A linear-quadratic-Gaussian regulator is proposed for the torque control of flexible robotic joints with built-in torque sensor. The regulator requires the joint-torque sensor information only and features: (1) a Kalman filter that, beside reducing the noise and evaluating the derivative of the torque sensor measure, is able to estimate all the external and internal torques acting on the joint; 2) a controller that optimizes system stability, responsiveness, accuracy and effort. The regulator is implemented on a flexible joint of a rehabilitation exoskeleton. Simulation and experimental results are provided which demonstrate regulator performance and efficacy.

This paper deals with the mechanical design of a novel haptic hand exoskeleton (HE) that allows exerting controlled forces on the fingertip of the index and thumb of the operator. The proposed device includes several design solutions for optimizing the accuracy and mechanical performances. Remote centers of motion mechanisms have been adopted for delocalizing the encumbrance of linkages of the structure away from the operator's fingers. An improved stiffness of the transmission and reduced requirements for the actuators have been achieved thanks to a novel patent pending principle for integrating speed reduction ratio with the transmission system.

We describe the development and evaluation of a large-scale multimodal virtual reality simulation suitable for the visualization of cultural heritage sites and architectural planning. The system is demonstrated with a reconstruction of an ancient Greek temple in Messene that was created as part of a EU funded cultural heritage project (CREATE). The system utilizes a CAVE-like theatre consisting of head-tracked user localization, a haptic interface with two arms, and 3D sound. The haptic interface was coupled with a realistic physics engine allowing users to experience and fully appreciate the effort involved in the construction of architectural components and their changes through the ages. Initial user-based studies were carried out, to evaluate the usability and performance of the system. A simple task of stacking blocks was used to compare errors and timing in a haptics-enabled system with a haptics-disabled system. In addition, a qualitative study of the final system took place while it was installed in a museum.

The global scope of the CREATE project is to develop a mixed-reality framework that enables highly interactive real-time construction and manipulation of photo-realistic, virtual worlds based on real data sources. This framework will be tested and applied to cultural heritage content in an educational context, as well as to the design and review of architectural/urban planning settings. The evaluation of the project is based on a human-centered, constructivist approach to working and learning, with special attention paid to the evaluation of the resulting mixed reality experience. Through this approach, participants in an activity "construct" their own knowledge by testing ideas and concepts based on their prior knowledge and experience, applying these to a new situation, and integrating the new knowledge gained with pre-existing intellectual constructs. CREATE project uses a high degree of interactivity, and includes provision for other senses (haptics and sound). The application developed in CREATE are designed to run on different platforms, and the targeted running systems are SGI and PC driven, with immersive stereo-displays such as a workbench, a ReaCTor (CAVE-like environment), and a wide projection screen.