A handheld 3D scanner is a portable 3D scanner that can be used to capture 3D data on the surface of a subject using handheld scanning.

Technical background generated by handheld 3D scanner

Three-dimensional scanning technology was born to solve the design and manufacturing needs of the industrial field. Its mainstream technology has developed to the fourth generation from the present to the present. The first generation is contact measurement technology, the second generation is line laser scanning technology, and the third generation is structured light scanning technology. Compared with the previous two generations, the third generation technology has improved significantly in terms of efficiency, cost and use, and has therefore been promoted worldwide. However, with the further improvement of the requirements of the efficiency and ease of use of 3D scanning, the inherent flaws of the technology have become obsolete, resulting in four generations of 3D scanning technology - handheld 3D scanning.

Handheld 3D scanning technology, which uses a line laser to acquire a point cloud of an object surface, and uses visual markers to determine the spatial position of the scanner during operation. Handheld scanning has the advantages of flexibility, efficiency, and ease of use, representing the future direction of development. Handheld scanning has maximum flexibility, but since the movement of the hand is arbitrary, how to accurately and in real time determine the spatial position of the hand at any time becomes the core issue of the technology. Spatial positioning technology based on visual marker points is the key to solving this problem. At present, there are only two masters of the technology in the world, one in China (Hualang 3D) and the other in foreign companies.

Handheld 3D scanning technology advantages

The general three-dimensional handheld scanner series uses traditional dot marking for visual positioning. Since visual positioning requires an "ideal point" - that is, no size, the center of the circle is actually used, and the coordinates of the center of the circle are fitted by extracting the boundary of the circle. However, due to the existence of perspective projection and lens distortion, the boundary of the dot in the image is not a circle, nor an ellipse, but an irregular free shape, so there must be a deviation between the fitted center and the true center.

Unlike other handheld 3D scanners, we have abandoned traditional dot markers and used a new visual marker that does not cause bias - corner markers. The corner points of the corner mark are similar to the intersection of the black and white checkerboard, which satisfies the requirement of "ideal point" - that is, there is no size. When extracting, we get the coordinates of the corner point directly, instead of getting it by fitting, so there is no deviation from the real corner point. This not only improves the positioning accuracy, but also ensures the accuracy and reliability of subsequent photogrammetry.

Compared with dot markers, the extraction of corner markers is much more complicated. If it is implemented by software alone, it is difficult to achieve real-time smooth scanning. To this end, we have incorporated the corner extraction algorithm into the hardware chip, which not only ensures the smoothness of scanning, but also greatly reduces the requirements for computer configuration. Our handheld scanner works fine with a normal computer. The interface used is a USB interface. See the computer configuration for details. Other companies' handheld scanners use software for visual positioning calculations, so the requirements for computer configuration are high, and the 1394 interface must be used to meet the transmission of large amounts of data.

Handheld 3D scanning technology company representative - Hualang