Vermes
Advanced Member level 4
It is an useful device for everyone who want to measure their heart rate, for example while riding a bike. This simple device provides the following parameters displayed all the time on the monitor:
- heart rate
- % of maximum heart rate
- the number of calories burned
- the amount of time spent in each of the three levels (fat burn, fitness, performance)
The construction is simple and with a small amount of components. It was made on Arduino. Transmitter module is BM-CS5SR, and the receiver is BM-MM5. Both are available at: LINK. Receiver BM-MM5 is available in two versions: SPI and UART – you should choose the second one.
Hardware:
Schematic of the system is very simple and consists of only few components:
- Atmega324 (to which the Arduino bootloader was uploaded to, and then you only have to upload the executive code)
- receiver module BM-MM5
- three buttons: UP, DOWN, ENTER/ACK
- components which allow the receiver to „talk” with the microcontroller: 3,3V voltage regulator, two transistors for conversion of the voltage levels RX and TX, and some resistors and capacitors)
Software:
90% of code is the display menu. The rest is responsible for the heart rate receiver, calculating showed values and the display support.
Housing was made of plexiglass.
Pictures of the device:
List of components:
- transmitter
- receiver
- Atmega324
- LCD display
Link to original thread (useful attachment) - Bardzo prosty pulsometr
