Design And Modification Of An ARM Based Imbedded Electrical Resistance Tomographic Measuremect System

Resistance tomography as an imaging techinique has the virture of non-invasive,zero radiation,online measurement and is widely used in the geological exploration,industrial process monitoring and imaging and so on.It is a modern industrial process imaging and inspection technology.The main content of this paper is that,according to an existing laboratory based prototype ERT system,it describes some of the modification work performed on the system to improve its operation performance.These works are: a low-level driver developed on the dual-access ram(DARAM)to enhance the reliability of data communication between the DAS controller and the hosting imbedded controller(ARM9);a mode of control on data communication between the DAS and the hosting controller;a flexible imaging mechanism based on the mode of data communication,and all relevant works on packing all system hardware into a portable box.The idea of flexible data imaging is validated by real time measurement in this research and proved to be feasible.The main contents include:1.Using the mailbox hand-shaking communication concept to establish the communication between the DAS controller and hosting ARM controller.With such a hand-shaking mechanism,the conflict on using data memory of the DARAM by the two controllers connected to it is effectively avoided,thus ensuring the reliability and stability of data communication which in turn enhancing the reliability and stability of the imaging.2.Implementing a new imaging mechanism by a flexible data updating scheme.By reducing the updating date in the next image slide effectively reduce the time interval between the two images,thus in addition to improving the imaging rate of the system it also improves the image resolution in the axial dirction under given flow velocity.The concept of new imaging mechanisim is validated and proved feasible3.Thourouly re-designs the underlying device driver for the DARAM,which enables the ARM9 controller to perform a flexible but reliable control over the use of DARAM.4.Redesigns the PCB for data acquisition and connection,packing all hardware into a portable box after redebugging the entire system.