摘 要: 根據投影機和照相機的光學成像原理,借用雙目測量系統的標定方法搭建了一套測量精度高、標定過程自動化的基于數字條紋的三維形貌測量系統,并采用最新的相位展開技術用較少的條紋圖像完成相位展開,通過對人臉石膏像進行測量實驗,驗證了系統模型和測量方法的正確性。
關鍵詞: 數字條紋; 標定; 形貌測量; 相位展開; 三維重構
中圖分類號: TN710?34; TP391.4 文獻標識碼: A 文章編號: 1004?373X(2013)23?0099?04
Research and implementation of 3?D profile measurement technique
based on digital fringe projection
LONG Jia?le1,2, CHENG Rui1, ZHANG Jian?min2
(1. Department of Electronic and Information Engineering, Huazhong University of Science and Technology, Wuhan 430074, China;
2. School of Information Engineering, Wuyi University, Jiangmen 529020, China)
Abstract: According to the principle of optical imaging of projector and camera, a three?dimensional profile measuring system based on digital fringe is constructed by using the calibration method of binocular vision measuring system, which has the advantages of automated calibration and high accuracy. The newest phase unwrapping method which uses less fringe patterns is employed. Experiments on a plaster human head model are conducted to confirm the system model and the measuring method.
Keywords: digital fringe pattern; calibration; profile measurement; phase unwrapping; three?dimensional reconstruction
0 引 言
隨著各種光學器件和技術應用于照相機和投影機,非接觸式光學測量方法得到快速發展,并廣泛應用到工業自動檢測、逆向設計、生物醫學、文物復制、人體測量等眾多領域中[1]。光學三維測量技術按照成像照明方式的不同通常可分為被動三維測量和主動三維測量兩大類。
其中主動三維測量技術采用不同的投射裝置向被測物體投射設計好的結構光,并拍攝經被測物體表面調制而發生變形的結構光圖像,然后從攜帶有被測物體表面三維形貌信息的圖像中計算出被測物體的三維形貌數據[2]。傳統的系統大都采用理想的數學模型,需要使用參考平面。這種測量系統不能得到精確的三維坐標;硬件的位置關系要求十分嚴格,可操作性差,標定過程麻煩。
基于數字條紋投影的三維形貌測量技術是目前很有發展前景的非接觸式主動測量,它在獲取物體表面三維數據時一般分為兩大步驟:先通過對變形條紋的分析獲取相位圖,再對相位圖進行展開操作。……