Research On Key Techniques Of Optical Positioning In Surgical Navigation Based On Zynq

Surgical navigation system(SNS)accurately matches the preoperative image data of the patient with the intraoperative anatomy,which can provide doctors with the position and direction information of the surgical instrument relative to the surgical target during the operation,guiding the operation in real time.The positioning device is the core part of SNS because its real-time and accuracy performance of the tracking directly affects the safety and accuracy of SNS.Near-infrared optical positioning technology based on the principle of binocular vision is widely used in the field of surgical navigation because of its high precision and convenient operation.However,domestic optical positioning equipment mainly relies on imports and lacks of independent innovation and technical support.Therefore,in order to independently develop a high-precision optical positioning system,it is necessary to study the key technologies such as system hardware design,synchronous acquisition of camera image,sub-pixel coordinate extraction of markers and real-time transmission of data.In order to solve the key problems mentioned above,this paper uses Zynq as the core processor.Through the optical positioning hardware system design and the software and hardware collaborative design of Zynq platform,the real-time tracking and positioning of near-infrared markers was realized.The main research contents of this paper are as follows:(1)The optical positioning hardware system was designed,and the module of the system was divided and designed according to the requirements of optical positioning technology.The chip selection and hardware circuit implementation are completed according to the functional requirements of the module.(2)The high-synchronization near-infrared camera image acquisition module was designed.The near-infrared camera can effectively restrain the interference of visible light on image marker extraction,and effectively avoids the pseudo-matching problem of markers through high-synchronization image acquisition control.(3)High-speed image marker extraction was implemented,the real-time image marker recognition and sub-pixel coordinate calculation are realized by using programmable logic resources of Zynq platform.(4)A high-speed data transmission scheme was realized,which realizes high-speed transmission of image and marker point coordinate data based on three communication modes included Ethernet,USB and Wi-Fi,which satisfies the communication requirements in different scenes.The experimental results show that the standard deviation of the positioning accuracy of the surgical navigation optical positioning technology proposed in this paper is within 0.15 mm,the processing speed is up to 60 pfs with extremely high synchronization of image acquisition,which meets the application requirements of surgical navigation.