Orlando Hoilett has built his new biomedical Arduino 101 shield: Biomed Shield, in order to allow students, educators, and hobbyists to learn about bio-medicine by monitoring heart rate, temperature, and other physiological metrics.
To build this shield he used the following components:
- AD5933
- MLX90614
- Microchip Rail-to-Rail Input/Output Dual Op-Amp
- MAX30101: a specialized integrated circuit that is able to perform reflectance photoplethysmography
- Photocell
- Thermistor
- AD8227
Orlando measured heart beats using transmission photoplethysmography using MAZ30101, where a light shines through an extremity such as a finger and a detector measures the amount of light that passes through. When the heart pumps blood through the body, a momentary increase in blood volume in the fingers happens. As a result, the amount of light that passes through the finger changes with this changing blood volume and is detected by the photodetector.
Bioimpedance is can be another class of bioelectrical measurements where we measure the impedance of the body instead of measuring the electrical signals produced by the body with the help of AD5934 impedance analyser chip. He is also measuring body temperature with the MLX90614 and measuring the amount of light using a CdS Photocell.
Orlando built this shield for education purposes not as a medical device, and his work on this shield is still in progress. Follow his project on hackster.io to know more details and updates. You can check source files at Github.