90 research outputs found

    Design and acceptability assessment of a new reversible orthosis

    Get PDF
    International audience— We present a new device aimed at being used for upper limb rehabilitation. Our main focus was to design a robot capable of working in both the passive mode (i.e. the robot shall be strong enough to generate human-like movements while guiding the weak arm of a patient) and the active mode (i.e. the robot shall be able of following the arm without disturbing human natural motion). This greatly challenges the design, since the system shall be reversible and lightweight while providing human compatible strength, workspace and speed. The solution takes the form of an orthotic structure, which allows control of human arm redundancy contrarily to clinically available upper limb rehabilitation robots. It is equipped with an innovative transmission technology, which provides both high gear ratio and fine reversibility. In order to evaluate the device and its therapeutic efficacy, we compared several series of pointing movements in healthy subjects wearing and not wearing the orthotic device. In this way, we could assess any disturbing effect on normal movements. Results show that the main movement characteristics (direction, duration, bell shape profile) are preserved

    Design and acceptability assessment of a new reversible orthosis

    Get PDF
    We present a new device aimed at being used for upper limb rehabilitation. Our main focus was to design a robot capable of working in both the passive mode (i.e. the robot shall be strong enough to generate human-like movements while guiding the weak arm of a patient) and the active mode (i.e. the robot shall be able of following the arm without disturbing human natural motion). This greatly challenges the design, since the system shall be reversible and lightweight while providing human compatible strength, workspace and speed. The solution takes the form of an orthotic structure, which allows control of human arm redundancy contrarily to clinically available upper limb rehabilitation robots. It is equipped with an innovative transmission technology, which provides both high gear ratio and fine reversibility. In order to evaluate the device and its therapeutic efficacy, we compared several series of pointing movements in healthy subjects wearing and not wearing the orthotic device . In this way, we could assess any disturbing effect on normal movements. Results show that the main movement characteristics (direction, duration, bell shape profile) are preserved. ©2008 IEEE

    Design of an innovative exoskeletal forearm-wrist mechanism

    Get PDF
    International audienceThis paper presents an innovative 3-joints structure designed as the forearm-wrist of a force controlled exoskeleton. It is composed of an open parallel mechanism both fitting the human forearm and able to rotate on its longitudinal joint (prono-supination), in a similar manner of the ulna-radius movement. This structure advantageously replaces circular guidings in terms of mass, volume and friction and can be freely scaled. A lightweight 3 dof forearm-wrist mechanism is proposed as an integral rotation module for the general-purpose arm exoskeleton ABLE 7 D

    A methodology to design kinematics of fixations between an orthosis and a human member

    Get PDF
    International audienceThe design of robotic orthoses focuses strongly on replicating kinematics of human limb. However, often sophisticated mechanisms which attempt at reproducing complex kinematics of human joints fails in adapting to geometrical variations of subjects sizes and eccentricities. One major that arrises from this mismatching is an occurrence of hyperstaticity induced by the uncontrolled interaction forces. In this paper, we take the point of view of statics to investigate the force transmission problem, which is required for a fine force control. The main result of this study focuses on designing fixations between the orthosis and the human limb that provide additional degrees of freedom. The method involves two steps. Firstly, a set of possible solutions with respect to the isostaticity criterion is derived. Then, among these possible solutions, a set of design rules considering physiological aspects of transmitting forces to human limbs is used to select a preferred configuration. As an example, the method is applied to an existing 4 active DOF arm orthosis

    Real-time Hybrid Locomotion Mode Recognition for Lower-limb Wearable Robots

    Get PDF
    Real-time recognition of locomotion-related activities is a fundamental skill that the controller of lower-limb wearable robots should possess. Subject-specific training and reliance on electromyographic interfaces are the main limitations of existing approaches. This study presents a novel methodology for real-time locomotion mode recognition of locomotion-related activities in lower-limb wearable robotics. A hybrid classifier can distinguish among seven locomotion-related activities. First, a time-based approach classifies between static and dynamical states based on gait kinematics data. Second, an event-based fuzzy logic method triggered by foot pressure sensors operates in a subject-independent fashion on a minimal set of relevant biomechanical features to classify among dynamical modes. The locomotion mode recognition algorithm is implemented on the controller of a portable powered orthosis for hip assistance. An experimental protocol is designed to evaluate the controller performance in an out-of-lab scenario without the need for a subject-specific training. Experiments are conducted on six healthy volunteers performing locomotion-related activities at slow, normal, and fast speeds under the zero-torque and assistive mode of the orthosis. The overall accuracy rate of the controller is 99.4% over more than 10,000 steps, including seamless transitions between different modes. The experimental results show a successful subject-independent performance of the controller for wearable robots assisting locomotion-related activities

    Design Of An Anthropomorphic Upper Limb Exoskeleton Actuated By Ball-Screws And Cables

    Get PDF
    International audienceThis paper presents the design of ABLE, an anthropomorphic upper limb exoskeleton integrally actuated by highly reversible ball-screw and cable (SCS standing for Screw-and-Cable-System) allowing true joint torque control without force sensor. Their unique kinematics allows their integration in the structure thanks to dedicated mechanical innovations such as the shoulder articulation and the forearm-wrist. The result is an anthropomorphic, lightweight, open architecture which avoids imprisoning the human limb. Applicative projects are briefly presented in: medical rehabilitation, teleoperation and haptics (VR).Lucrarea prezintă proiectul lui ABLE, un exoschelet al braţului, integralacţionat de un sistem şurub cu cap sferic şi cablu (SSC, de la sistem cu şurub şicablu), puternic reversibil, care permite controlul real al momentului în articulaţiefără senzor de forţă. Cinematica unică permite integrarea lui în structură graţieinovaţiilor mecanice speciale, precum articulaţia umărului şi încheieturaantebraţului. Rezultatul este o arhitectură deschisă, uşoară, antropomorfică, careevită încorsetarea braţului uman. Sunt prezentate pe scurt proiecte de aplicaţii în:recuperarea medicală, telechirurgie şi interfaţare haptică (RV)

    Dynamic Elastomeric Fabric Orthoses (DEFO) and physiotherapy after Botulinum toxin (BT) in adults with focal spasticity: A feasibility study using mixed methods.

    Get PDF
    Acknowledgements: DM Orthotics Ltd©Title: Dynamic Elastomeric Fabric Orthoses (DEFO) And Physiotherapy After Botulinum toxin (BT) In Adults With Spasticity: A Feasibility Study Using Mixed Methods. Aim: A study to investigate the potential feasibility (including estimated effect-size), acceptability and health benefits of DEFO and physiotherapy in treatment of spasticity following intramuscular injection of BT. Participants: Adults living in the community with focal spasticity of the upper or lower limb (Modified Ashworth Scale 2-3) recruited at a regional Spasticity Clinic. Intervention: provision of an individually fitted DEFO (worn daily up to 8 hours) usual care and physiotherapy (as required) for 6 weeks. Methods: Mixed methods embedded design feasibility study: Quantitative: Feasibility single-blind RCT: Intervention Group: DEFO intervention protocol, usual care and physiotherapy, Control Group: usual care and physiotherapy. Qualitative: Topic guided interviews of the intervention group and clinicians. Measures: Goal Attainment Scale (GAS) primary measure and secondary measures for function and care benefit; Arm Activity measure (ArmA), Leeds Arm Impact Score (LASIS), VAS for pain, European Quality of Life-5 Dimensions (EQ-5D), gait velocity (10MTT). Variance and fidelity was captured with: DEFO wearing record, Activity Log, clinical records and Physiotherapy modalities. Analysis: ANCOVA adjusted means and statistical comparison for significance of measures (at baseline, after six weeks and twelve weeks) between groups and to inform power calculations. Thematic Analysis of clinician and participant transcribed interviews. Quantitative and qualitative findings were integrated and triangulated to inform a larger study. Results: Participants (n=25) recruited over twelve months, (n=22) completed study. Statistical analysis showed improvements in both groups with greater health benefit in the intervention group with mean difference in the GAS of 12.17 (95%CI: 3.16 to 21.18; p = 0.014) but no statistical significance in the secondary measures. Effect-size was estimated from the GAS findings for 200 per group for a larger study. Physiotherapy modalities for spasticity were linked to ‘passive’ and ‘active’ function. Feasibility and acceptability was established with Thematic Analysis providing valuable insight into patient and clinician perspectives on disability. Conclusions: Findings indicated potential added health benefits including carer benefit. Feasibility, acceptability and clinical application of DEFO as a potential new intervention were established. This has implications for future spasticity management with patient benefit for passive and active function. Further research is indicated with a fully powered study (based on the GAS sample results) to evaluate DEFO efficacy in people with spasticity following BT. Key words: Spasticity, Botulinum toxin, physiotherapy, dynamic orthoses.Registered with local NHS R&D and Exeter University

    Integrated Methodologies and Technologies for the Design of Advanced Biomedical Devices

    Get PDF
    Biomedical devices with tailored properties were designed using advanced methodologies and technologies. In particular, design for additive manufacturing, reverse engineering, material selection, experimental and theoretical analyses were properly integrated. The focus was on the design of: i) 3D additively manufactured hybrid structures for cranioplasty; ii) technical solutions and customized prosthetic devices with tailored properties for skull base reconstruction after endoscopic endonasal surgery; iii) solid-lattice hybrid structures with optimized properties for biomedical applications. The feasibility of the proposed technical solutions was also assessed through virtual and physical models
    corecore