Structural Design And Simulation On Stationary Digital Breast Tomography System

Breast cancer is the most common cancer among current Chinese women.Our breast cancer mortality has been high, which will reduce breast cancer mortality, the key is early detection, early diagnosis and early treatment.Application of digital breast tomography system, improve early breast cancer detection rate has improved significantly.Scanning the current system is a single hot cathode X-ray source is fixed to the rotating frame, set along the circular path movement to achieve multi-angle X-ray scanner.Motion artifacts generated by the system is mechanical movement, will reduce the spatial resolution of the image, not conducive to the image reconstruction;Hot cathode X-ray source emission mechanism of latency, will extend the scan time and increase patient radiation dose.This article was improved the scanning mode of current digital breast tomography system,using multibeam X-ray of field emission based on carbon anotubes cathodes.The multi-beam field emission X-ray source has a compact structure, the transient response and other advantages,through programmable control the distribution of the different positions of the X-ray source to replace multi-angle static scan scanning movement,can eliminate motion artifacts and improve time resolution,thereby reducing the radiation dose.The main contents of this paper:(1)For stationary digital mammography system works,designed the new breast oppression by using virtual prototyping method combination with the ergonomic,completed digital still breast tomography system architecture design, transmission design and selection calculation.(2)By using three-dimensional electromagnetic simulation software CST particle studio completed single-beam X-ray source simulation to obtain the optimal focusing electrode 1 pore structure, pore size, thickness and anode voltage of focus area for mammography.Referring to the single-beam simulation results to determine the optimal distance between two adjacent X between the radiation source, developed a multi-beam X-ray source field emission electron gun.(3)Mechanical properties and dynamic properties of column structure had been researched which used the finite element analysis software of ANSYS. Used point mass treatment for verification of height adjustment conditions.The results showed that the strength and natural frequency of the column meet operational requirements.(4)Based on topology optimization design method for material removal pillar structure.Second design of column quality decreases 18.61%, the natural frequencies are increased, reaching the post of lightweight design goals.(5)Finite element analysis of stationay breast tomography system model by ANSYS, the results show that the system structure designed to meet the requirements.