Design and Implementation of a Real-Time Programmable Multi-Channel Data Acquisition System for Sensing Applications

The purpose of the following project is to create a general purpose data acquisition system for use in sensing applications. As a proof of concept, the system is configured to interface with a biological subject through electromyographic surface electrodes. The signals of interest are arm and hand contractions. The overall objective established for the fall was to construct a rudimentary system prototype. The intention was to test amplification of low frequency signals and allow for single and dual channel data acquisition that is transmitted to a user interface via serial connection. The interface serves to display the acquired signals in real-time waveform plots. In order to achieve the quarter goal, a few methods of design and engineering were implemented. SPICE analysis was used to assist in the selection of a low-frequency, small signal amplifier. The rest of the components were selected based on currently available commercial circuits. The control system is centered around an Arduino microcontroller and the user interface was developed in Python. Finally, oscilloscopes and multimeters were used for laboratory testing of the system components. The work of this quarter has resulted in the finalization of part selections, testing of individual chips, and the trial of a single channel system. The code to the control system has also been finalized and the user interface can display two live waveforms on a host computer. For this quarter, the goal is to elaborate on the current design to allow wireless transmission of live data through four channel acquisition.