Using pre-recorded human motion and trajectory tracking, we can control the motion of a humanoid robot for free-space, upper body gestures. However, the number of degrees of freedom, range of joint motion, and achievable joint velocities of today’s humanoid robots are far more limited than those of the average human subject. In this paper, we explore a set of techniques for limiting human motion of upper body gestures to that achievable by a Sarcos humanoid robot located at ATR. We assess the quality of the results by comparing the motion of the human actor to that of the robot, both visually and quantitatively.

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There are numerous applications of VR simulation re-quiring the grasping and manipulation of virtual objects. Standard-use haptic interfaces (e.g. Virtuose 6D, PHANToM) allow only a limited level of realism, as grasping is approximated through a metaphor (e.g. pressing a button for grasping an object). Existing hand exoskeletons have also certain drawbacks (e.g. feedback only for finger flexion, limited finger workspace etc.). The work presented in this paper introdu-ces a hand force exoskeleton that allows full finger flexion and extension and applies bi-directional feed-back. It has 3dof at the index finger and 4 at the thumb. The system is actuated by DC motors and cable transmissions are used. It has been designed for use in conjunction with Virtuose 6D, a commercial 6dof haptic arm, in order to allow the simulation of external forces (gravity, contact reaction forces, etc.).

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Although below-knee prostheses have been commercially available for some time, today’s devices are completely passive, and consequently, their mechanical properties remain fixed with walking speed and terrain. To improve the current performance of below-knee prostheses, we study the feasibility of using the amputee’s residual limb EMG signals to control the ankle position of an active ankle-foot prosthesis. We propose two control schemes to predict the amputee’s in-tended ankle position: a neural network approach and a muscle model approach. We test these approaches using EMG data measured from an amputee for several target ankle movement patterns. We find that both controllers demonstrate the ability to predict desired ankle movement patterns qualitatively. In the cur-rent implementation, the biomimetic EMG-controller demonstrates a smoother and more natural movement pat-tern than that demonstrated by the neural network approach, suggesting that a biolo-gically — motivated,model-based approach may offer certain advantages in the control of active ankle prostheses.

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Biomimetic systems attempt to copy the form or the behavior of biological systems to create efficient machines and processes. Since nature has had millions upon millions of years to perfect these systems it is logical to learn from these systems when designing machines and processes. Another way to use the tools that nature has built is to design machines that specifically incorporate a human into the system. These biologically-incorporated systems extend the capabilities of machines by adding a human component or extend the abilities of humans with the assistance of man-made devices. The interfaces that are used when connecting these human and machine systems together are the human senses. These interface systems can truly be called bio-mimetic systems in that they are designed to respond to, or “mimic”, the reactions and sensations of a biological system, namely the human operator. Various systems currently exist that provide information to the human senses of sight and hearing. Audio and video systems have been perfected over many decades so that it is now possible for a user to wear small devices, such as goggles and earphones, which will allow a user to see and hear various forms of information. Systems exist currently and others are being further developed that interface with a third human sense, the sense of touch. These systems are called Haptic Systems or simply Haptics. The inclusion of haptic systems, such as the ones presented in the following sections, allows for the creation of fully immersive environments that can provide a user with the three major inputs of visual, auditory and haptic information. These systems can be used for virtual reality and telepresence applications. The ability to generate visual, auditory and haptic stimuli makes it possible to accurately generate almost any environment that is desired in a believable and immersive manner.

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This article describes the architecture of the «Museum of Pure Form», a virtual reality system where the user can interact, through the senses of touch and sight, with digital models of 3D art forms and sculptures. Two different realizations of «Museum of Pure Form» systems are currently being developed at PERCRO, Pisa, Italy. In one realization “The Museum of Pure Form” is conceived as a system placed inside several museums and art galleries around Europe and made available to people visiting such institutions. In the second realization the system will be placed and tested inside a CAVE environment. Considerations on technological aspects concerning the implementation of a virtual en-vironment endowed with haptic feedback for cultural heritage applications are reported throughout the paper.

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