非接觸式裂縫量測手機之研發

Non-contact Measurement of Cracks on Smart Phones

本研究發展一非接觸式裂縫量測手機，係整合雷射光點投射定位技術與智慧型手機行動運算技術，在Android手機平台下，已開發出裂縫量測手機的原型機，能讓使用者易於攜帶與量測，具有安全性與便利性。在雷射光點定位方面，本研究提出雙十字螺絲調整法來提供雷射投射之平行機制，並利用手機之感測器來直接量測雷射投射角度；在影像辨識方面，直接在手機上進行雷射光點影像偵測、裂縫影像正交轉換以及裂縫影像辨識，可立即將裂縫的真實長度與寬度量測出來。最後，本研究以單一裂縫案例以及複數裂縫案例來進行系統之驗證與討論，結果顯示，本裂縫量測手機可合理量測遠距離裂縫之長度與平均寬度，其量測誤差可小於5.71%。

The present study has developed a non-contact crack measuring smart phone based on the laser projection positioning and mobile computing techniques. It is very convenient for users to bring it and measure cracks remotely. For the laser projection positioning, a double plus-sign screw adjustment method is proposed to allow the laser projection in a parallel way. In addition, the lasers’projecting angles can be measured directly by the smart phone’s sensors. On the other hand, for the image processing, the laser point recognition, the image ortho-rectification and crack recognition are all directly computed on the smart phone. Hence, the crack measurement can be obtained immediately. Finally, two test cases are conducted to validate the proposed remote crack-measuring system. The results show that this system can measure the crack length and width with sufficient accuracy.