Research On Electrical Impedance Tomography Based On Embedded System

Electrical impedance tomography technology is a new type of imaging technology developed in recent years.The principle is to place a number of electrodes around the boundary of the measured object,measure the boundary electrical information of the measured object in a non-invasive way.The electrical characteristic distribution inside the field of the measured object is reconstructed by using a specific electrical impedance reconstruction algorithm to realize the visual measurement of the measured object.The electrical impedance measurement system mostly uses the single chip computer,FPGA,DSP,PXI bus controller as the data acquisition core,and uses the communication interface such as serial port,USB port and network port to upload the electric information of the measured object to the computer,finally realize the data processing and The reconstruction of the internal image of the field to be measured.In the current device intelligent portable development needs,ARM processor with a higher processing speed,smaller size,better function for the future development of electrical impedance imaging technology provides a new direction.The main research work of this subject is as follows:1)The 8-electrode circular field simulation model is established by using comsol simulation software,and the problem of the imaging object in the field is analyzed;2)The embedded cross-compiling environment is completed.Embedded Linux system transplantation;3)prepared a high-precision impedance measurement chip AD5933 IIC driver and used C++ library based on the QT library impedance analysis GUI interface;4)the success of the impedance analysis GUI interface ported to the Feiling embedded OK6410 platform,And use the touch screen for human-computer interaction;5)the embedded electrical impedance tomography system collect the data,and analysis the data;6)embedded development board to collect the impedance data transmitted to the computer,and Image Reconstruction of 8-electrode Circular Field by Image Reconstruction Algorithm.The system uses a highly integrated and high precision AD5933 impedance measurement chip,the processor based on the ARM architecture SAMSUNG S3C6410,the operating system using embedded Linux2.6.39,and the use of QT to develop the impedance analysis GUI interface as the user interface.By loading the IIC driver with SecureCRT terminal and running the data acquisition instruction,you can collect the boundary impedance information of the measured object.After the system measurement is finished,the curve of the boundary impedance information of the measured object can be drawn by using the impedance analysis GUI interface,and the change characteristic and regularity of the boundary impedance of the measured object can be judged by the shape of the curve.In addition,the network communication through the embedded development board can measure the boundary impedance data transmitted to the computer for the final image reconstruction.