“Heart Beat Sensor” sounds very complicated to be made.But it’s not the reality, it is the simplest medical device to make at home using very few components.
|Heart Beat Sensor|
- Proximity Sensor
- LM 358 IC
- 4.7uF and 100nF Capacitors
- 47k,6.8k,680k, and 1k resistors.
- Some LEDs.
- First, let us discuss the connection of the circuit.
- First, we need to connect the proximity sensor with the transmitter in forward bias and receiver in reverse biased.
- After that fed the signal from the receiver to High Pass Filter.
- Than amplify this signal by feeding the signal into Non-Inverting Amplifier.
- The output of the amplifier will be pulsing proportional to a heart beat.
- If we want to feed the signal into a controller, then we will require an additional buffer amplifier.
Now, discussing some theory of this circuit. The logic behind this is that when our heart beats, the blood circulates in our body. Due to this, there is minute volume change of blood on our index finger. Hence when we place our finger on the proximity sensor, that sensor senses that volume change and gives signal accordingly.