Fast 3D shape measurement using structured light projection for a one-directionally moving object

In this study, a fast coded structured light projection method was dedicatedly designed for inspecting three-dimensional shapes of one-directionally moving objects at a high frame-rate, simply by projecting a single time-invariant coded structured image that involves multiple structured slit-light patterns at different lines. Most coded structured light projection methods are unsuitable for measuring high-speed moving objects because of light projection of time-variant patterns at different frames. Our method can accurately obtain three-dimensional shapes of moving objects for inspection, without synchronization errors, if they are conveyed in one direction, such as on factory conveyor lines. We also developed a prototype system for three-dimensional shape measurement based on a high-speed vision platform, which can process 512×96-pixel images at 10,000 fps, and evaluated its effectiveness from experimental results for quickly moving objects measured in real time at 10,000 fps.