Loredana Zollo - Profile on Academia.edu (original) (raw)
Papers by Loredana Zollo
Frontiers in Bioengineering and Biotechnology, Nov 10, 2022
The clinical assessment of the human hand is typically conducted through questionnaires or tests ... more The clinical assessment of the human hand is typically conducted through questionnaires or tests that include objective (e.g., time) and subjective (e.g., grasp quality) outcome measures. However, there are other important indicators that should be considered to quantify grasp and movement quality in addition to the time needed by a subject to execute a task, and this is essential for human and artificial hands that attempt to replicate the human hand properties. The correct estimation of hand kinematics is fundamental for computing these indicators with high fidelity, and a technical background is typically required to perform this analysis. In addition, to understand human motor control strategies as well as to replicate them on artificial devices, postural synergies were widely explored in recent years. Synergies should be analyzed not only to investigate possible modifications due to musculoskeletal and/or neuromuscular disorders, but also to test biomimetic hands. The aim of this work is to present an open source toolbox to perform all-in-one kinematic analysis and clinical assessment of the hand, as well as to perform postural synergies extraction. In the example provided in this work, the tool takes as input the position of 28 retroreflective markers with a diameter of 6 mm, positioned on specific anatomical landmarks of the hand and recorded with an optoelectronic motion capture system, and automatically performs 1) hand kinematic analysis (i.e., computation of 23 joint angles); 2) clinical assessment, by computing indicators that allow quantifying movement efficiency (Peak Grip Aperture), smoothness (Normalized Dimensionless Jerk Grasp Aperture) and speed (Peak Velocity of Grasp Aperture), planning capabilities (Time to Peak Grip Aperture), spatial posture (Wrist and Finger Joint Angles) and grasp stability (Posture of Hand Finger Joints), and 3) postural synergies extraction and analysis through the Pareto, Scree and Loadings plots. Two examples are described to demonstrate the applicability of the toolbox: the first one aiming at performing a clinical assessment of a volunteer and the second one aiming at extracting and analyzing the volunteer's postural synergies. The tool allows calculating joint angles with high accuracy (reconstruction errors below 4 mm and 3.2 mm for the fingers and wrist respectively) and automatically performing clinical assessment and postural synergies extraction. Results can be visually inspected, and data can be saved for any desired post processing analysis. Custom-made protocols to extract joint angles, based on different markersets,
Frontiers in Bioengineering and Biotechnology, Dec 1, 2022
The lack of sensory feedback represents one of the main drawbacks of commercial upper limb prosth... more The lack of sensory feedback represents one of the main drawbacks of commercial upper limb prosthesis. Transcranial Focused Ultrasound Stimulation (tFUS) seems to be a valid non-invasive technique for restoring sensory feedback allowing to deliver acoustic energy to cortical sensory areas with high spatial resolution and depth penetration. This paper aims at studying in simulation the use of tFUS on cortical sensory areas to evaluate its effects in terms of latency ad firing rate of the cells response, for understanding if these parameters influence the safety and the efficacy of the stimulation. In this paper, in order to study the propagation of the ultrasound wave from the transducer to the cortical cells, a multiscale approach was implemented by building a macroscopic model, which estimates the pressure profile in a simplified 2D human head geometry, and coupling it with the SONIC microscale model, that describes the electrical behaviour of a cortical neuron. The influence of the stimulation parameters and of the skull thickness on the latency and the firing rate are evaluated and the obtained behaviour is linked to the sensory response obtained on human subjects. Results have shown that slight changes in the transducer position should not affect the efficacy of the stimulation; however, high skull thickness leads to lower cells activation. These results will be useful for evaluating safety and effectiveness of tFUS for sensory feedback in closedloop prosthetic systems.
Applied Sciences, 2022
The central nervous system (CNS) is able to control a very high number of degrees of freedom to p... more The central nervous system (CNS) is able to control a very high number of degrees of freedom to perform complex movements of both upper and lower limbs. However, what strategies the CNS adopts to perform complex tasks are not completely clear and are still being studied. Recent studies confirm that stroke subjects with mild and moderate impairment show altered upper limb muscle patterns, but the muscular patterns of the hand have not completely investigated, although the hand represents a paramount tool for performing activities of daily living (ADLs) and stroke can significantly alter the mobilization of this part of the body. In this context, this study aims at investigating hand muscular synergies in chronic stroke patients and evaluating some possible benefits in the robot-aided rehabilitation treatment of the hand in these subjects. Seven chronic stroke patients with mild-to-moderate impairment (FM>30) were involved in this study. They received a 5-week robot-aided rehabilit...
Frontiers in Neuroscience, 2020
Embodiment is the percept that something not originally belonging to the self becomes part of the... more Embodiment is the percept that something not originally belonging to the self becomes part of the body. Feeling embodiment for a prosthesis may counteract amputees' altered image of the body and increase prosthesis acceptability. Prosthesis embodiment has been studied longitudinally in an amputee receiving feedback through intraneural and perineural multichannel electrodes implanted in her stump. Three factors-invasive (vs non-invasive) stimulation, training, and anthropomorphism-have been tested through two multisensory integration tasks: visuo-tactile integration (VTI) and crossing-hand effect in temporal order judgment (TOJ), the former more sensible to an extension of a safe margin around the body and the latter to action-oriented remapping. Results from the amputee participant were compared with the ones from healthy controls. Testing the participant with intraneural stimulation produced an extension of peripersonal space, a sign of prosthesis embodiment. One-month training extended the peripersonal space selectively on the side wearing the prostheses. More and less-anthropomorphic prostheses benefited of intraneural feedback and extended the peripersonal space. However, the worsening of TOJ performance following arm crossing was present only wearing the more trained, despite less anthropomorphic, prosthesis, suggesting that training was critical for our participant to achieve operative tool-like embodiment.
Science Robotics, 2019
Sensory output produced by a robotic hand during grasping and manipulation evoked real-time nearl... more Sensory output produced by a robotic hand during grasping and manipulation evoked real-time nearly natural force and slippage feedback.
Advances in Mechanical Engineering, 2016
The success of grasping and manipulation tasks of commercial prosthetic hands is mainly related t... more The success of grasping and manipulation tasks of commercial prosthetic hands is mainly related to amputee visual feedback since they are not provided either with tactile sensors or with sophisticated control. As a consequence, slippage and object falls often occur. This article wants to address the specific issue of enhancing grasping and manipulation capabilities of existing prosthetic hands, by changing the control strategy. For this purpose, it proposes a multilevel control based on two distinct levels consisting of (1) a policy search learning algorithm combined with central pattern generators in the higher level and (2) a parallel force/position control managing slippage events in the lower level. The control has been tested on an anthropomorphic robotic hand with prosthetic features (the IH2 hand) equipped with force sensors. Bi-digital and tri-digital grasping tasks with and without slip information have been carried out. The KUKA-LWR has been employed to perturb the grasp s...
Robotics and Autonomous Systems, 2016
• Novel classification of bio-cooperative robotic systems. • A multimodal 3D robotic platform for... more • Novel classification of bio-cooperative robotic systems. • A multimodal 3D robotic platform for upper limb rehabilitation of post stroke patients. • Mechatronic module for guaranteeing arm-weight support during therapy.
Medical & Biological Engineering & Computing, 2015
with InMotion2 robot is used to evaluate its efficacy in discriminating stroke from healthy behav... more with InMotion2 robot is used to evaluate its efficacy in discriminating stroke from healthy behavior. The experimental results have shown that arm angles are reconstructed with a RMSE of 8.3 × 10 -3 rad. Moreover, the comparison between healthy and stroke subjects has revealed different features in the joint space in terms of mean values and standard deviations, which also allow assessing interand intra-subject variability. The findings of this study contribute to the investigation of motor performance in the joint space and Cartesian space of stroke patients undergoing robot-aided therapy, thus allowing: (1) evaluating the outcomes of the therapeutic approach, (2) re-planning the robotic treatment based on patient needs, and (3) understanding pathology-related motor strategies.
2013 IEEE/RSJ International Conference on Intelligent Robots and Systems, 2013
One of the main limitations of systems for Minimally Invasive Robotic Surgery is the lack of hapt... more One of the main limitations of systems for Minimally Invasive Robotic Surgery is the lack of haptic feedback. In this paper, a teleoperated system for robotic surgery is introduced, able to guide the surgeon towards a target anatomy by providing her with force feedback based on Virtual Fixtures (VF). The teleoperated system has a redundant slave robot. A closed-form inverse kinematics is proposed to solve redundancy that is based on an optimization approach in one variable. Four different cost objective functions are proposed in the paper and one is implemented and validated, i.e. the cost function aimed at minimizing the amount of space of the robot in the operative theater during the surgical procedure. The proposed teleoperated architecture has been tested on a teleoperated system composed of a 3-DoFs haptic joystick and a 7-DoFs anthropomorphic manipulator. Experimental tests on 12 volunteer subjects have been carried out. Results demonstrate that a force feedback based on VF provides a statistically significant enhancement of procedure accuracy.
Rehabilitation Robotics, 2007
However, impedance control requires an accurate knowledge of the dynamic parameters of the roboti... more However, impedance control requires an accurate knowledge of the dynamic parameters of the robotic system, in order to compensate the robot dynamics. This increases difficulties in implementing the control law and entails computational burden which may limit the field of application of this powerful technique. Thus, although applicable and adaptable to robot-aided motor therapy, control strategies derived from industrial robotics do not fully satisfy motor therapy requirements and substantial efforts are currently being devoted to robot design and control approaches purposely conceived for improving dependability in human-robot interaction , (Bicchi & Tonietti, 2004), , . Also biomorphic control techniques are being developed for such an application field that are inspired to recent neuroscientific findings on sensorimotor coordination and viscoelastic regulation in humans ). The control system of a machine for robot-aided neuro-rehabilitation is required to be highly adaptable and safe. In particular, the robot control system has to ensure a high level of adaptability to the different motor capabilities of the patients, properly relaxing the requirement of stiffness and precision in the motor task and remarking the maximum priority of safety in the interaction. Also, an ideal control system has to be portable, so to be easily instantiated on different types of rehabilitation machines, i.e., operational rehabilitation machines or else exoskeletal rehabilitation machines, still providing similar therapeutic performance by just readapting few parameters of the control law , . Finally, a good level of flexibility is needed for the machine to be prone to implement different motor tasks, with various kinematic and dynamic characteristics as required by different clinical research protocols. In particular, studies on the typical tasks of rehabilitation motor therapy have shown that, in view of the differences in the patient residual motor capabilities, at least three different operating modalities can be listed which the control has to be able to implement . They are: Passive Mode: the patient is unable to autonomously accomplish the motor task and the robot actively drives her/his limb. The trajectory is fully determined by the robot control system, unless the patients opposes a resistance to motion which exceeds Safety specifications; Active-Assisted Mode: the patients starts the movement but he/ she is unable to reach the target; the robot helps her/his complete the programmed task. When the robot takes control of the task, it goes to passive mode. Initially the machine is fully compliant to human motion, until it stops; Active-Constrained Mode: the patient is able to complete the movement, and the robot can exert a set of programmed force fields to allow a complete recovery of the muscular tone. Here, the trajectory of the end effectors dynamically depends on the interaction between the robot and the human limb. This chapter proposes a control approach which tries to fulfil the requirements of adaptability, safety, portability, and flexibility derived from the application field of rehabilitation robotics and adopts a bio-inspired approach for regulating robot behavior in the interaction with the patient. It originates from the analysis of the basic operating modalities of the rehabilitation motor therapy and, also, from the study of the fundamental mechanisms of biological motor control for generating planar movements and viscoelastic regulation in the human arm (Mussa-Ivaldi et al.
IEEE/ASME Transactions on Mechatronics, 2007
Advanced Robotics, 2008
In recent years, advances and improvements in engineering and robotics have in part been due to s... more In recent years, advances and improvements in engineering and robotics have in part been due to strengthened interactions with the biological sciences. Robots that mimic the complexity and adaptability of biological systems have become a central goal in research and development in robotics. Usually, such a collaboration is addressed to a 2-fold perspective of (i) setting up anthropomorphic platforms as test beds for studies in neuroscience and (ii) promoting new mechatronic and robotic technologies for the development of bio-inspired or humanoid high-performance robotic platforms. This paper provides a brief overview of recent studies on sensorimotor coordination in human motor control and proposes a novel paradigm of adaptive learning for sensorimotor control, based on a multi-network high-level control architecture. The proposed neurobiologically inspired model has been applied to a robotic platform, purposely designed to provide anthropomorphic solutions to neuroscientific requirements. The goal of this work is to use the bioinspired robotic platform as a test bed for validating the proposed model of high-level sensorimotor control, with the aim of demonstrating adaptive and modular control based on acquired competences, with a higher degree of flexibility and generality than conventional robotic controllers, while preserving their robustness. To this purpose, a set of object-dependent, visually guided reach-and-grasp tasks and the associated training phases were first implemented in a multi-network control architecture in simulation. Subsequently, the offline learning realized in simulation was used to produce the input command of reach-and-grasp to the low-level position control of the robotic platform. Experimental trials demonstrated that the adaptive and modular high-level control allowed reaching and grasping of objects located at different positions and objects of variable size, shape and orientation. A future goal would be to address autonomous and progressive learning based on growing competences.
IEEE Access, 2020
The perception of slip is one of the distinctive abilities of human tactile sensing. The sense of... more The perception of slip is one of the distinctive abilities of human tactile sensing. The sense of touch allows recognizing a wide set of properties of a grasped object, such as shape, weight and dimension. Based on such properties, the applied force can be accordingly regulated avoiding slip of the grasped object. Despite the great importance of tactile sensing for humans, mechatronic hands (robotic manipulators, prosthetic hands etc.) are rarely endowed with tactile feedback. The necessity to grasp objects relying on robust slip prevention algorithms is not yet corresponded in existing artificial manipulators, which are relegated to structured environments then. Numerous approaches regarding the problem of slip detection and correction have been developed especially in the last decade, resorting to a number of sensor typologies. However, no impact on the industrial market has been achieved. This paper reviews the sensors and methods so far proposed for slip prevention in artificial tactile perception, starting from more classical techniques until the latest solutions tested on robotic systems. The strengths and weaknesses of each described technique are discussed, also in relation to the sensing technologies employed. The result is a summary exploring the whole state of art and providing a perspective towards the future research directions in the sector.
Abstract-The growing use of Virtual Reality (VR) in rehabilitation is justified by a number of ad... more Abstract-The growing use of Virtual Reality (VR) in rehabilitation is justified by a number of advantages, such as an increase of patient motivation, repetitiveness of learning trials, possibility to tailor treatment to individual subject, safety of the environment, quantitative patient improvement assessment, and remote data access. This paper proposes a novel lowcost evaluation method of patient performance in task-oriented hand rehabilitation grounded on two key elements: a Virtual Environment (VE) which the patient has to interact with, and the Microsoft Kinect motion sensing device, which is used to fully interact with the VE and to feed back patient movements in order to perform an off-line analysis. To this purpose, the VE is equipped with a virtual hand and virtual objects the patient has to interact with. In order to make the interaction between patient and VE possible, a robust marker-based finger tracking algorithm has been developed by using Bayesian estimation methods. ...
Tactile sensing is fundamental for the human hand to achieve high dexterity. Most prosthetic hand... more Tactile sensing is fundamental for the human hand to achieve high dexterity. Most prosthetic hands are still devoid of tactile sensors, implying that the user cannot perceive external stimulation nor react in a fine manner. As a consequence, unforeseen events, e.g., slippage, are difficult to manage. This article proposes an algorithm to perform slippage detection with tactile sensors integrated into prosthetic hands. The algorithm is based on the filtering of the tactile sensor output; rectification and envelope follow the filtering. A binary signal, relating to slippage, is finally computed. An electrical circuit has been designed and built to elaborate the tactile signals. These have been embedded in a bioinspired fingertip mounted on a prosthetic hand, which has been interfaced with a robotic arm to assess the algorithm capability to identify slippage. Eight different surfaces have been employed, while three sliding velocities have been tested with a random interaction force bet...
Sensors
This paper wants to stress the importance of human movement monitoring to prevent musculoskeletal... more This paper wants to stress the importance of human movement monitoring to prevent musculoskeletal disorders by proposing the WGD—Working Gesture Dataset, a publicly available dataset of assembly line working gestures that aims to be used for worker’s kinematic analysis. It contains kinematic data acquired from healthy subjects performing assembly line working activities using an optoelectronic motion capture system. The acquired data were used to extract quantitative indicators to assess how the working tasks were performed and to detect useful information to estimate the exposure to the factors that may contribute to the onset of musculoskeletal disorders. The obtained results demonstrate that the proposed indicators can be exploited to early detect incorrect gestures and postures and, consequently to prevent work-related disorders. The approach is general and independent on the adopted motion analysis system. It wants to provide indications for safely performing working activities...
IEEE Robotics & Automation Magazine
T he COVID-19 pandemic and the related emergency have contributed to the push for innovative solu... more T he COVID-19 pandemic and the related emergency have contributed to the push for innovative solutions applied to health care. In particular, robotics has shown huge potential for contributing to pandemic relief efforts and improving people's quality of life in several scenarios. In this article, a robotic system, characterized by interaction capabilities and autonomous navigation, is developed to be used in a COVID-19 health-care treatment center for logistics and disinfection purposes. The article describes the two-month use of the platform in the University Hospital Campus Bio-Medico (UCBM) COVID-19 treatment center in Rome, Italy, and presents experimental results for the robot's
Sensors
The evolution of technological and surgical techniques has made it possible to obtain an even mor... more The evolution of technological and surgical techniques has made it possible to obtain an even more intuitive control of multiple joints using advanced prosthetic systems. Targeted Muscle Reinnervation (TMR) is considered to be an innovative and relevant surgical technique for improving the prosthetic control for people with different amputation levels of the limb. Indeed, TMR surgery makes it possible to obtain reinnervated areas that act as biological amplifiers of the motor control. On the technological side, a great deal of research has been conducted in order to evaluate various types of myoelectric prosthetic control strategies, whether direct control or pattern recognition-based control. In the literature, different control performance metrics, which have been evaluated on TMR subjects, have been introduced, but no accepted reference standard defines the better strategy for evaluating the prosthetic control. Indeed, the presence of several evaluation tests that are based on di...
Sensors
When combined with assistive robotic devices, such as wearable robotics, brain/neural-computer in... more When combined with assistive robotic devices, such as wearable robotics, brain/neural-computer interfaces (BNCI) have the potential to restore the capabilities of handicapped people to carry out activities of daily living. To improve applicability of such systems, workload and stress should be reduced to a minimal level. Here, we investigated the user’s physiological reactions during the exhaustive use of the interfaces of a hybrid control interface. Eleven BNCI-naive healthy volunteers participated in the experiments. All participants sat in a comfortable chair in front of a desk and wore a whole-arm exoskeleton as well as wearable devices for monitoring physiological, electroencephalographic (EEG) and electrooculographic (EoG) signals. The experimental protocol consisted of three phases: (i) Set-up, calibration and BNCI training; (ii) Familiarization phase; and (iii) Experimental phase during which each subject had to perform EEG and EoG tasks. After completing each task, the NASA...
BioMedical Engineering OnLine
Background: The usability of dexterous hand prostheses is still hampered by the lack of natural a... more Background: The usability of dexterous hand prostheses is still hampered by the lack of natural and effective control strategies. A decoding strategy based on the processing of descending efferent neural signals recorded using peripheral neural interfaces could be a solution to such limitation. Unfortunately, this choice is still restrained by the reduced knowledge of the dynamics of human efferent signals recorded from the nerves and associated to hand movements. Findings: To address this issue, in this work we acquired neural efferent activities from healthy subjects performing hand-related tasks using ultrasound-guided microneurography, a minimally invasive technique, which employs needles, inserted percutaneously, to record from nerve fibers. These signals allowed us to identify neural features correlated with force and velocity of finger movements that were used to decode motor intentions. We developed computational models, which confirmed the potential translatability of these results showing how these neural features hold in absence of feedback and when implantable intrafascicular recording, rather than microneurography, is performed. Conclusions: Our results are a proof of principle that microneurography could be used as a useful tool to assist the development of more effective hand prostheses.
Frontiers in Bioengineering and Biotechnology, Nov 10, 2022
The clinical assessment of the human hand is typically conducted through questionnaires or tests ... more The clinical assessment of the human hand is typically conducted through questionnaires or tests that include objective (e.g., time) and subjective (e.g., grasp quality) outcome measures. However, there are other important indicators that should be considered to quantify grasp and movement quality in addition to the time needed by a subject to execute a task, and this is essential for human and artificial hands that attempt to replicate the human hand properties. The correct estimation of hand kinematics is fundamental for computing these indicators with high fidelity, and a technical background is typically required to perform this analysis. In addition, to understand human motor control strategies as well as to replicate them on artificial devices, postural synergies were widely explored in recent years. Synergies should be analyzed not only to investigate possible modifications due to musculoskeletal and/or neuromuscular disorders, but also to test biomimetic hands. The aim of this work is to present an open source toolbox to perform all-in-one kinematic analysis and clinical assessment of the hand, as well as to perform postural synergies extraction. In the example provided in this work, the tool takes as input the position of 28 retroreflective markers with a diameter of 6 mm, positioned on specific anatomical landmarks of the hand and recorded with an optoelectronic motion capture system, and automatically performs 1) hand kinematic analysis (i.e., computation of 23 joint angles); 2) clinical assessment, by computing indicators that allow quantifying movement efficiency (Peak Grip Aperture), smoothness (Normalized Dimensionless Jerk Grasp Aperture) and speed (Peak Velocity of Grasp Aperture), planning capabilities (Time to Peak Grip Aperture), spatial posture (Wrist and Finger Joint Angles) and grasp stability (Posture of Hand Finger Joints), and 3) postural synergies extraction and analysis through the Pareto, Scree and Loadings plots. Two examples are described to demonstrate the applicability of the toolbox: the first one aiming at performing a clinical assessment of a volunteer and the second one aiming at extracting and analyzing the volunteer's postural synergies. The tool allows calculating joint angles with high accuracy (reconstruction errors below 4 mm and 3.2 mm for the fingers and wrist respectively) and automatically performing clinical assessment and postural synergies extraction. Results can be visually inspected, and data can be saved for any desired post processing analysis. Custom-made protocols to extract joint angles, based on different markersets,
Frontiers in Bioengineering and Biotechnology, Dec 1, 2022
The lack of sensory feedback represents one of the main drawbacks of commercial upper limb prosth... more The lack of sensory feedback represents one of the main drawbacks of commercial upper limb prosthesis. Transcranial Focused Ultrasound Stimulation (tFUS) seems to be a valid non-invasive technique for restoring sensory feedback allowing to deliver acoustic energy to cortical sensory areas with high spatial resolution and depth penetration. This paper aims at studying in simulation the use of tFUS on cortical sensory areas to evaluate its effects in terms of latency ad firing rate of the cells response, for understanding if these parameters influence the safety and the efficacy of the stimulation. In this paper, in order to study the propagation of the ultrasound wave from the transducer to the cortical cells, a multiscale approach was implemented by building a macroscopic model, which estimates the pressure profile in a simplified 2D human head geometry, and coupling it with the SONIC microscale model, that describes the electrical behaviour of a cortical neuron. The influence of the stimulation parameters and of the skull thickness on the latency and the firing rate are evaluated and the obtained behaviour is linked to the sensory response obtained on human subjects. Results have shown that slight changes in the transducer position should not affect the efficacy of the stimulation; however, high skull thickness leads to lower cells activation. These results will be useful for evaluating safety and effectiveness of tFUS for sensory feedback in closedloop prosthetic systems.
Applied Sciences, 2022
The central nervous system (CNS) is able to control a very high number of degrees of freedom to p... more The central nervous system (CNS) is able to control a very high number of degrees of freedom to perform complex movements of both upper and lower limbs. However, what strategies the CNS adopts to perform complex tasks are not completely clear and are still being studied. Recent studies confirm that stroke subjects with mild and moderate impairment show altered upper limb muscle patterns, but the muscular patterns of the hand have not completely investigated, although the hand represents a paramount tool for performing activities of daily living (ADLs) and stroke can significantly alter the mobilization of this part of the body. In this context, this study aims at investigating hand muscular synergies in chronic stroke patients and evaluating some possible benefits in the robot-aided rehabilitation treatment of the hand in these subjects. Seven chronic stroke patients with mild-to-moderate impairment (FM>30) were involved in this study. They received a 5-week robot-aided rehabilit...
Frontiers in Neuroscience, 2020
Embodiment is the percept that something not originally belonging to the self becomes part of the... more Embodiment is the percept that something not originally belonging to the self becomes part of the body. Feeling embodiment for a prosthesis may counteract amputees' altered image of the body and increase prosthesis acceptability. Prosthesis embodiment has been studied longitudinally in an amputee receiving feedback through intraneural and perineural multichannel electrodes implanted in her stump. Three factors-invasive (vs non-invasive) stimulation, training, and anthropomorphism-have been tested through two multisensory integration tasks: visuo-tactile integration (VTI) and crossing-hand effect in temporal order judgment (TOJ), the former more sensible to an extension of a safe margin around the body and the latter to action-oriented remapping. Results from the amputee participant were compared with the ones from healthy controls. Testing the participant with intraneural stimulation produced an extension of peripersonal space, a sign of prosthesis embodiment. One-month training extended the peripersonal space selectively on the side wearing the prostheses. More and less-anthropomorphic prostheses benefited of intraneural feedback and extended the peripersonal space. However, the worsening of TOJ performance following arm crossing was present only wearing the more trained, despite less anthropomorphic, prosthesis, suggesting that training was critical for our participant to achieve operative tool-like embodiment.
Science Robotics, 2019
Sensory output produced by a robotic hand during grasping and manipulation evoked real-time nearl... more Sensory output produced by a robotic hand during grasping and manipulation evoked real-time nearly natural force and slippage feedback.
Advances in Mechanical Engineering, 2016
The success of grasping and manipulation tasks of commercial prosthetic hands is mainly related t... more The success of grasping and manipulation tasks of commercial prosthetic hands is mainly related to amputee visual feedback since they are not provided either with tactile sensors or with sophisticated control. As a consequence, slippage and object falls often occur. This article wants to address the specific issue of enhancing grasping and manipulation capabilities of existing prosthetic hands, by changing the control strategy. For this purpose, it proposes a multilevel control based on two distinct levels consisting of (1) a policy search learning algorithm combined with central pattern generators in the higher level and (2) a parallel force/position control managing slippage events in the lower level. The control has been tested on an anthropomorphic robotic hand with prosthetic features (the IH2 hand) equipped with force sensors. Bi-digital and tri-digital grasping tasks with and without slip information have been carried out. The KUKA-LWR has been employed to perturb the grasp s...
Robotics and Autonomous Systems, 2016
• Novel classification of bio-cooperative robotic systems. • A multimodal 3D robotic platform for... more • Novel classification of bio-cooperative robotic systems. • A multimodal 3D robotic platform for upper limb rehabilitation of post stroke patients. • Mechatronic module for guaranteeing arm-weight support during therapy.
Medical & Biological Engineering & Computing, 2015
with InMotion2 robot is used to evaluate its efficacy in discriminating stroke from healthy behav... more with InMotion2 robot is used to evaluate its efficacy in discriminating stroke from healthy behavior. The experimental results have shown that arm angles are reconstructed with a RMSE of 8.3 × 10 -3 rad. Moreover, the comparison between healthy and stroke subjects has revealed different features in the joint space in terms of mean values and standard deviations, which also allow assessing interand intra-subject variability. The findings of this study contribute to the investigation of motor performance in the joint space and Cartesian space of stroke patients undergoing robot-aided therapy, thus allowing: (1) evaluating the outcomes of the therapeutic approach, (2) re-planning the robotic treatment based on patient needs, and (3) understanding pathology-related motor strategies.
2013 IEEE/RSJ International Conference on Intelligent Robots and Systems, 2013
One of the main limitations of systems for Minimally Invasive Robotic Surgery is the lack of hapt... more One of the main limitations of systems for Minimally Invasive Robotic Surgery is the lack of haptic feedback. In this paper, a teleoperated system for robotic surgery is introduced, able to guide the surgeon towards a target anatomy by providing her with force feedback based on Virtual Fixtures (VF). The teleoperated system has a redundant slave robot. A closed-form inverse kinematics is proposed to solve redundancy that is based on an optimization approach in one variable. Four different cost objective functions are proposed in the paper and one is implemented and validated, i.e. the cost function aimed at minimizing the amount of space of the robot in the operative theater during the surgical procedure. The proposed teleoperated architecture has been tested on a teleoperated system composed of a 3-DoFs haptic joystick and a 7-DoFs anthropomorphic manipulator. Experimental tests on 12 volunteer subjects have been carried out. Results demonstrate that a force feedback based on VF provides a statistically significant enhancement of procedure accuracy.
Rehabilitation Robotics, 2007
However, impedance control requires an accurate knowledge of the dynamic parameters of the roboti... more However, impedance control requires an accurate knowledge of the dynamic parameters of the robotic system, in order to compensate the robot dynamics. This increases difficulties in implementing the control law and entails computational burden which may limit the field of application of this powerful technique. Thus, although applicable and adaptable to robot-aided motor therapy, control strategies derived from industrial robotics do not fully satisfy motor therapy requirements and substantial efforts are currently being devoted to robot design and control approaches purposely conceived for improving dependability in human-robot interaction , (Bicchi & Tonietti, 2004), , . Also biomorphic control techniques are being developed for such an application field that are inspired to recent neuroscientific findings on sensorimotor coordination and viscoelastic regulation in humans ). The control system of a machine for robot-aided neuro-rehabilitation is required to be highly adaptable and safe. In particular, the robot control system has to ensure a high level of adaptability to the different motor capabilities of the patients, properly relaxing the requirement of stiffness and precision in the motor task and remarking the maximum priority of safety in the interaction. Also, an ideal control system has to be portable, so to be easily instantiated on different types of rehabilitation machines, i.e., operational rehabilitation machines or else exoskeletal rehabilitation machines, still providing similar therapeutic performance by just readapting few parameters of the control law , . Finally, a good level of flexibility is needed for the machine to be prone to implement different motor tasks, with various kinematic and dynamic characteristics as required by different clinical research protocols. In particular, studies on the typical tasks of rehabilitation motor therapy have shown that, in view of the differences in the patient residual motor capabilities, at least three different operating modalities can be listed which the control has to be able to implement . They are: Passive Mode: the patient is unable to autonomously accomplish the motor task and the robot actively drives her/his limb. The trajectory is fully determined by the robot control system, unless the patients opposes a resistance to motion which exceeds Safety specifications; Active-Assisted Mode: the patients starts the movement but he/ she is unable to reach the target; the robot helps her/his complete the programmed task. When the robot takes control of the task, it goes to passive mode. Initially the machine is fully compliant to human motion, until it stops; Active-Constrained Mode: the patient is able to complete the movement, and the robot can exert a set of programmed force fields to allow a complete recovery of the muscular tone. Here, the trajectory of the end effectors dynamically depends on the interaction between the robot and the human limb. This chapter proposes a control approach which tries to fulfil the requirements of adaptability, safety, portability, and flexibility derived from the application field of rehabilitation robotics and adopts a bio-inspired approach for regulating robot behavior in the interaction with the patient. It originates from the analysis of the basic operating modalities of the rehabilitation motor therapy and, also, from the study of the fundamental mechanisms of biological motor control for generating planar movements and viscoelastic regulation in the human arm (Mussa-Ivaldi et al.
IEEE/ASME Transactions on Mechatronics, 2007
Advanced Robotics, 2008
In recent years, advances and improvements in engineering and robotics have in part been due to s... more In recent years, advances and improvements in engineering and robotics have in part been due to strengthened interactions with the biological sciences. Robots that mimic the complexity and adaptability of biological systems have become a central goal in research and development in robotics. Usually, such a collaboration is addressed to a 2-fold perspective of (i) setting up anthropomorphic platforms as test beds for studies in neuroscience and (ii) promoting new mechatronic and robotic technologies for the development of bio-inspired or humanoid high-performance robotic platforms. This paper provides a brief overview of recent studies on sensorimotor coordination in human motor control and proposes a novel paradigm of adaptive learning for sensorimotor control, based on a multi-network high-level control architecture. The proposed neurobiologically inspired model has been applied to a robotic platform, purposely designed to provide anthropomorphic solutions to neuroscientific requirements. The goal of this work is to use the bioinspired robotic platform as a test bed for validating the proposed model of high-level sensorimotor control, with the aim of demonstrating adaptive and modular control based on acquired competences, with a higher degree of flexibility and generality than conventional robotic controllers, while preserving their robustness. To this purpose, a set of object-dependent, visually guided reach-and-grasp tasks and the associated training phases were first implemented in a multi-network control architecture in simulation. Subsequently, the offline learning realized in simulation was used to produce the input command of reach-and-grasp to the low-level position control of the robotic platform. Experimental trials demonstrated that the adaptive and modular high-level control allowed reaching and grasping of objects located at different positions and objects of variable size, shape and orientation. A future goal would be to address autonomous and progressive learning based on growing competences.
IEEE Access, 2020
The perception of slip is one of the distinctive abilities of human tactile sensing. The sense of... more The perception of slip is one of the distinctive abilities of human tactile sensing. The sense of touch allows recognizing a wide set of properties of a grasped object, such as shape, weight and dimension. Based on such properties, the applied force can be accordingly regulated avoiding slip of the grasped object. Despite the great importance of tactile sensing for humans, mechatronic hands (robotic manipulators, prosthetic hands etc.) are rarely endowed with tactile feedback. The necessity to grasp objects relying on robust slip prevention algorithms is not yet corresponded in existing artificial manipulators, which are relegated to structured environments then. Numerous approaches regarding the problem of slip detection and correction have been developed especially in the last decade, resorting to a number of sensor typologies. However, no impact on the industrial market has been achieved. This paper reviews the sensors and methods so far proposed for slip prevention in artificial tactile perception, starting from more classical techniques until the latest solutions tested on robotic systems. The strengths and weaknesses of each described technique are discussed, also in relation to the sensing technologies employed. The result is a summary exploring the whole state of art and providing a perspective towards the future research directions in the sector.
Abstract-The growing use of Virtual Reality (VR) in rehabilitation is justified by a number of ad... more Abstract-The growing use of Virtual Reality (VR) in rehabilitation is justified by a number of advantages, such as an increase of patient motivation, repetitiveness of learning trials, possibility to tailor treatment to individual subject, safety of the environment, quantitative patient improvement assessment, and remote data access. This paper proposes a novel lowcost evaluation method of patient performance in task-oriented hand rehabilitation grounded on two key elements: a Virtual Environment (VE) which the patient has to interact with, and the Microsoft Kinect motion sensing device, which is used to fully interact with the VE and to feed back patient movements in order to perform an off-line analysis. To this purpose, the VE is equipped with a virtual hand and virtual objects the patient has to interact with. In order to make the interaction between patient and VE possible, a robust marker-based finger tracking algorithm has been developed by using Bayesian estimation methods. ...
Tactile sensing is fundamental for the human hand to achieve high dexterity. Most prosthetic hand... more Tactile sensing is fundamental for the human hand to achieve high dexterity. Most prosthetic hands are still devoid of tactile sensors, implying that the user cannot perceive external stimulation nor react in a fine manner. As a consequence, unforeseen events, e.g., slippage, are difficult to manage. This article proposes an algorithm to perform slippage detection with tactile sensors integrated into prosthetic hands. The algorithm is based on the filtering of the tactile sensor output; rectification and envelope follow the filtering. A binary signal, relating to slippage, is finally computed. An electrical circuit has been designed and built to elaborate the tactile signals. These have been embedded in a bioinspired fingertip mounted on a prosthetic hand, which has been interfaced with a robotic arm to assess the algorithm capability to identify slippage. Eight different surfaces have been employed, while three sliding velocities have been tested with a random interaction force bet...
Sensors
This paper wants to stress the importance of human movement monitoring to prevent musculoskeletal... more This paper wants to stress the importance of human movement monitoring to prevent musculoskeletal disorders by proposing the WGD—Working Gesture Dataset, a publicly available dataset of assembly line working gestures that aims to be used for worker’s kinematic analysis. It contains kinematic data acquired from healthy subjects performing assembly line working activities using an optoelectronic motion capture system. The acquired data were used to extract quantitative indicators to assess how the working tasks were performed and to detect useful information to estimate the exposure to the factors that may contribute to the onset of musculoskeletal disorders. The obtained results demonstrate that the proposed indicators can be exploited to early detect incorrect gestures and postures and, consequently to prevent work-related disorders. The approach is general and independent on the adopted motion analysis system. It wants to provide indications for safely performing working activities...
IEEE Robotics & Automation Magazine
T he COVID-19 pandemic and the related emergency have contributed to the push for innovative solu... more T he COVID-19 pandemic and the related emergency have contributed to the push for innovative solutions applied to health care. In particular, robotics has shown huge potential for contributing to pandemic relief efforts and improving people's quality of life in several scenarios. In this article, a robotic system, characterized by interaction capabilities and autonomous navigation, is developed to be used in a COVID-19 health-care treatment center for logistics and disinfection purposes. The article describes the two-month use of the platform in the University Hospital Campus Bio-Medico (UCBM) COVID-19 treatment center in Rome, Italy, and presents experimental results for the robot's
Sensors
The evolution of technological and surgical techniques has made it possible to obtain an even mor... more The evolution of technological and surgical techniques has made it possible to obtain an even more intuitive control of multiple joints using advanced prosthetic systems. Targeted Muscle Reinnervation (TMR) is considered to be an innovative and relevant surgical technique for improving the prosthetic control for people with different amputation levels of the limb. Indeed, TMR surgery makes it possible to obtain reinnervated areas that act as biological amplifiers of the motor control. On the technological side, a great deal of research has been conducted in order to evaluate various types of myoelectric prosthetic control strategies, whether direct control or pattern recognition-based control. In the literature, different control performance metrics, which have been evaluated on TMR subjects, have been introduced, but no accepted reference standard defines the better strategy for evaluating the prosthetic control. Indeed, the presence of several evaluation tests that are based on di...
Sensors
When combined with assistive robotic devices, such as wearable robotics, brain/neural-computer in... more When combined with assistive robotic devices, such as wearable robotics, brain/neural-computer interfaces (BNCI) have the potential to restore the capabilities of handicapped people to carry out activities of daily living. To improve applicability of such systems, workload and stress should be reduced to a minimal level. Here, we investigated the user’s physiological reactions during the exhaustive use of the interfaces of a hybrid control interface. Eleven BNCI-naive healthy volunteers participated in the experiments. All participants sat in a comfortable chair in front of a desk and wore a whole-arm exoskeleton as well as wearable devices for monitoring physiological, electroencephalographic (EEG) and electrooculographic (EoG) signals. The experimental protocol consisted of three phases: (i) Set-up, calibration and BNCI training; (ii) Familiarization phase; and (iii) Experimental phase during which each subject had to perform EEG and EoG tasks. After completing each task, the NASA...
BioMedical Engineering OnLine
Background: The usability of dexterous hand prostheses is still hampered by the lack of natural a... more Background: The usability of dexterous hand prostheses is still hampered by the lack of natural and effective control strategies. A decoding strategy based on the processing of descending efferent neural signals recorded using peripheral neural interfaces could be a solution to such limitation. Unfortunately, this choice is still restrained by the reduced knowledge of the dynamics of human efferent signals recorded from the nerves and associated to hand movements. Findings: To address this issue, in this work we acquired neural efferent activities from healthy subjects performing hand-related tasks using ultrasound-guided microneurography, a minimally invasive technique, which employs needles, inserted percutaneously, to record from nerve fibers. These signals allowed us to identify neural features correlated with force and velocity of finger movements that were used to decode motor intentions. We developed computational models, which confirmed the potential translatability of these results showing how these neural features hold in absence of feedback and when implantable intrafascicular recording, rather than microneurography, is performed. Conclusions: Our results are a proof of principle that microneurography could be used as a useful tool to assist the development of more effective hand prostheses.