Design Of An ARM Based Embedded Electrical Resistance Tomographic Measurement System

Electrical resistance tomography (ERT) is a kind of process tomography (PT). ERT has advantages of being visualized process result,non-intrusive measurement,non-radiative operation,fast in operation and low in cost. It has a promising industrial prospect for two phase flow applications. After nearly 20 years of development, ERT has gradually shifted to practical industrical applications from laboratory study. According to the requirement of industrial field, the ERT system has been required to be of low-power, portable, intelligent, and compact.The specific work that the author of this thesis has finished in this research is asfollows:1. Adopted an ARM (ARM2440) chip capable of runing WinCE as a core CPU for ERT image reconstruction and display, instead of using a PC. This permits the ERT measuring equipment being smaller and compact, low power consumption, and portable. The use of WinCE as operating system can greatly improve the efficiency of programming. WinCE system has good database, network standard and technical supports, it can be very convenient for the future ERT equipment upgrade on remote access and control.2. Based on the analysis of ERT data transmission requirement, the thesis compares the performance of several common data transmission methods. In this thesis a multi-bus FIFO ram chip is used as a shared storage between the ARM system and the measuring MCU system. The embedded system reserves the UART and USB port in case a connection to PC is needed.3. Ported the PC based ERT algorithm (LBP method) into the ARM based system. Due to the restrictgion of WinCE, the OpenGL ES 2D/3D graphic library cannot be used in the ARM system. Therefore all the functions containing OpenGL has to be modified before running. This work has to be accomplished with the resources supported by WinCE.