Design of the multichannel measurement system for strain gauge sensor evaluation

Abstract

This paper deals with design of multichannel measurement system for strain gauge sensor evaluation in laboratory of mechanical engineering. Device is based on 8-bit Freescale microcontroller MC9S08GB60 which is due its properties intended for general purpose applications. Device implements modular hardware design enabling easy functionality expansion in future demands. This is fulfilled by dividing of the whole measurement system to main board and input / output eventually measurement modules. Main board of the device contains master microcontroller, USB communication interface, power supplies and interface for expansion cards. Modules for strain gauge sensor evaluation consist of amplifier with selectable gain followed by 4th order Bessel low-pass filter eliminating ripple in analog signal and finally 12-bit analog-to-digital converter connected via serial peripheral interface (SPI) and other control signals with main board. Communication with supervision system is provided by USB interface which is recognized as standard serial port in host operating system.