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Background and objectives: Feedback plays a crucial role for using brain computer interface systems. This paper proposes the use of vibration-evoked kinaesthetic illusions as part of a novel multisensory feedback for a motor imagery (MI)-based BCI and investigates its contributions in terms of BCI performance and electroencephalographic (EEG) correlates. Methods: sixteen subjects performed two different right arm MI-BCI sessions: with the visual feedback only and with both visual and vibration-evoked kinaesthetic feedback, conveyed by the stimulation of the biceps brachi tendon. In both conditions, the sensory feedback was driven by the MI-BCI. The rich and more natural multisensory feedback was expected to facilitate the execution of MI, and thus to improve the performance of the BCI. The EEG correlates of the proposed feedback were also investigated with and without the performing of MI. Results and Conclusions: the contribution of vibration-evoked kinaesthetic feedback led to statistically higher BCI performance (Anova, F(1,14) = 18.1, p < .01) and more stable EEG event-related-desynchronization. Obtained results suggest promising application of the proposed method in neuro-rehabilitation scenarios: the advantage of an improved usability could make the MI-BCIs more applicable for those patients having difficulties in performing kinaesthetic imagery.

This paper presents a novel electromyography (EMG)-driven hand exoskeleton for bilateral rehabilitation of grasping in stroke. The developed hand exoskeleton was designed with two distinctive features: (a) kinematics with intrinsic adaptability to patient's hand size, and (b) free-palm and free-fingertip design, preserving the residual sensory perceptual capability of touch during assistance in grasping of real objects. In the envisaged bilateral training strategy, the patient's non paretic hand acted as guidance for the paretic hand in grasping tasks. Grasping force exerted by the non paretic hand was estimated in real-time from EMG signals, and then replicated as robotic assistance for the paretic hand by means of the hand-exoskeleton. Estimation of the grasping force through EMG allowed to perform rehabilitation exercises with any, non sensorized, graspable objects. This paper presents the system design, development, and experimental evaluation. Experiments were performed within a group of six healthy subjects and two chronic stroke patients, executing robotic-assisted grasping tasks. Results related to performance in estimation and modulation of the robotic assistance, and to the outcomes of the pilot rehabilitation sessions with stroke patients, positively support validity of the proposed approach for application in stroke rehabilitation.

Electric rail vehicles are driven by the current collected from the electrical lines of the railway catenary system. For this purpose, trains are equipped with a current collector (the pantograph) that comes in contact with the wires by means of a pair of carbon strips. The sliding movement along the wires subjects the carbon strips to wear and damage so that frequent inspection is essential to ensure the train and catenary safety. In this paper we describe an automatic visual inspection system, made of a 3D laser scanner and a 2D high resolution camera, which is able to automatically determine the health state of the railway contact strips thanks to a sophisticated data processing tool. The system collects color and geometrics information on the carbon strips and performs several automated assessments both on the 3D and 2D data. For each test, the system provides an index and decides between three different levels of wear (low, medium, high) to support the human operator in inspection and maintenance decisions. Experimental results reveal the effectiveness of the system, comparing the human judgment with the automated analysis.

This article introduces and describes an electrically powered full-body (FB) exoskeleton, called the body extender (BE), intended as a research platform for the study of the transport and handling of heavy loads up to 50 kg, with one hand at worst-load conditions (WLCs). The machine features a 22-degrees-of-freedom (DoF) quasi-anthropomorphic kinematic scheme and a modular hardware/software architecture that made it possible to manage the complexity of the system design. Besides providing a context and some general guidelines, which have driven the design of the BE, this article presents the hardware and software developments that have been achieved and implemented in the machine. The experimental results are shown that prove the functionalities of the BE in common operating conditions such as walking, squatting, and handling loads. The one-of-a-kind system demonstrates, in relevant laboratory settings, the feasibility of a complex, electrically powered full-body exoskeleton with such a target payload.

This paper presents the work related to the 3D reconstruction of the scene depicted in the famous Piero della Francesca's fresco “The Resurrection”. The work has presented many challenges due to the fact that deliberate alterations to a mathematically correct perspective were introduced by the artist in order to visibly underline the contrast between the divine plane (Christ resurrected) and the human plane (a group of soldiers witnessing the scene). The reconstructed 3D model has been used in an interactive application enabling the virtual visit of the scene as seen from relevant viewpoints corresponding to the different perspectives and to details of the depicted figures. The application also allows to change in real-time the lighting conditions of the scene in order to compare the virtual illumination with the one present in the fresco so as to illustrate possible alternatives about the debated original collocation of the artwork.

This article introduces the design and the experimental validation of the Trackhold, a novel mechanical motion-tracker for upper limb physical rehabilitation. The Trackhold is based on a passively balanced mechanism that can approximately relieve the weight of the patient’s arm regardless of the position. The system features a novel kinematic architecture with large workspace and custom developed joint sensors providing accurate real-time measure of the upper limb posture. The design approach of the device, which went through kinetostatic and dynamic analyses, is presented and details on the employed mechatronic solutions are provided. A prototype of the Trackhold has been fabricated and functionally validated.

Contemporary museums are much more than places devoted to the placement and the exhibition of collections and artworks; indeed, they are nowadays considered as a privileged means for communication and play a central role in making culture accessible to the mass audience. One of the keys to approach the general public is the use of new technologies and novel interaction paradigms. These means, which bring with them an undeniable appeal, allow curators to modulate the cultural proposal by structuring different courses for different user profiles. Immersive Virtual reality (VR) is probably one of the most appealing and potentially effective technologies to serve this purpose; nevertheless, it is still quite uncommon to find immersive installations in museums. Starting from our 10 years’ experience in this topic, and following an in-depth survey about these technologies and their use in cultural contexts, we propose a classification of VR installations, specifically oriented to cultural heritage applications, based on their features in terms of interaction and immersion. On the basis of this classification, aiming to provide a tool for framing VR systems which would hopefully suggest indications related to costs, usability and quality of the sensorial experience, we analyze a series of live examples of which we point out strengths and weak points. We then summarize the current state and the very next future, identifying the major issues that prevent these technologies from being actually widespread, and outline proposals for a more pervasive and effective use of Immersive VR for cultural purposes.

Relocation is the process of determining the pose of a mobile robot with respect to a world-fixed reference frame with no assumption about its previous states. This capability is often needed in long-lasting autonomous navigation, in the case the localization process fails and the robot has to initialize again its own pose estimation. The relocation procedure presented in this paper is an extension of the algorithm presented by Lim and Leonard [10] and is basically a solution to the problem of searching a correspondence between information gathered from sensors and information available from the map, aimed at the initialization of a starting localization process. The effectiveness of the relocation procedure is demonstrated through a number of experiments, clearly showing the robustness of the method.

Wearable robots, like prostheses, active orthoses and exoskeletons for human performance augmentations, need a new breed of actuators, capable of exhibiting a large number of desirable features, ranging from high power/torque density, high efficiency, zero backlash and low noise, to low reflected mechanical impedance, high bandwidth and accuracy. Even if it is quite evident that to fully meet these requirements new basic actuation principles have to be investigated and developed in the long term, there is still scope now to innovate the field by combining mature components into new actuation schemes. This paper reports the development and experimental evaluation of an innovative actuator, expressly conceived as an actuation module for a fully powered whole-body exoskeleton, intended for material handling. The main design objective has been the enhancement of the torque density and the mechanical efficiency with respect to existing solutions. The device has shown impressive performances, being able to exer...

It is well known that the application of advanced nonlinear control techniques enable more efficient and precise tracking than linear ones in real models. However, for some critical applications nonlinear schemes are not an option but a requirement, for instance for exoskeleton robots wherein human is wearing the robot and the human is tightly coupled to the powered mechanical linkage. In this paper, we deal with the nonlinear control design of an exoskeleton performing arm rehabilitation on patients with poor neural and motor capabilities. Since this fixed frame man–forearm light exoskeleton presents unknown coupling perturbations, which can neither be neglected nor modeled, a robust and fast controller is desired. To this end, a chattering-free second order sliding mode nonlinear controller is proposed. The closed-loop guarantees fast and robust tracking, whilst rejecting unmodeled bounded dynamics like nonlinear friction and user perturbations. The performance of the closed loop system using Light Exoskeleton renders arm rehabilitation subject to complex trajectories patterns on the basis of the minimum–jerk criterion. Preliminary experimental results show the functionality and validity of the proposed system.

This paper presents a haptic system that is conceived to support the design process of a class of products or services in order to make them more accessible to people affected by hand tremor diseases. The main aim is to foster the designer empathy allowing her/him to directly feel the effect of the impairment in first person. Specifically, a desktop haptic device is employed to induce a programmable hand-tremor, that is typically observed in people affected by some kind of neurological diseases, on healthy subjects (i.e., the designers). The developed tool is based on a wrist-attached haptic interface with a workspace that is comparable to that of the arm of the user. Such device is able to exert controlled forces on the user's wrist and induces a hand-tremor whose frequency and amplitude are correlated with those measured on impaired people. The control of the device is based on a custom trajectory-tracking algorithm that takes as input tremor signals that are acquired on patients using an optical motion tracking system. In this paper, we present the employed haptic system, the structure of the control system and the experimental validation of the controller done through the acquisition of data on six patients affected by Parkinson's disease.

In this paper we propose a full upper limb exoskeleton for motor rehabilitation of reaching, grasping and releasing in post-stroke patients. The presented system takes into account the hand pre-shaping for object affordability and it is driven by patient's intentional control through a self-paced asynchronous Motor Imagery based Brain Computer Interface (MI-BCI). The developed antropomorphic eight DoFs exoskeleton (two DoFs for the hand, two for the wrist and four for the arm) allows full support of the manipulation activity at the level of single upper limb joint. In this study, we show the feasibility of the proposed system through experimental rehabilitation sessions conducted with three chronic post-stroke patients. Results show the potential of the proposed system for being introduced in a rehabilitation protocol.

This paper analyzes the design of a force‐based impedance control for a haptic interface system characterized by a parallel kinematics. By exploiting the features of parallel mechanisms, which perform better than the serial ones in terms of dynamic performance, stiffness and position accuracy, and by implementing a closed‐loop force control, the transparency of a haptic master system and the fidelity of resultant force feedback can be consistently improved. Issues for design and control as well as aspects of performance evaluation of haptic interfaces are treated within the paper and some results of the experimental characterization of a haptic interface are presented.

In order to make a simulation more realistic, motion base simulators provide users with inertial cues, exerting linear accelerations and angular rates on the mock-up vehicle, in addition to the mor...

Visitors to museums are usually not allowed to touch works of art, which means significant restrictions in the experience of art for visually impaired people. A European research project (PURE- FORM), coordinated by PERCRO in Pisa, Italy, indicates a new option. It aims to make possible manual exploration of virtual 3D copies of works of art via a haptic display developed within the project. A selection of statues has been digitized, and virtual 3D copies of them made available for touching. The final goal is that a virtual library of statues will be created that is accessible at all museums having the nec- essary equipment.

The paper describes the multimedia museum installation realized on the occasion of the restoration of the Polyptych of Simone Martini, introducing objectives in terms of communication, fruition and documentation, presenting design and architectural solutions, and discussing the obtained results against the set objectives, demonstrating also the adaptability of the developed concept to other contexts.

In the present paper we introduce a novel wireless system capable of simultaneously track and monitor the motion of the body and the associated muscular stress. The device provides with an array of four inertial and magnetic measurement units combined with up to 32 independent high sensitivity ADC channels. An embedded computing system does allow the high speed (4 KHz) EMG acquisition and filtering, combined with (100Hz) motion reconstruction and relevant features (20Hz) detection. The device connects to any receiving host using a portable server architecture and an extensible computing system which uses a web interface and a plugin architecture based on shared library. The device has been conceived to monitor body activities in application on-the-go, where the use of wired devices is not suitable and the need for a strict synchronizations among the motion reconstruction and the myo-electric signals is fundamental. In what follows we will describe the general architecture of the system, the embedded algorithms for motion and EMG reconstruction and the software architecture of the host system.

The problem of gravity balancing of robotic systems has been investigated for a long time. A big amount of different designs has been developed so far, but with several limitations: applicability only to planar kinematics or some particular spatial ones, encumbrance and reduced workspace of the robot, complication of both theoretical and practical implementation. This chapter deepens a new simple technique for gravity balancing any spatial serial manipulator with rotational joints, using a number of springs less or equal to the number of degrees of freedom of the manipulator. Then, such technique is extended to a concept of actuation for robotic systems. Given a robotic manipulator and a force to exert at the level of the end effector, there is no energy consumption regardless of the configuration of the system (like in passive systems), as long as magnitude and orientation of the required force are fixed. Changes in magnitude and/or orientation of the exerted force require some energy to be achieved (like in active systems). Such combined features make an hybrid system with several benefits: low energy consumptions, simplified control and intrinsic safety of the system, with wide prospects in robotics.

The combination of robotics and virtual reality seems promising for the rehabilitation of the upper limb by promoting intensive training on specific deficits with motor control and multimodal feedback in engaging game-like scenarios. In this paper we present the integration of a robotic system and virtual reality applications for the orthopedic rehabilitation of the arm, in terms of strengthening training and motion recovery. The system simulates the upper limb of the patient and their actions, and allows exhaustive exercising and motor control, giving visuomotor and haptic feedback and trajectory positioning guidance. The system allows assign specific tasks to perform within the virtual environments and aids to evaluate the mobility condition of the patient, to personalize the difficulty level of the therapy and provides kineseologic measures of the patient evolution. We present the results of a preliminary clinical assessment we are carried out on three patients in order to assess the usability and acceptance of the system.

This paper outlines the design and the development of a novel robotic hand exoskeleton (HE) conceived for haptic interaction in the context of virtual reality (VR) and teleoperation (TO) applications. The device allows exerting controlled forces on fingertips of the index and thumb of the operator. The new exoskeleton features several design solutions adopted with the aim of optimizing force accuracy and resolution. The use of remote centers of motion mechanisms allows achieving a compact and lightweight design. An improved stiffness of the transmission and reduced requirements for the electromechanical actuators are obtained thanks to a novel principle for integrating speed reduction into torque transmission systems. A custom designed force sensor and integrated electronics are employed to further improve performances. The electromechanical design of the device and the experimental characterization are presented.

This work presents the development and the preliminary experimental assessment of a novel EMG-driven robotic hand exoskeleton for bilateral active training of grasp motion in stroke. The system allows to control the grasping force required to lift a real object with an impaired hand, through the active guidance provided by a hand active exoskeleton, whose force is modulated by the EMG readings acquired on the opposite unimpaired arm. To estimate the grasping force, the system makes use of surface EMG recordings during grasping, developed on the opposite unimpaired arm, and of a neural network to classify the information. The design, integration and experimental characterization of the system during the grasp of two cylindrical objects is presented. The experimental results show that an optimal force tracking of the interaction force with the object can be achieved.

Thanks to their large power densities, low costs and shock-insensitivity, Dielectric Elastomers (DE) seem to be a promising technology for the implementation of light and compact force-feedback devices such as, for instance, haptic interfaces. Nonetheless, the development of these kinds of DE-based systems is not trivial owing to the relevant dissipative phenomena that affect the DE when subjected to rapidly changing deformations. In this context, the present paper addresses the development of a force feedback controller for an agonist-antagonist linear actuator composed of a couple of conically-shaped DE films and a compliant mechanism behaving as a negative-rate bias spring. The actuator is firstly modeled accounting for the viscohyperelastic nature of the DE material. The model is then linearized and employed for the design of a force controller. The controller employs a position sensor, which determines the actuator configuration, and a force sensor, which measures the interaction force that the actuator exchanges with the environment. In addition, an optimum full-state observer is also implemented, which enables both accurate estimation of the time-dependent behavior of the elastomeric material and adequate suppression of the sensor measurement noise. Preliminary experimental results are provided to validate the proposed actuator-controller architecture

This paper presents the results of the evaluation training performed in a group of chronic stroke patients with Light-Exoskeleton device. The rehabilitation treatment included passive, assisted and active reaching exercises based on a impedance control strategy with gain modulated by the patient's ability to perform the task. The effects of training were assessed both by means of clinical evaluation in terms of Fugl-Meyer and Modified Ashworth assessment scales, and of functional evaluation, by means of Bimanual Activity test. Moreover, at each session an automatic assessment of performance was made through two robotic measures (task time and smoothness of movement), and these were analysed in term of correlation with the outcome of functional evaluation. Interestingly we found a significant improvement of both clinical and functional evaluation, and that the automatic assessment performed by the robot in terms of smoothness represents a strong predictor of transfer of functional ability to activity of every day life. The high correlation observed between functional outcome and robotic measures suggest the last ones can provide a rapid and useful feedback about the patient's recovery progress, in addition to the pre- and post-clinical and functional measurements.

This paper presents the development of an interaction-torque control architecture for a rehabilitation exoskeleton (RehabExos) with flexible joints equipped with internal torque sensors. The architecture consists of an outer control loop, which is based on the kineto-statics of the RehabExos, and on four identical-independent inner full-state joint-torque controllers (IJTFC). The considered IJTFC demonstrate good stability, responsiveness and accuracy in tracking the desired torques generated by the outer controller. Comparison with other control strategies available from the literature is shown via analytical and experimental results, which highlight the improved performances of the proposed IJTFC method in controlling the RehabExos robot.

This paper presents a novel approach to train how to juggle using a sensor system based on one of the most commercial, sophisticated and accessible input devices, the Wii Remote controller. This platform, particularly its infrared camera, is used to develop a real-time sensor system for hand motion tracking and fit it into a virtual reality interface. The quality of our algorithm was tested through this 3D virtual interface, which has the finality to give the user visual feedback of his/her hand positions, and created for the user the sensation of juggling.

This paper presents the preliminary results of the project BRAVO (Brain computer interfaces for Robotic enhanced Action in Visuo-motOr tasks). The objective of this project is to define a new approach to the development of assistive and rehabilitative robots for motor impaired users to perform complex visuomotor tasks that require a sequence of reaches, grasps and manipulations of objects. BRAVO aims at developing new robotic interfaces and HW/SW architectures for rehabilitation and regain/restoration of motor function in patients with upper limb sensorimotor impairment through extensive rehabilitation therapy and active assistance in the execution of Activities of Daily Living. The final system developed within this project will include a robotic arm exoskeleton and a hand orthosis that will be integrated together for providing force assistance. The main novelty that BRAVO introduces is the control of the robotic assistive device through the active prediction of intention/action. The system will actually integrate the information about the movement carried out by the user with a prediction of the performed action through an interpretation of current gaze of the user (measured through eye-tracking), brain activation (measured through BCI) and force sensor measurements.

The PERCRO laboratory of Scuola Superiore Sant'Anna has recently completed the development and functional assessment of the Body Extender (BE) system, an advanced wearable robot expressly conceived for augmenting the human strength for handling of heavy materials in unstructured environment. The system is composed by four robotic limbs with anthropomorphic kinematics and has a total of 22 independently actuated degrees of freedom. The leg locomotion and the force servo-amplification allow operations in environments that are hardly accessible by the conventional handling systems preserving the force sensibility during the manipulative tasks. Possible applications are handling of military materials in narrow spaces, rescuing of victims in natural and human provoked disasters and handling of heavy parts in the manufacturing of large products. The paper reports the system specifications taken as a reference for the design, the criteria and verification methods, the architectural solutions used for the implementation of mechanics, electronic and control components and the results of the preliminary experimental assessment.

Several manipulators or exoskeleton are characterized by having a concave workspace in the operational space due to mechanical limits. This article proposes an online trajectory planning method for performing visually guided assisted reaching through a rehabilitation robotic exoskeleton, the L-Exos, in its concave workspace. To evalute the proposed methodology in a rehabilitation application, we set-up a computer vision based system that can automatically identify target objects in the workspace and generate a robot assisted movement to reach them through the L-Exos.

In the next future Virtual Reality technologies will allow the dramatic reduction of the development time of “soft products”, like textiles, household papers and car interiors, making possible the subjective assessment of their fine mechanical properties, through the realistic rendering of the visual and haptic sensations arising during the physical interaction of these objects with the human hand. This paper deals with the development issues of a complete haptic interface, able to allow the simultaneous generation on the human hand of both kinesthetic and tactile stimulations. The device has been conceived for the haptic rendering of textiles and is composed by a multipoint force feedback device, in charge of generating arbitrary resultant forces on the index and thumb fingertips, and by two independent tactile arrays, in charge of generating time and spatially distributed tactile stimulations on the palmar surface of the two fingertips. After a brief discussion of the reference configuration selected for the whole haptic interface, it has been reported the functionalities, architecture and performances of the realized force feedback device, hosting the tactile arrays. Then the papers focuses on the development issues of a suitable tactile array, discussing its general requirements and the selected architecture. Finally the technical solutions selected for the implementation of its main components and their experimental evaluations are reported.Copyright © 2011 by ASME

This paper presents the results of the design, implementation and evaluation of a platform for rowing training in Virtual Reality called SPRINT. The paper discusses how various aspects of the rowing skill can be analyzed and trained over a single common methodology and system platform. The result is a vision for new directions in the domain of sport training with Virtual Reality.

This paper describes the design, the preliminary evaluation and proposes a control strategy of a novel distributed tactile transducer for finger tip stimulation. The presented study has been conducted for the realization of a compact tactile device aiming at integration with a kinesthetic feedback systems. The transducer is a 5x6 array based on custom electromechanical mini-solenoid designed and optimized for reduced encumbrance and lightweight. The realized actuator has a diameter of 2.4mm and is capable of delivering a maximum force of 73mN. In the first section we present the electro-mechanical design, the optimization and the first experimental test of a prototype for the new transducer. In the second section we show the electronic design and a strategy for controlling arrays of transducers with a reduced number of connectors. This principle is based on active matrix addressing of LCD displays.

Artistic handicraft is considered to all intents and purposes an important part of Cultural Heritage. The idea of creating a multimedia platform to communicate the tradition of artistic handicraft in Lucchesia (Tuscany, Italy) was born in order to preserve the memory of activities which have contributed in defining this region in terms of history, culture, peculiarity and quality of its products. The town of Pietrasanta, in particular, is well renowned for its artisans, who have been handing down ancient practices for ages, especially in the workmanship of marble and bronze. Our project aims at the valorisation and the communication of the bronze “investment casting” ancient technique through a 3D virtual interactive platform. This platform offers therefore a contribution to preserve this heritage and its memory, by means of a virtual experience inside the processes and the places where bronze sculptures are made. Users can follow from the beginning how such an artwork is created, dwelling on each step of the creation process and analyzing in details its main points.

The distinguishing features of active exoskeletons are the capability of guiding arm movement at the level of the full kinematic chain of the human arm, and training full 3D spatial movements. We have specifically developed a PD sliding mode control for upper limb rehabilitation with gain scheduling for providing "assistance as needed", according to the force capability of the patient, and an automatic measurement of the impaired arm joint torques, to evaluate the hypertonia associated to the movement during the execution of the training exercise. Two different training tasks in Virtual Reality were devised, that make use of the above control, and allow to make a performance based evaluation of patient's motor status. The PERCRO L-Exos (Light-Exoskeleton) was used to evaluate the proposed algorithms and training exercises in two clinical case studies of patients with chronic stroke, that performed 6 weeks of robotic assisted training. Clinical evaluation (Fugl-Meyer Scale, Modified Ashworth Scale, Bimanual Activity Test) was conducted before and after treatment and compared to the scores and the quantitative indices, such as task time, position/joint error and resistance torques, associated to the training exercises.

Advanced robotics needs a new breed of actuators, capable to exhibit a large number of desirable features, ranging from high power/torque density, high efficiency, zero backlash and low noise, to low reflected mechanical impedance, high bandwidth and accuracy. Even if it is quite evident that to fully match these requirements new basic actuation principles have to be investigated and developed in the long term, there is still scope now for innovating the field by combining mature components into new actuation schemes. This paper reports the development and the experimental evaluation of a new actuator, aiming at improving the torque density and the mechanical efficiency. The device has shown impressive performances being able to exert up to 500Nm continuous torque and 800Nm peak torque with 85% mechanical efficiency and zero backlash, up to 60°/s maximum output speed for a total weight of just 6Kg, comprising the structural case covering the internal mechanics. The actuator has been expressly conceived as an actuation module to be integrated in a fully powered whole body exoskeleton intended for material handling in tight and unstructured environments (see Fig.1).

Technological and fundamental developments in robotics can emerge from various sources like publications or international research plans. Among the various sources of analysis, patents results valuable in expressing the efforts performed both by companies and research institutions. This work takes the occasion of the fifty years of robotics for presenting an analysis and visualization of trends in robotics by means of patent mining. This work focuses, in particular, on the domains of rehabilitation and surgical robotics. The discussed methodology highlights the role of haptic interfaces in these fields and the relationships between relevant companies.

Rehabilitation robotics applications and their developments have been spreading out as consequences of the actual needs in the human activities of daily living (ADL). Exoskeletons for rehabilitation are one of them, whose intrinsic characteristics are quite useful for applications where repetitive, robustness and accurate performance are a must. As a part of robotic-mediated-rehabilitation programme into the worldwide, the exoskeletons are trying to improve the ADL of disable people through the fusion of several disciplines that lets to expand the capabilities of wearing a powered robotic exoskeletal device for rehabilitation tasks. This fact deserves to present this contribution from a general scope point of view, i.e., the technologies integration and its associated knowledge. So far, the Light-Exoskeleton which is intended for human arm rehabilitation in post-stroke patients is introduced. Preliminary experimental results as well as the involved stages about the system show the capabilities of using a robotic-constrained-rehabilitation for human arm.

Robotic interfaces combined with virtual reality provide an unparalleled platform for cognition research. Using a combination of design strategy, trend analysis and immersive virtual reality systems, our intent has been to design and build the "ultimate" interactive aesthetic experience. This paper discusses the creative process and the preliminary results of this engineering research.

The required tasks in fixed-base exoskeletons demand a fast position/force controller; yet robust against unknown disturbances due to the application itself is tightly coupled with a human in a wide range of operational conditions, which give rise to human-exoskeleton interaction dynamics, high nonlinear uncertain exoskeleton dynamics, noisy sensors and other parametric uncertainties, such as environmental contacts. These factors do not allow to account on a precise dynamical model, thus model-based (regressor-based) controllers are difficult to implement. This paper deals with a regressor-free smooth PID-like fast force/position controller which guarantees finite-time convergence within second order sliding modes, thus ensuring inherent robustness. Experimental platform allows assessing its performance for rehabilitation tasks, which validates its functionality in practical implementation.

This paper deals with the development of a novel exoskeleton for the robotic rehabilitation of upper extremities. The system is based on modular custom-designed actuation groups implementing high reduction ratios and redundant position measurement for securing patient safety, and joint torque sensing for guaranteeing system performance and providing application flexibility. Experimental results of the special component prototypes are reported which confirm the validity of the developed actuation groups and the potentials of the proposed exoskeleton architecture.

Several studies have shown that the optic flow serves as a tool for navigation for animals. Flying insects use it to follow paths and avoid obstacles, while in primates it represents an additional input that can improve navigational performance. A neuroinspired architecture for optic flow calculation and decision making, based on the cortical organization of the human brain, has been developed and successfully used as a novel control system for a mobile robot. Navigation in a corridor and obstacle avoidance are achieved relying only on the optic flow. Moreover, the presence of the optic flow improves the performance of the robot in target reaching and obstacle avoidance tasks in a virtual environment, affecting its trajectories as shown by experiments with human subjects.

Human walking gait (HWG) involves concurrently complex aspects of control, signal conditioning and processing, motion capture and biomechanical analysis as well as bioelectronic instrumentation and robot control. To merge some of these concepts into a unique framework, in this paper, a computational mechatronics scheme is proposed for the analysis and synthesis of HWG based on a seven-link sagittal rigid dynamical biped robot in closed-loop with an advanced force/position/velocity model-free position-force controller. Desired trajectories come from real human motion data: Lower-limbs walking gaits kinematic patterns are captured with a human motion Vicon ® tracker system, including landing point, and impact (ground reaction) forces are obtained from femur/tibial muscles via EMG. A criteria is established to map such signals into a 7 DoF workspace of the dynamical biped robot. Fast dynamical tracking is achieved under real HWG patters, which provides greater insight into the design and control process of humanoid robotic biped locomotion.

This paper presents a vibrotactile methodology for a rowing training system. Since hands' trajectories are fundamental in the rowing gesture, it is completely necessary to search and develop new technologies and techniques that can interact and help the user to perform a better movement. These methodologies must be as natural as possible in order to guarantee the transparency in the feedback of the system. Therefore this paper presents an analysis of visual, visual-tactile and tactile training strategies to understand the importance in the order and the period of time when each one is applied. Data analysis shows the importance of combining visual and tactile feedbacks to obtain the best results in the improvements of the user skills.

In this paper, we present the design of a new fMRI compatible haptic interface with 3DOFs, based on electrical DC actuation, for the study of brain mechanisms of human motor control. In order to evaluate the validity of the proposed solution, we performed some preliminary experiments with a single degree of freedom device to test the compatibility with the fMRI environment. The 1DOF design was extended to the implementation of a 3DOFs parallel manipulator with 3UPU kinematics. Due to the dimensional constraints imposed by the fMRI environment, the choice of the dimensions and of the adopted mechanical solution was a result of an optimization process, that is presented in this work. Reachable workspace, kinematic isotropy, end-point stiffness, minimum force and translational clearance were studied in different configurations to select the stroke of the prismatic joint and the radius difference between the moving platform and the base. A further optimization of the mechanical design was then conducted in order to reduce the torque requested to the actuators for gravity compensation and consequently improve the performance of the manipulator. The final design resulted in a system capable of satisfying all the environment and user requirements.

Any teleoperation system involving two distant devices is affected by communication delay due to the physical gap between the devices. Several approaches based on wave variables have already been proposed to deal with time-varying delay. However, these approaches are too conservative resulting in high degradation from the constant time delay case. In this paper, we propose a new control scheme for bilateral teleoperation under time-varying communication delay entirely developed in the wave variables domain. The proposed method minimizes the performance degradation from the constant time delay case. Experimental results show the validity of the proposed scheme.

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.

This paper presents the integration of multimodal technologies to measure and transmit different variables and stimuli involved in the human motion analysis, both for the training and for the transfer of users skills achieved by means of a mechatronic rowing platform. Although the mechanical design is the core of this project, this paper describes the integration and interaction of two multimodal systems (the human being and the rowing platform). These systems works together using different sensors and methodologies directly integrated to the human body to obtain detailed information related to the synchronization and correlation among the trajectories, Proximal distance coupling, velocities, muscular activation and muscular force, transversal force in the oars and head position acquired through digital image processing and machine learning techniques. This information is evaluated and used in the rendering section through audio-tactile stimuli for the acceleration learning process

This paper presents three haptic-based virtual applications for the undergoing rehabilitation of upper-limb post stroke patients. The three exercises are developed for their use on the multi-modal interface so-called Bimanual Haptic Desktop System (BHDS), which integrates the haptic functionalities and Video Display Terminal (VDT) within the work-plane of a desk. Firstly, two basic exercises, tracking task and lifting task, are carried out for the recovery of basic arm motion-coordination skills and steadiness of patients' upper-limb. Secondly, a video-game-like exercise, catching task, is developed to compare online the performance of healthy upper-limb with impaired ones wherein hand-eye coordination exercise of the patient is included. To this end, the proposed exercises provide to patients the potential methods to train their post-stroke upper-limbs malfunctions while reporting the quantitative parameters obtained to evaluate the improvement of patients recovery. Experimental results of a preliminary evaluation on healthy subjects are then reported and discussed to visualize in near future a pilot medical trials of the system on impaired people.

The analysis, synthesis and mechanical design of a wearable biomechanical device for treating the club-foot children malformation is presented in this paper. This system serves as non-invasive alternative method for correcting this congenital malformation in 0-1 year-old children. Robot kinematics and constrained Euler-Lagrange dynamics tools are employed to analyse this malformation, altogether with a quasi-static computational method, and to asses the normal children feet, in order to design a robotic prototype. The 8-months clinical case presented in this paper establishes a preliminary club-foot correction angle of 90%, without typical patient complains, such as those coming from conventional methods, either because of uneasiness and unrest of long-time cast or invasive clinical surgery. The proposed passive noninvasive robotic prototype allows to analyse and to assess the real progress over time and spatial coordinates, which record real data of the betterment of the club-foot malformation.