目前視障人士最普遍所使用的導盲工具是白手杖(White Cane)，以之去觸碰地面或是物體以確認前方是否可以行走以及障疑物的位置，而手杖不可及的地方則一概無從得知。目前另一種可行的導盲方式是使用導盲犬，但與全台五萬名盲胞的數目相比較，導盲犬的數目是相當稀少，至今亦是如此，原因是導盲犬的挑選訓練極為不易且成本昂貴，並有壽命的問題，以致導盲犬的使用並不普及。所以當下所需的是一套能協助視障人士的電子導盲系統，有效且即時地改善他們的生活，開發使用便利又成本低廉的導盲輔具是相當重要且刻不容緩的。目前所被使用的導盲輔具以超音波偵測物體為主，但此類型的輔具多必須要使用者主動以超音波偵測障礙物，而非輔具本身主動偵測並告知使用者行走的相關資訊，於是使用者只有在面臨障礙物時才被輔具所引導閃避，並沒有自主選擇行走路徑的能力。 本論文中提出以影像處理的方式，切割出由使用者腳下所延伸出的地板區塊，再經由影像與實際空間的座標轉換，得到路面延伸的寬度以及長度此項路長資訊，對視障人士而言是最迫切需要的資訊，以達到即時解決使用者-「我能走的路延伸多遠? 這條路有多寬? 」的疑惑。藉由此初步的研究，即能令目前導盲的輔具化被動為主動，讓視障人士的行動更為自由。 The most pervasive travel-aid for the blind is the White Cane, which only allows them to ensure that the path is clear and to locate any possible obstacle by using it to touch the ground and objects. The rest of the world beyond reach remains unknown to them. The other option for a blind person to get around is by the help of a guide dog. However, the present population of the blind in Taiwan seriously outnumbers the existing guide dogs. A guide dog training program is very selective as to the dogs to be trained, and it costs a lot of time and money to train while the lifespan of a guide dog is rather limited. As a result, the use of guide dogs is not very popular. Therefore, it is crucial to develop an easy-to-use and cost-efficient electronic guiding system to improve the lives of the visually disabled. At present, a large portion of existing guiding aids uses ultrasonic to detect objects. But instead of actively detecting the surroundings, users need to detect objects by themselves and then avoid whatever possible obstacles. They are not able to choose the path according to their will since this kind of tools only provides passive guidance. In the thesis, we proposed a travel-guide which requires a low-cost web camera and an accelerator circuit. First, we use a segmentation algorithm to segment the floor region from the image captured by the web camera. By the use of the tilting angle measured from the accelerator circuit and a transformation formula we are able to gather information about the width and length of the floor. These two kinds of information are the most critical information for the blind while walking. The information answers their most urgent question about “how wide is the road and how far can I go?” This research explores the ways to help the blind to navigate more actively and be able to move as if they can see. Experiments were conducted to test the performance of the proposed travel-aid.
