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Falls are one of the most common causes of accidental injury: approximately, 37.3 million falls requiring medical intervention occur each year. Fall-related injuries may cause disabilities, and in some extreme cases, premature death among older adults, which has a significant impact on health and social care services. In recent years, information and communication technologies (ICT) have helped enhance the autonomy and quality of life of elderly people, and significantly reduced the costs associated with elderly care. We designed and developed an integrated fall detection and prevention ICT service for elderly people, which was based on two wearable smart sensors, called, respectively, WIMU fall detector and WIMU data-logger (Wearable Inertial Measurement Unit, WIMU), their goal was either to detect falls and promptly react in case of fall events, or to quantify fall risk instrumentally. The WIMU fall detector is intended to be worn at the waist level for use during activities of daily living, the WIMU logger is intended for the quantitative assessment of tested individuals during the execution of clinical tests. Both devices provide their service in conjunction with an Android mobile device. The ICT service was developed and tested within the European project I-DONT-FALL (Integrated prevention and Detection sOlutioNs Tailored to the population and risk factors associated with FALLs, funded by EU, action EU CIP-ICT-PSP-2011-5: GA #CIP-297225). Sensor description and preliminary testing results are provided in this paper.

The question whether barometric altimeters can be applied to accurately track human motions is still debated, since their measurement performance are rather poor due to either coarse resolution or drifting behavior problems. As a step toward accurate short-time tracking of changes in height (up to few minutes), we develop a stochastic model that attempts to capture some statistical properties of the barometric altimeter noise. The barometric altimeter noise is decomposed in three components with different physical origin and properties: a deterministic time-varying mean, mainly correlated with global environment changes, and a first-order Gauss-Markov (GM) random process, mainly accounting for short-term, local environment changes, the effects of which are prominent, respectively, for long-time and short-time motion tracking; an uncorrelated random process, mainly due to wideband electronic noise, including quantization noise. Autoregressive-moving average (ARMA) system identification techniques are used to capture the correlation structure of the piecewise stationary GM component, and to estimate its standard deviation, together with the standard deviation of the uncorrelated component. M-point moving average filters used alone or in combination with whitening filters learnt from ARMA model parameters are further tested in few dynamic motion experiments and discussed for their capability of short-time tracking small-amplitude, low-frequency motions.

Researchers have succeeded in partly restoring damaged vestibular functionality in several animal models. Recently, acute interventions have also been demonstrated in human patients. Our previous work on a vestibular implant for humans used predefined stimulation patterns; here we present a research tool that facilitates motion-modulated stimulation. This requires a system that can process gyroscope measurements and send stimulation parameters to a hybrid vestibular-cochlear implant in real-time. To match natural vestibular latencies, the time from sensor input to stimulation output should not exceed 6.5 ms. We describe a system based on National Instrument's CompactRIO platform that can meet this requirement and also offers floating point precision for advanced transfer functions. It is designed for acute clinical interventions, and is sufficiently powerful and flexible to serve as a development platform for evaluating prosthetic control strategies. Amplitude and pulse frequency modulation to predetermined functions or sensor inputs have been validated. The system has been connected to human patients, who each have received a modified MED-EL cochlear implant for vestibular stimulation, and patient tests are ongoing.

In this paper, we present an approach to the online implementation of a gait event detector based on machine learning algorithms. Gait events were detected using a uniaxial gyro that measured the foot instep angular velocity in the sagittal plane to feed a four-state left-right hidden Markov model (HMM). The short-time Viterbi algorithm was used to overcome the limitation of the standard Viterbi algorithm, which does not allow the online decoding of hidden state sequences. Supervised learning of the HMM structure and validation with the leave-one-subject-out validation method were performed using treadmill gait reference data from an optical motion capture system. The four gait events were foot strike, flat foot (FF), heel off (HO), and toe off. The accuracy ranged, on average, from 45 ms (early detection, FF) to 35 ms (late detection, HO); the latency of detection was less than 100 ms for all gait events but the HO, where the probability that it was greater than 100 ms was 25%. Overground walking tests of the HMM-based gait event detector were also successfully performed.

The vestibular system detects rotational velocity and linear acceleration of the head in order to identify body’s spatial orientation. Impairments of these organs induce the subject to spatial disorientation, postural instability, self-motion perception deficits, and chronic disequilibrium. Gaze stabilization performances are usually evaluated by the assessment of the Visual Acuity during head movements. This work introduces a new testing device, named Up-Down Chair (UDC), able to generate full body linear accelerations in the vertical direction. These stimuli can be tuned to mimic those encountered during natural activities. This platform has been designed to serve as an experimental set up to quantify vestibular functions and their relationship to clinical scales. Moreover, the UDC could be used to assess specific testing performance for a vestibular neuroprosthesis.

This study introduces three new robotic platforms aimed at investigating the performance of subjects affected by vestibular diseases while providing i) balance perturbations in horizontal directions while subjects carry out daily motor tasks (SENLY), ii) pure linear vestibular system stimuli in vertical direction (Up-Down Chair) and iii) pure rotational vestibular system stimuli in roll, pitch and yaw directions (Oscillating Chair).

Transverse intrafascicular multichannel electrodes (TIMEs) are polyimide-based microelectrodes, which are potentially very interesting to restore sensorimotor functions in disabled people. By means of microstimulation of the nerve stump of an amputee, it can be possible to manipulate the phantom limb sensation, to provide sensory feedback to upper limb amputees, and to investigate methods of treatment of phantom limb pain. The current insertion procedure of TIMEs is completely done by hand. This makes the task difficult. This paper presents the preliminary results related to the development of a robotic tool to increase the accuracy in electrode placement and reduced size of the working area. The possibility to manage insertion parameters such as force, velocity, and positioning, could decrease the risk of damaging the nervous tissue, improving the coordination, and making placements repeatable. With the aim of solving the issues avbove, we developed a first prototype of a 4DoF multi-axis device. Additional strategies concerning system components and control are discussed. We performed characterization of implantation mechanics to derive mechanical design specifications for the robotic device. Force caracterization of the pig peripheral nerve during penetration of the needle at three velocities (1, 30, 40mm/sec) was executed. Results shown inverse relationship between maximal force and velocities values. The force values extracted varied between 0.081–0.174 N.

The chapter describes a teleoperation system for assisting disabled and elderly people in their lives and work environments. The developed system ASIBOT (assistive robot) is part of the EU 5th FP project MATS (IST 2001-32080). The goal of the project is to come up with a new concept in teleoperated robotics systems that would help people in their daily domestic activities such as eating, drinking, shaving, grooming or simply retrieving objects from shelves or from the floor, etc. The best feature of the ASIBOT system is represented by a snake-like robot arm that is capable of moving around serially from a wall-mounted or table- mounted docking stations. The robot is also able to “jump” to or from a wheelchair. One of the important properties of proprio and teleoperation of assistive robots is the fact that the operator could be at the same time the patient, the user or the target of the task. Due to disability, the operator has limited capability on controlling the master and also considerable delays in closing the teleoperation loop. Depending on the level of the operators disability, different types of HMI are needed to be used. Some HMI are commanded by voice, simple switches or a joystick.

In this paper, we develop a system for which applications in the field of personal navigation are planned. In the current version, the system embodies a Global Positioning System (GPS) receiver and an inertial measurement unit (IMU), composed of two dual-axis accelerometers and one single-axis gyro. The IMU is positioned at a subject's foot instep, and it is intended to produce estimates of some gait parameters, including stride length, stride time, and walking speed. Data from GPS and IMU are managed by a DSP-based control box. The computations performed by the DSP processor allow to detect subsequent foot contacts by a threshold-based method applied to gyro signal, and to reconstruct the trajectory of the foot instep by numerical strapdown integration. Features of human walking dynamics are incorporated in the algorithm to enhance the estimation accuracy against errors due to sensor noise and integration drift. All computations are performed by the DSP processor in real-time conditions. The foot sensor performance is assessed during outdoor level walking trials. The traveled distance estimated by inertial dead-reckoning is compared with the estimate produced by GPS in experimental conditions where GPS can be used as a reference source for accurate absolute positioning. Results show the remarkable accuracy achieved by foot inertial sensing.

This paper reviews a new approach in the area of rehabilitation robotics. The service robot MATS helps disable and elderly people in their day life activities in common living environment like kitchen, bathroom, bedroom, etc. In this way the quality of life of the important part of population improves toward their social integration. This new prototype has new abilities like climb from one wall to another or from the table to the wheelchair, and at the same time to be attached and move with the wheelchair. The robot is totally autonomous and needs only power supply to be operated. This paper presents the distributed software architecture and the concept design of the HMI which handles the robotic system.

In this paper we illustrate the main features of a vision-based 2D localisation system, endowed with the real-time capability of estimating the location of active light-emitting markers disposed on a horizontal plane. The vision-based system revolves around using an inexpensive, off-the-shelf web-camera under computer control: the system is simple to install and operate, yet accurate to a level which is acceptable in a range of applications. Specifically, we describe how we intend to exploit the localisation system in an application whose ultimate goal is to support motor-impaired users in the approach to a specific configuration with their mobility aid, e.g., an electric wheelchair. To serve this application, the vision-based localisation system is integrated in a human-machine-interface, built around an handheld PC, which aims at providing the driver with a "top-view" representation of the scene. In our preliminary experiments, the perceptual enhancement is shown beneficial in increasing the docking accuracy up to few millimeters and tenths of degrees from the "target" configuration.

In this paper we describe a motorised rollator which aims at supporting people with motor impairments while walking and transporting objects. The prototype presented here incorporates a few additional functions, including the force enhancement to the user in the direct control mode, and the ability to follow the user at a distance, with or without collision avoidance, in the follow-me mode. The user input device for the direct control mode is composed of bilateral grips, equipped with strain gage force sensors, whose output signals are used for motor speed control. The follow-me mode is built around a trilateration system based on ultrasonic and infrared sensing technologies; the system activates a user-worn transponder for person tracking. We discuss both the motivations behind the control modes of interest and the technical solutions we have devised for their implementation. The results of some preliminary experiments are also presented and discussed, to show the feasibility of the approach.

The authors describe the notion of a distributed robotic system (DRS) based on instinctive response and cooperation. Two specific aspects of the DRS are investigated in some detail: the self-configuration capabilities and the pattern generation problem. Simulation was used as a tool for dealing with the variety of possible distributions of the DRS, of environmental conditions, and of individual reactions of each robotic unit. Problems associated with communication between robotic units are also addressed. Simulation results demonstrate that communication and cooperation are very effective in enhancing the performance of the DRS during tasks requiring exploration, such as the search for pollutants. >

In this paper, we present bird's-eye (BE) viewer - a sensor-based navigation system intended to assist motor-impaired people driving their mobility aids to a specified goal. The BE-viewer is built around a vision-based 2D localization system based on a monocular image system composed of one web-camera, and endowed with real-time capability of estimating the location of active light-emitting markers. The 2D localization system is integrated in a human-machine-interface, which provides the user with a "top-view" sketch of the current and desired configurations. We introduce a protocol for the functional assessment of the docking procedure, here interpreted as a pursuit tracking task. The protocol allows to characterize how subjects use their resources to achieve a balance between speed, accuracy and control effort, depending on whether the perceptual enhancement by the BE-viewer is available or not. The benefits of the BE-view approach are presented and discussed on preliminary experiments where normal subjects perform docking procedures using a motorized anterior walker.

The problem of developing a sensing system for robots moving in a partially or completely unknown environment is investigated. A model of a generalized sensitive skin based on different types of sensors to be located on the whole surface of a robot is illustrated. A logic and hardware structure of the low-level layer of the skin is proposed to guarantee modularity and consistency of sensory data. A configuration including ultrasonic and infrared proximity sensors was chosen for the implementation of a prototype of the skin. A possible physical layout for obtaining a conformable skin to be used on any kind of robot surface is also presented. Local and general rules for low-level sensory data fusion are defined, and possible improvements of real-time obstacle avoidance path planning strategies are discussed by introducing sensor-based instinctive behaviors. A simulation of a modified potential field-based real-time planner for a mobile robot operating in a partially unknown environments is discussed to demonstrate the feasibility of this approach.

A description is presented of the social organization of societies of cellular mobile units featuring instinctive behavior. Each robotic unit has its own personality and lives independently from the others. Useful tasks are carried out through collaboration rather than by individual effort. The behavior of each unit derives from a subsumption-like control structure, which emphasizes the roles of innate personality, external stimuli, and communication. A number of different robotic personalities are described and techniques of implementing them in real robot units are outlined. The implementation of instinctive behavior is described for the case of a robotic vehicle system (ROBBIE). >

Presents an approach to the implementation of the concept of 'distributed robotic system' (DRS), based on the notions of 'instinctive' response and cooperation. The proposed DRS is composed of cellular robotic units which operate in a constrained unstructured environment and are dedicated to environmental monitoring. This specific application, of potentially wide practical interest, poses a number of constraints to the control of the DRS, which can be solved efficiently by using the proposed approach. >

In this paper, the authors describe a sensing method, called differential compassing, which can be applied to pursue leader/follower behaviors in the field of service robotics. Differential compassing is applied to integrate proximity/range sensing in robot systems, the operation of which can involve a hands-free interaction mode, where the robot (the follower) reacts to the movements of a walking user (the leader), so as to maintain close proximity to him. Differential compassing exploits two compasses, one of them on the leader and the other one on the follower. The simple idea behind this approach is that, if a magnetic disturbance affect the two compasses, one compass will be more influenced than the other, but heading errors may have similar magnitude

Describes an approach to the design of cellular mobile units featured by 'instinctive' behavior and forming collectively a 'society' of robots. Each robotic unit has its own 'personality' and 'lives' independently from the others. The behavior of each unit derives from a 'subsumption-like' control structure, which emphasizes the roles of 'innate personality', external stimuli, and communication. An example of implementation of instinctive behavior in a real robotic vehicle is presented, and a possible application of the proposed approach to the practical case of a robot system for collecting objects is illustrated. >

A portable system is developed to monitor physical activity by acquiring and storing data from body-mounted sensors; a handheld PC is used for managing data acquisition and storage, including radio-transmission to a remote host. An application related to the use of a gyro-accelerometric sensor for determining walking distance is discussed.

The authors describe their approach to the design of redundant proximity sensor systems that are capable of extracting geometrical information about the surrounding environment and perceiving other relevant features of the reflecting objects, e.g. colour. Potential applications of the proposed sensorial systems are in the field of robotics and autonomous mobility.

Service robots are machines designed to work not onlyfor human beings (like the industrial robot) butalso with human beings. In addition to challenging technical problems, the application of service robots in real-life situations requires to address intriguing issues concerning their interactions with humans. We are investigating both types of problems with reference to three different case studies and real research projects: a mobile robot system primarily aimed at the assistance of patients in hospitals and institutions (the “URMAD” project); a mobile robot system for the assistance to the disabled and the elderly at home (the “MOVAID” project); and a wheelchair incorporating a robot arm (the “IMMEDIATE” project). The paper discusses the design of the three robotic systems as well as their practical implementation and preliminary experimental results. Finally, the paper addresses recent results which could lead to the implementation of cybernetic prostheses, that is devices which would ultimately allow to achieve real intimate physical symbiosis between human beings and artificial robotic devices.