The circuit built is an integrated platform for each component of the bioreactor. We develop a board with female header pins that allow the user to plug in an Arduino, three stepper drivers and other required components onto the circuit. This was done mainly to incorporate the idea of re-usability. If you burn or short circuit one of the electrical components and it gets destroyed then you can plug it out and use a new component in the circuit rather than discarding the whole board. The circuit receives power from two different sources - 5 volts from the arduino and 12 volts from an external source. The communication of the circuit board to the software is done via Serial Communication through USB port of the microcontroller.
Specifications :
- Board Length - 100 mm
- Board Breadth - 80 mm
Schematic
Circuit Protocols
We use a definite set of ports of the arduino for each one of our devices.
Arduino Pins Protocol
| Pins |
PWM |
Name |
Device
|
| D2 |
No |
F_Enable |
Feed Pump
|
| D4 |
No |
Valve Transister |
Valve
|
| D3 |
Yes |
OD Transister |
OD
|
| D6 |
Yes |
Stirer Transister |
DC Motor
|
| D7 |
No |
A_Enable |
Aeration Pump
|
| D9 |
Yes |
A_Step |
Aeration Pump
|
| D10 |
Yes |
H_Step |
Harvest Pump
|
| D11 |
Yes |
H_Enable |
Harvest Pump
|
| D12 |
No |
Direction |
All Pumps
|
| D13 |
No |
A_Step |
Aeration Pump
|
Power Supply
The Arduino is powered using the computer. There always remains a possibility to use the Vin ports to switch the circuit ON without the USB but using the power supply board.
The Pumps use a power supply of 12V supplied by a switching adapter (Model Number : HNP24-120)
Input : 100-240 VAC, 50/60 Hz 0.8 A
Output : 12 Volts, 2000 mA
Files
All files to print the circuit can be found here Aachen_MainCircuitzip