SoftwareSeveral software applications have been written and used to operate the hardware described in the previous section. This section is a description of the software used in the research. A software application that controlled the positioning system, waveform generator, power, and data acquisition from the CPD sensor was written in a LabView (from National Instruments) graphical programming environment. The Labview environment was chosen due to its ease of use in designing the graphical user interface and the availability of all necessary libraries and drivers for Labview from the hardware manufacturer. Labview has provided hundreds of built-in libraries for advanced analysis and data visualization. The written application communicated with the DAQ PC card and the indexer ISA card installed in the PC to control the input data from the CPD sensor and its movement on a sample surface. A graphical user interface was also provided to control the hardware, view and monitor signals, and also set measurement parameters. The application was used to postprocess the data and display the surface scan results in 2D and 3D views. A schematic diagram of the application is displayed in Figure 3.17. Positioning System Software The positioning system manufacturer has provided libraries of software routines to help develop programs for the 6400 Series motion controller. These libraries have been compiled into Labview to make it usable in this environment. Figure 3.17: Schematic diagram of the Labview application. Using routines from compiled libraries, the application communicated through the PC's ISA card with the indexer to control the speed, direction and acceleration of the CPD sensor's movement.... middle of paper...[7] Kelvin, "Contact Electricity of Metals", Philosophical Magazine v46 (1898), p82[8] WA Zisman, "A New Method of Measuring Contact Potential Differences in Metals", Review of Scientific Instruments, v3 n7 (1932), p367[9 ] E. Zanoria, S. Danyluk, A. Zharin, C. Bhatia, "Measurements of the contact potential of hard disk drive surfaces in humid environments", Journal of Vacuum Science & Technology A: Vacuum, Surfaces, Films v14 n1 (1996), p52[10] Hamall, K. "Non-contact measurement of wear-induced changes in surface potential", MS Thesis, Georgia Institute of Technology, Atlanta, 1996[11] Watt A., "Fringe Field Corrections in nvCPD Applications", MS Thesis, Georgia Institute of Technology, 2004.[12] WRSmythe, Static and Dynamic Electricity, 2nd ed., McGraw-Hill, 1950[??] Landau LD, Livshits EM, “Electrodynamics of Continuous Media”, Moscow: Nauka, 1982