- 學位論文
應用於電動式輪椅斜坡迴轉之翻覆分析與控制方案
Turnover Analysis and Control for On-slope Maneuvering of Electric Wheelchair
摘要
本論文研究電動輪椅斜坡迴轉之翻覆分析，並據此提出控制方案。永磁同步馬達可應用在傳統式手動輪椅，作為輪椅前進的動力。由於輪椅在使用上受制於環境的限制，特別是輪椅在斜面上之迴轉行為。本論文主要考量輪椅在斜坡上運動時，重力會產生平行於斜坡之下滑力而影響平衡，以及輪椅在斜坡迴轉時，產生離心力，影響輪椅在斜坡運動之平衡，因此，輪椅可能失去控制而有翻覆失速的危險。本研究首先分析輪椅系統運動狀態，藉以得到輪椅在迴轉轉速之安全範圍，據此提出輪椅速度控制之方案。 由於其成本低及控制簡單，前人文獻上多採用直流馬達於電動輪椅上，通常搭配減速機構，然而此系統使用上機身相對笨重，且直流馬達電刷會產生火花，必須定時清理，效率也比交流馬達差。本研究使用輪轂式永磁同步馬達為載具，並以向量控制方式驅動。由於機構上的限制，無法加裝減速機及編碼器，在速度控制只能使用霍爾感測器所產生的訊號作為速度回授，因此增加馬達低速控制的困難度。本研究以MATLAB建立馬達模擬環境，使用一TI之數位訊號處理器TMS320F28035作為實驗時馬達驅動的控制訊號，分別獨立控制兩顆永磁同步馬達並傳動輪椅。實驗部分包含平地的基本運動測試，斜坡則是測量輪椅迴轉上坡及下坡之穩定性。
並列摘要
This research presents the use of power permanent magnet synchronous motors. This is used as power of traditional manual wheelchairs. Since the wheelchair is subjected to environmental restrictions, especially for wheelchair rotating on the slope. A number of literature focus on maneuvering of electric wheelchairs on the slope and doing suppression control. This article considers wheelchair movement on a slope. The gravitational force generated parallel to the slope of the decline, affects the balance of the wheelchair. Further, when wheelchair is turning on slope, it will produce centrifugal force. It also affects balance of the wheelchairs and increases the risk of loss of control and overturn. Wheelchairs dynamic analysis using Newton method to reach the rotary speed, thus realize the importance of controlling speed of wheelchairs. Due to low cost and simple control strategy, DC motors are widely used in deceleration mechanism. However, this mechanism is bulky and relatively inconvenient. Also brushes of DC motors should be cleaned regularly to use efficiently. Therefore to avoid these difficulties, AC motor is chosen. The hub permanent magnet synchronous motor (PMSM) is used in this experiment, and driven in Vector control, also known as field-oriented control. Because of structural constraints, deceleration mechanism and encoder can’t be installed. Speed control only depends on Hall signal that increases the difficulty of low speed control. The simulation of the motor drive system is based on MATLAB environment. Further experiment and motor driven control algorithm is conducted using 28035-based motor driven DSP controller. Here two PMSMs are controlled using one DSP.