Design, implementation, control, and user evaluations of assiston-arm self-aligning upper-extremity exoskeleton

Physical rehabilitation therapy is indispensable for treating neurological disabilities. The use of robotic devices for rehabilitation holds high promise, since these devices can bear the physical burden of rehabilitation exercises during intense therapy sessions, while therapists are employed as decision makers. Robot-assisted rehabilitation devices are advantageous as they can be applied to patients with all levels of impairment, allow for easy tuning of the duration and intensity of therapies and enable customized, interactive treatment protocols. Moreover, since robotic devices are particularly good at repetitive tasks, rehabilitation robots can decrease the physical burden on therapists and enable a single therapist to supervise multiple patients simultaneously; hence, help to lower cost of therapies. While the intensity and quality of manually delivered therapies depend on the skill and fatigue level of therapists, high-intensity robotic therapies can always be delivered with high accuracy. Thanks to their integrated sensors, robotic devices can gather measurements throughout therapies, enable quantitative tracking of patient progress and development of evidence-based personalized rehabilitation programs. In this dissertation, we present the design, control, characterization and user evaluations of AssistOn-Arm, a powered, self-aligning exoskeleton for robotassisted upper-extremity rehabilitation. AssistOn-Arm is designed as a passive back-driveable impedance-type robot such that patients/therapists can move the device transparently, without much interference of the device dynamics on natural movements. Thanks to its novel kinematics and mechanically transparent design, AssistOn-Arm can passively self-align its joint axes to provide an ideal match between human joint axes and the exoskeleton axes, guaranteeing ergonomic movements and comfort throughout physical therapies. The self-aligning property of AssistOn-Arm not only increases the usable range of motion for robot-assisted upper-extremity exercises to cover almost the whole human arm workspace, but also enables the delivery of glenohumeral mobilization (scapular elevation/depression and protraction/retraction) and scapular stabilization exercises, extending the type of therapies that can be administered using upper-extremity exoskeletons. Furthermore, the self-alignment property of AssistOn-Arm signi cantly shortens the setup time required to attach a patient to the exoskeleton. As an impedance-type device with high passive back-driveability, AssistOn- Arm can be force controlled without the need of force sensors; hence, high delity interaction control performance can be achieved with open-loop impedance control. This control architecture not only simpli es implementation, but also enhances safety (coupled stability robustness), since open-loop force control does not su er from the fundamental bandwidth and stability limitations of force-feedback. Experimental characterizations and user studies with healthy volunteers con- rm the transparency, range of motion, and control performance of AssistOn- Ar

Système mécatronique d'aide à l'alimentation pour les personnes vivant avec des troubles de mouvement aux membres supérieurs

Plusieurs personnes vivent avec des incapacités qui affectent le contrôle du mouvement des membres supérieurs. Ces troubles de mouvement peuvent être présents sous forme de contractions involontaires, de mouvements spasmodiques ou de tremblements. Ceux-ci limitent ces personnes dans la réalisation de plusieurs tâches de la vie quotidienne. Des aides techniques peuvent alors servir à faciliter les déplacements, à compenser un manque de tonus musculaire ou à permettre la manipulation d'objets. Plus particulièrement, des aides techniques sont conçues pour les personnes vivant avec des troubles de mouvement aux membres supérieurs pour leur permettre de s'alimenter de manière autonome. Par contre, plusieurs facteurs limitent l'utilisation des aides techniques actuelles, tels que leur prix élevé ou leur complexité d'utilisation. L'objectif de ce mémoire est le développement d'une nouvelle aide à l'alimentation pour les personnes vivant avec des incoordinations motrices au niveau des membres supérieurs. L'hypothèse est que l'utilisation de l'aide à l'alimentation développée permettra d'améliorer la capacité des personnes avec des troubles de mouvement à s'alimenter de manière autonome. Cette assistance augmenterait l'implication de l'utilisateur lors des repas tout en réduisant la charge de travail des aidants ou préposés. Deux systèmes ont été développés : une version passive et une version active. La version passive consiste en un assemblage de barres qui maintiennent l'orientation de l'ustensile constante et amorti mécaniquement les mouvements brusques involontaires. Une version active a ensuite été développée, où des actionneurs remplacent les amortisseurs mécaniques, afn d'offrir une assistance plus intelligente.Many people are living with neurological disorders such as cerebral palsy, stroke, muscular dystrophy or dystonia, that affect the control of upper limb movement. These motor disorders can be involuntary contractions, spasmodic movement or tremors. These disorders limit in the accomplishment of several tasks of daily life. Technical aids can then be used to facilitate movement, to compensate for a lack of muscle tone or to allow the manipulation of objects. In particular, assistive devices are designed for people with upper limb movement disorders to eat autonomously. Several factors limit the use of current assistive devices, such as their high price or high complexity. The aim of this thesis is the development of a new eating aid for people with upper limbs motor disorders. The hypothesis is that the use of the eating assistance developed will improve the ability of people with movement disorders to eat autonomously. This assistance would increase user involvement while reducing the workload of the caregiver. Two assistive prototypes have been developed : a passive version and an active version. The passive version consists of a bar assembly that maintains the constant orientation of the utensil and mechanically dampens involuntary movements. An active version was then developed, where actuators replace the mechanical dampers, in order to offer a more intellignent assistance

A Gravity Compensation-Based Upper Limb Rehabilitation Robot

本論文呈現一個用人體手臂動態模型去模擬受試者意志活動的控制器。為了去達成這個目的，首先我們必須先分析從力量/扭力感測器所量測到的資訊進而得到真正受試者各關節所施的扭力。由得到的真正受試者施的扭力乘上一個增益，這個控制器可以去實現一些物理治療的訓練，包括主動模式、輔助模式以及阻抗模式在我們自製的上肢復健機器手臂。另外，藉由改變手臂動態模型的重力項的比例，這個控制器更可以達到不同程度的上肢手臂重力補償。最後，透過幾個實際的實驗來驗證此控制器的效能及成果。This thesis presents a control scheme using human arm dynamics to simulate the subject''s volitional movement. To achieve this goal, first, it has to obtain the torques purely generated from the subject from force/torque sensors. With this result, the controller can implement the therapeutic exercises, consisting of the active range of motion (AROM), the active-assistive range of motion (A-AROM), and the resistive range of motion (RROM) modes on our self-built upper limb rehabilitation robot arm by feeding back the torques purely generated from the subject with different gains to the associated arm controller. Besides, by modifying the gravity term in human arm dynamics, this controller can achieve different levels of gravity compensation of the upper limb. To validate our design, some realistic experiments are conducted and the performance of our design is demonstrated