本論文目標在於發展主動式之雙輪差速同動控制及被動式之電動輔助控制兩項技術，應用於下肢殘疾者代步用之雙馬達電動輪椅(Power Chair)，使之具有省力操作、易折疊收納、及不受環境限制等優點，使電動代步輔具更易於操控在環境阻抗變化大或狹窄、彎曲之空間，進而使下肢殘疾者之代步功能更具彈性。
　　在差速同動控制技術問題上，本研究定義出差速同動之數學模型，透過PI補償器設計，推導出差速耦合所需之阻尼與彈性力，用以降低兩輪之同動誤差，並解決輪椅行進推力及行進路徑同時控制之技術瓶頸。而在電動輔助控制技術研究部分，則提出估測器頻域比較方法，設計出適當的狀態估測器，配合加速度與外擾回授控制，取代傳統之力量感測裝置，並透過模擬與實驗，進一步實現電動輔助之效果。

　The objective of this thesis is to develop the active differential control and the power-assisted control techniques which are applied to the double-motor power chair for disabled people. Under the proposed control architecture, the power chair possesses several advantages such as effort-saving, easy to put away and unrestricted to the environment. Hence, the power chair can be easily operated in the severe and varied conditions or the narrow and winding space, and the function of assistive mobility can be improved.
　On the differential control strategy issue, the mathematical model is derived in this thesis. Through the design of a PI compensator, the required damping and elastic force of the differential coupling can be obtained to decrease the synchronized error between the two wheels and to solve the technical problem of simultaneously controlling the thrust force and the moving path. For the power-assisted control technique, the observer comparison method in frequency domain is proposed. Conventional force sensors can be replaced by designing the proper state observer with the acceleration and disturbance feedback control. Simulation and experiments are both conducted to realize the power assisted techniques.

[1]　Catalogue e.motion, e.motion, Ulrich Alber GmbH Co., Germany.
[2]　R. A. Cooper, “Push for Power,” The interdisciplinary Journal of Rehabilitation, March 2004, http://www.rehabpub.com/features/32004/.
[3]　S. Komada, M. Ishida, K. Ohnishi, and T. Hori, “Motion Control of Linear Synchronous Motors Based on Disturbance Observer,” IEEE IECON, vol.1, pp.154-159, 1990.
[4]　G. Ellis, Control System Design Guide, Academic Press, San Diego, 2001.
[5]　Uchiyama, Atsushi, Ogata and Hiroaki, “Power-Assisted Wheelchair,” U. S. Patent 6,354,390, March 23, 1998.
[6]　R. A. Cooper, T. A. Corfman, S. G. Fitzgerald, M. L. Boninger, D. M. Spaeth, W. Ammer, and J. Arva, “Performance Assessment of a Pushrim-Activated Power-Assisted Wheelchair Control System, ” IEEE Transactions on Control Systems Technology, Vol. 10, pp. 121-126, 2002.
[7]　G. Ellis, Observers in Control Systems, Academic Press, San Diego, 2002.
[8]　R. C. Hibbeler, Engineering Mechanics Dynamics, Prentice-Hall, Inc., New Jersey, 1998.
[9]　L. Ljung, System Identification Theory for The User, Prentice-Hall, Inc, New Jersey, 1999.
[10]　D. Karnopp, “Computer Simulation of Slip-Stick Friction in Mechanical Dynamic Systems,” ASME Journal of Dynamic Systems, Measurement and Control, Vol. 107, pp. 100-103, 1985.
[11]　S. Nakamura, Applied Numerical Methods in C, Prentice-Hall, Inc., New Jersey, 1993.
[12]　P. S. Carpenter, R. H. Brown, J. A. Heinen, and C. Schneider, “On Algorithms for Velocity Estimation Using Discrete Position Encoders,” 1995.
[13]　R. H. Brown, S. C. Schneider, and M. G. Mulligan, “Analysis of Algorithm for Velocity Estimation from Discrete Position Versus Time Data,” IEEE Transactions on Industrial Electronics, Vol. 39, pp. 594-599, 1992.
[14]　S. H. Lee and J. B. Song, “Acceleration Estimator for a Low-Velocity and Low-Acceleration Regions Based on Encoder Position Data,” IEEE/ASME Transactions on Mechatronics, Vol. 6, pp. 58-64, 2001.
[15]　R. D. Lorenz and K. W. V. Patten, “High-Resolution Estimation for All-Digital AC Servo Drives,” IEEE Transactions On Industry Application, Vol. 27, pp363-368, 1991.
[16]　P. B. Schmidt and R. D. Lorenz, “Design Principles and Implementation of Acceleration Feedback to Improve Performance of DC Drives,” IEEE Transactions on Industry Applications, Vol. 28, pp. 594-599, 1992.
[17]　K. Ohnishi, M. Shibata, and T. Murakami, “Motion Control for Advanced Mechatronics,” IEEE/ASME Transactions on Mechatronics, Vol. 1, pp. 56-67, 1996.
[18]　B. C. Kuo, Automatic control systems, 7th ed, Prentice-Hall, 1997.
[19]　C. P. DiGiovine, R. A. Cooper, M. M. DiGiovine, M. L. Boninger, and R. N. Robertson, “Frequency Analysis of Kinematics of Racing Wheelchair Propulsion,” IEEE Transactions on Rehabilitation Engineering, Vol. 8, pp. 385-393, 2000.
[20]　J. S. Miller, “The Myotron – A Servo-Controlled Exoskeleton for The Measurement of Muscular Kinetics,” Cornell Aeronautical Laboratory Report VO-2401-E-1, 1968.
[21]　S. D. Algood, R. A. Cooper, S. G. Fitzgerald, R. Cooper, and M. L. Boninger, “Impact of a Pushrim-Activated Power-Assisted Wheelchair on the Metabolic Demands, Stroke Frequency, and Range of Motion Among Subjects with Tetraplegia,” Arch. Phys. Med. Rehabil., Vol. 85, pp. 1865-1871, 2004.
[22]　羅浚彬，直驅式電動汽車雙馬達之電流分佈控制，碩士論文，國立台灣大學機械工程學系，民國92年。
[23]　邱奕範，命令及摩擦力前饋控制於工具機之研究，碩士論文，國立成功大學機械工程學系，明國90年。
[24]　吳楷聲，蔡明祺，伺服系統之實用參數設計，2003中華民國自動控制暨生物機電系統控制與應用研討會，B1-014，2003年。
[25]　邱毓賢，數位式行動輔具控制器設計及測試，碩士論文，國立成功大學醫學工程研究所，民國88年。
[26]　工業技術研究院機械工業研究所，PMC32韌體開發技術手冊，工業技術研究院，2001年。
[27]　張智星，MATLAB程式設計與應用，清蔚科技股份有限公司，新竹市，2001年。
[28]　洪維恩，數學運算大師MATHEMATICA 4.0，碁峰資訊股份有限公司，台北市，2002年。