Design and implementation of an impedance analyzer based on Arduino Uno : A pilot study of bioelectrical impedance analysis

Sammanfattning: Electrical bioimpedance measurement is widely used today for monitoring body condition. The applications include and go beyond, body composition assessment, nutritional status evaluation, and cancer detection. The modalities for interpreting the impedance information have also developed quickly over the recent decades from single frequency bioimpedance analysis to spectrum and to images. Bioimpedance is measured by computing the relationship between voltage and current. In a current based bioimpedance measurement system, the stability of current source has a large influence on the performance of the system. This thesis compared three different voltage controlled current sources: enhanced Howland circuit, load-in-the-loop circuit driven by a current conveyor and double operational amplifiers circuit. These circuits were simulated in Multisim and manufactured into prototypes and tested in lab. Effort has also been made to generate and collect signals with digital-to-analog convertor and analog-to-digital convertor. They were controlled by Arduino Uno and impedance was analyzed in Matlab.