采用镜头套筒进行水下数字图像测量

Underwater digital image measurement using lens sleeves

目的研究适用于水环境的生物材料力学测试技术。方法基于数字图像相关法(digital image correlation,DIC)设计独特的镜头套筒,避免水下摄影的畸变,并将该技术应用到鱼鳞的力学性能测试中。结果水槽平移实验表明:使用镜头套筒可以有效减小水下测量的误差,测试精度可靠。鱼鳞的力学性能测试表明:鱼鳞不同部位的力学性能具有明显差异,而失水后这种差异的显著性降低。结论设计的镜头套筒能够有效地运用到图像采集系统中,利用DIC技术实现水下生物材料的力学测试。

Objective To explore the mechanical testing technique suitable for biological materials under water en- vironment. Methods Based on digital image correlation （DIC） method, the unique lens sleeves which can avoid the distortion caused by underwater photography was designed, and this technique was applied to determining mechanical properties of the fish scales. Results The experiment on translation of the water sink indicated that the use of the designed lens sleeves could effectively reduce errors for underwater measurement with high preci- sion; the mechanical testing on fish scales showed that different regions of the fish scales had obviously different mechanical properties, but the differences induced by regions of the dehydrated fish scales were significantly re- duced. Conclusions The designed lens sleeves in this study can be applied to image acquisition effectively, and determination of mechanical properties of the biological materials under water environment was achieved using DIC method.