Abstract: A digital image measurement device and method for the surface deformation of specimen based on sub-pixel corner detection is disclosed. This digital image measurement device is composed of a new type of image pressure cell, a complementary metal-oxide-semiconductor (CMOS) camera, a camera bracket, a flexible lens hood, a computer and matching measurement software. This method discretizes the specimen into several four-node finite elements by printing grids on the specimen and takes corners of the grids as the nodes of the finite elements; tracks the deformation of the feature points in real time by edge detection and corner detection based on sub-pixel; captures the deformation of the whole surface of the specimen by the two flat mirrors which are at an 120° angle behind the specimen; achieves the observation of the deformation of the whole surface by conducting splicing and error correction on the three images.

Abstract: A digital image measurement device and method for the surface deformation of specimen based on sub-pixel corner detection is disclosed. This digital image measurement device is composed of a new type of image pressure cell, a complementary metal-oxide-semiconductor (CMOS) camera, a camera bracket, a flexible lens hood, a computer and matching measurement software. This method discretizes the specimen into several four-node finite elements by printing grids on the specimen and takes corners of the grids as the nodes of the finite elements; tracks the deformation of the feature points in real time by edge detection and corner detection based on sub-pixel; captures the deformation of the whole surface of the specimen by the two flat mirrors which are at an 120° angle behind the specimen; achieves the observation of the deformation of the whole surface by conducting splicing and error correction on the three images.

Abstract: Disclosed is an intramedullary nail and a method for embedding and extracting the same through which the problem of having difficulty to correctly determine the position of the intramedullary nail is solved, and the present invention has the following advantages: a correct and rapid determination of the position of the extracting incision, a small incision, a small hurt, a low infection rate, and a quick healing. The intramedullary nail comprises a nail main body; an end cover connected with a tip of the nail main body; a mark body; and a thread connecting the end cover with the mark body. The method for embedding intramedullary nail comprises embedding the thread and the mark body in subcutaneous soft tissues after the nail main body and the end cover are fixed in a tubular bone. And the method for extracting the intramedullary nail comprises determining a position of the mark body, and incising an extracting incision according to the position of the mark body.