phalanges of three fingers. It has to be placed on the back of the human hand, giving the possibility to measure with great precision the rotation of every phalange. The system is composed of a mechanical exoskeleton, working with a micro-encoder like position sensor. A smart unit based on a microprocessor, endowed with a dedicated card, was also designed in order to make the system more compatible with every computer. The system is studied as a standalone device sending and receiving data through the RS232 serial line, and is able to calibrate and to interpret commands by means of dedicated software. This way the system is flexible and precise

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This paper presents design, implementation and control of a 3RPS-R exoskeleton, specifically built to impose targeted therapeutic exercises to forearm and wrist. Design of the exoskeleton features enhanced ergonomy, enlarged workspace and optimized device performance when compared to previous versions of the device. Passive velocity field control (PVFC) is implemented at the task space of the manipulator to provide assistance to the patients, such that the exoskeleton follows a desired velocity field asymptotically while maintaining passivity with respect to external applied torque inputs. PVFC is augmented with virtual tunnels and resulting control architecture is integrated into a virtual flight simulator with force-feedback. Experimental results are presented indicating the applicability and effectiveness of using PVFC on 3RPS-R exoskeleton to deliver therapeutic movement exercises.

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