創新式具多彩表面三維形貌量測技術與系統之研發

Development of Innovative 3-D Multi-color Surface Profilometry and Its system

莊馥豪(Fu-Hao Chunag)

指導教授 ： 陳亮嘉

國立臺北科技大學/機電學院/自動化科技研究所/碩士(2010年)

摘要

本論文提出一種創新式具多彩表面三維形貌量測技術，用以量測具多彩表面物件之三維形貌具多彩表面物件，可有效提升具多彩表面物件三維輪廓量測的精密度。目前大部分應用於三維輪廓量測的演算法如相移法、傅立葉等量測技術，絕大部分均以投射黑白正弦結構光為主，利用灰階影像感測裝置取像為主，一般均受限於待測物表面顏色散射的影響，以致於量測結果不穩定，其量測條件要求被測物件表面為標準白色，由於各式各樣的物件不只侷限於單一顏色，不同顏色的待測物具有不同的反射特性，故上述方法並不適用具多彩表面物件之三維形貌量測需求。 因此，本研究提出傅立葉演算法搭配三通道彩色CCD，針對適合待測物的彩色條紋結構光進行傅立葉轉換，使三維量測具有多彩物體形貌之即時三維量測與重建能力，不只受限於單一顏色之待測物。 本研究之實驗利用不同彩色標準塊來驗證系統量測準確(accuracy)，並分析不同的環境振動頻率對量測結果之影響。同時，本研究亦採取以實際量測實例，以驗證本研發技術之實用性。根據三維實例量測結果之驗證，針對不同彩色標準塊規投射結構光並選取適合待測物的色彩條紋，量測重覆度精度(Precision)之最大誤差可控制在全高量測範圍之百分比2.48%以內。

關鍵字

自動化光學檢測(AOI) ； 動態量測 ； 快速傅立葉轉換 ； 三維形貌量測 ； 三維輪廓重建

並列摘要

In the research, a novel 3-D vision method with its optical system is developed to measure and reconstruct shape and color information of objects having arbitrary surface colors for in-field robots. A novel multiple-color fringe Fourier Transform Profilometry (FTP) is developed employing an encoded RGB (red, green, blue) color fringe pattern for measuring objects at a 3-D measuring speed up to the highest frame rate of CCD image acquisition. The sinusoidal color fringe pattern is encoded to form a unique color pattern for projecting onto the object surface, and its reflected deformed fringe image is taken by use of a 3-chip color CCD camera and rapidly processed by the developed FTP method having a novel bandpass filter. To reconstruct a surface with arbitrary surface colors, an innovative strategy is developed to identify a color channel of the detected fringe pattern having the best modulation transfer function (MTF) for retrieving accurate phase map of the object’s profile. The experimental results have verified the feasibility of the proposed method in acquiring accurate 3-D maps at a high speed.
The experiment in the research employs several standard step heights having various surface colors to verify the accuracy of measurement system and analyze the influences of surrounding vibration frequency on the measure results. Besides, the research investigate the measured results of some real objects to verify the feasibility of the developed method. According to the verification results of 3-D measurement, the measurement repeatability can be controlled within 2.48% of the overall measured depth range.

並列關鍵字

Automatic optical inspection (AOI) ； surface reconstruction ； Fast Fourier Transform (FFT) ； full field ； surface profilometry

參考文獻

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