腦中風為腦部血管局部性的阻塞或出血造成病人死亡或言語、行動、身體機能與日常功能障礙，為全球與台灣常見且重要的疾病。中風病患常需長期接受復健訓練、重新學習使用患側上、下肢進行功能性動作，然而中風後上肢的功能性回復遠低於下肢，嚴重影響日常生活功能執行。由於大腦具可塑性，使中風患者仍具感覺動作功能恢復的潛能，積極配合適當的動作治療可增強動作學習效果。臨床上治療師以一對一方式執行中風後評估與訓練，屬於勞力集中方式且缺乏客觀量化評估動作控制表現。本研究目的為整合臨床復健醫學、生物力學、動作控制與動作學習之理論基礎，配合機電整合科技以設計發展機器手臂輔助復健訓練系統以提供中風病人單側上肢動作特性量化評估與復健訓練，特定目標包括：(1)利用上肢末端點運動學及動力學變化分析探討正常受試者與中風患者被動或主動動作特性、(2)利用外加干擾以估算上肢末端點生物力學特性、(3)設計機器手臂輔助訓練計畫並評估其適用性與訓練效果。
本研究第一階段為設計發展機器手臂輔助復健系統，其設計考量包含：提供使用者不同路徑之單側上肢平面動作，提供復健人員方便監控、資料擷取之GUI操作介面，並以螢幕顯示器提供使用者動作表現相關視覺資訊迴授。系統功能性設計含括主動模式、被動模式與評估模式。本機器手臂系統採用平行五連機構提供二維動作、兩組伺服馬達驅動平行五連桿、兩組電磁離合器配合扭力計與迴授電路控制扭矩輸出大小、力感測器擷取上肢末端點作用力、編碼器量測各連桿轉動角度、含肘支撐架之工作平台、螢幕顯示器、工業電腦、人機操作介面。運動學/動力學方程式與系統控制架構以Borland C++ Builder軟體進行並透過訊號傳輸介面控制訊號以完成所需之功能執行。系統校正包括力感測器、伺服馬達及電磁離合器配合扭力計與迴授電路控制、連桿末端點執行軌跡及軌跡速度。
第二階段研究為臨床應用研究，包含以機器手臂輔助系統量化評估上肢主動、被動動作特徵與上肢末端點生物力學特性於正常人與中風患者間之差異，同時設計系統化之機器手臂輔助訓練計畫並評估其訓練效果。本研究共有十位正常受試者（控制組）與十位中風受試者（實驗組），中風患者臨床評估包含上肢肌肉張力(MAS)、布朗司壯級分(Brunnstrom Stage)及Fugl-Meyer上肢動作功能評估量表。兩組受試者分別以機器手臂系統進行上肢主動、被動動作與上肢末端點生物力學特性評估，其中實驗組內之三位受試者接受至少三個月之系統化之機器手臂輔助訓練並評估其訓練效果。本研究評估所得參數為臨床分級與評估量表得分與機器手臂輔助評估所計算之量化參數，包含於被動動作時為上肢系統張力特性(Force profile)，於主動動作時為運動學特性(含軌跡、速度、加速度與Jerk cost)，於評估模式時為末端點彈性與黏性矩陣及其特徵值與特徵向量；所得參數以Kruskal-Wallis Test 及 Mann-Whitney U Test 進行統計分析，並使用回歸分析於臨床參數與機器手臂輔助評估參數間之相關性。
系統校正結果顯示本研究之機器手臂輔助復健訓練系統具有高度穩定性。於被動動作時，中風患者上肢異常肌肉張力與力學特性反映於末端點張力特性上；於主動動作時，中風患者上肢異常協同動作模式與痙攣亦反映於末端點運動學特性上，包含明顯分段之速度曲線與明顯增加之Jerk cost；於上肢末端點生物力學特徵評估上，結果也顯示中風患者末端點剛性與黏性皆明顯大於正常受試者，其異常之神經肌肉控制機制及已改變的生物力學特性可藉由上肢系統末端點之運動學/動力學加以評估量化。於機器手臂輔助動作訓練結果也顯示，使用本系統給予系統化之復健訓練計畫對增進中風病患上肢功能上具有正面的效益，並反映於臨床功能量表上。因此，機器手臂輔助復健訓練系統可提供客觀量化之上肢動作特性與上肢末端點生物力學特徵參數以輔助臨床評估，並提供可系統程式化且有效之上肢動作訓練模式於臨床復健上。未來期望將機器手臂輔助評估與復健訓練，擴充到空間軌跡動作以更接近日常功能性動作模式，並將其推廣應用於臨床上，藉由更多臨床研究進一步探討神經肌肉病變患者上肢不同動作特徵與生物力學特性等，提供更科學化、系統化之研究方法與成果貢獻於臨床復健醫學、基礎科學與生物力學等領域。

Stroke, a sudden/focal neurological deficit from ischemic or hemorrhagic lesions in the brain, is the leading cause of long-term disabilities. Functional recovery of upper limb is usually limited and deteriorates activities of daily living. In clinics, post-stroke rehabilitation is labor-intensive and limited to subjective assessment. The advent of mechatronic technology, movement sciences, biomechanics, motor control and motor learning theories provides new medical technologies and becomes potentially useful in the clinical rehabilitation. The purpose of this research is to design and develop a robot-aided rehabilitation system for quantitative evaluation and movement training for the hemiplegic upper limb. The research is aimed to (1) design/develop robot-aided system for objective evaluation and novel therapeutic process; (2) investigate active/passive movement characteristics through kinematic and kinetic measures for the able-bodied and the post-stroke; (3) characterize upper-limb endpoint biomechanics through measuring changes in endpoint force in response to perturbations; (4) develop robot-aided therapeutic programs for clinical applications and evaluate the efficacy of robot-aided training on upper-limb motor performance.
This research is divided into two stages of experiments. Phase I is focused on design and development of a robot-aided rehabilitation system. The conceptual design for the robot-aided training system is to include functions: 1) providing various active/passive planer movements for the end-effector to exercise upper limb; 2) providing various force field for training practice; 3) recording endpoint kinematics and kinetics; 4) providing assessment of endpoint biomechanics and 5) providing visual feedback during task executions. The system consists of a five-bar linkage manipulator for planer movement, a six-axes force sensor for forces recording, two servo motors to drive the manipulator, two sets of clutches with torque sensors and integrated circuit to control torque output, encoders to monitor the angles of eacj linkage. The GUI controlling panel, kinematic/kinetic equations, signal transmission and data acquisition are programmed by Borland C++ Builder. The force sensor, servo motors, clutches, and trajectory and trajectory velocity are calibrated.
Phase II consists of robot-aided assessment and movement therapy. Robot-aided assessment is applied to characterize active/passive upper-limb movement through changes of endpoint kinematics/kinetics and for investigate endpoint biomechanical properties through perturbations for able-bodied and stroke subjects. Robot-aided movement therapy includes develop therapeutic programs and evaluate the efficacy of robot-aided training. Ten able-bodied subjects and ten post-stroke subjects were recruited in this study. Assessment of muscle tone, Brunnstrin stage and Fugl-Meyer motor scale are conducted for each stroke subject. Three stroke subjects were recruited in the robot-aided training programs. The movement parameters of robot-aided assessment primarily includes: the force profiles from passive movement, the kinematic measures (coordinates, velocity, acceleration and jerk) from active movement and the endpoint stiffness/viscosity matrix which can be characterized by eigenvalues and eigenvectors. Kruskal-Wallis test and Mann-Whitney U test were used for statistical analysis. The efficacy of robot-aided therapeutic protocols on motor performance is also investigated through clinical and the robot-aided assessment.
The results of system calibration show that the robot-aided system is functional well. During passive movement, the post-stroke revealed abnormal force profiles for each trajectory. During active movement, the stroke subjects also produced larger kinematic error and less smooth movement, especially for the jerk cost and segmented velocity profile. During estimating endpoint biomechanics, significant increases in endpoint stiffness and endpoint viscosity are revealed by the stroke subjects. The results of these biomechanical characteristics of the post-stroke demonstrated impaired motor control and changed viscoelastic properties of upper-limb movement. Besides, positive training effects of robot-aided movement training were revealed by this research. The robot-aided assessment during active movement provided quantitative measures which are positively related to the movement recovery status and to the clinical scale. The robot-aided system can facilitate further investigations for improved understanding of fundamental biomechanics and movement science in the motor control of upper limb. It also can assist in the evaluation of new therapeutic modalities, and characterize the recovery process for clinical applications.

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