Design and Study of Infrared Optical Positioning System in Surgical Navigation Based on FPGA
|Keywords||Surgical navigation Optical positioning CMOS FPGA SOPC Hardware acceleration|
In recent years , modern medicine, surgery toward the development of a precise , minimally invasive direction , so bring a surgical navigation system . Optical positioning system using a planar array CMOS sensor is compatible with both active and passive tracking , and has the advantages of high accuracy and ease of use , the main direction of development of optical positioning equipment in the surgical navigation system . This thesis, through in-depth study of the positioning principle of binocular vision and embedded hardware system , to build a set of infrared optical positioning system based on FPGA and SOPC system to achieve real-time location and tracking of the signs point in space . The thesis completed work include:  three-dimensional reconstruction of the direct linear transformation (DLT) and limit constraints Plane Array CMOS system of spatial coordinates are given and demonstrated how to use the direct linear transformation method of optical positioning system calibration , as well as internal and external parameters were calculated for each camera .  designed and developed a prototype based on the principle of binocular vision infrared optical positioning system to complete the design of the hardware and software of the system prototype . System development , starting from the most distal of the CMOS sensor , the completion of the image sensor using the FPGA drive design, the center of the mark point extraction . Designed for the convenience of system debugging image cache and VGA display function . In addition, a prototype design the fixed and encapsulation of the mechanical structure for the system . [ 3 ] the problem of inadequate performance for the Nios II processor , use hardware acceleration to improve the rate of three - dimensional solver solutions , positioning system tracking rates have been greatly enhanced , making the signs point solver embedded hardware completed on the platform . [ 4 ] to build a high-precision experiments platform , design and complete system calibration experiments , to obtain a better calibration accuracy . To solve the key issues in the process of calibration experiments image access . In conclusion , the paper special application for locating and tracking in surgical navigation system , the completion of a three-dimensional coordinate space multi- point real - time high-precision positioning technology research and system development . The test results show that the system achieved a sub-millimeter positioning accuracy and a 60Hz refresh rate .