Improved Problem statment
ARBsource has contracted NAU to help them devise a improved potentiostat that can survive in the harsh conditions that the bio reactor creates. Over the course of the year, ARBsource's needs have changed from what they wanted out of this project. Their main problems were that their current design was unreliable and created a lot of noise once it was put onto a PCB (printed circuit board). The potentiostat will need to take in 4 different channels. These channels will monitor the ARBcell's "health" in the system. Since then, ARBsource has wanted the bulk of our hours put into micro-controller to GUI communication.This entails having a working micro-controller that will talk to the GUI and back effectively. The GUI will log and graph the data.
System Requirements/Improvements
Specific System Requirements given to our team by ARBsource
- 5V with an optional external power supply (+/- 10 to 12V)
- Accuracy within 5mV
- Less than 5mV ripple
- Prototype expected to have 2.5 year lifespan
- Reference Electrode reading within 2mV
- Environmental Operating Temperature 15C to 35C
- Survive in high humidity
- Survive with exposure to H2S
Create a user friendly GUI and working Micro-controller
The bulk of the project will be to develop a working communication between the potentiostat and a GUI that will graph and log ARBcell data. The GUI must be able to log data for extended periods of time. The GUI will also need to take in data from the Arduino that is sampling for different channels and display all of those channels at once.
The Arduino is responsible for collecting the data from the three probes; working electrode, reference electrode and a set point voltage. This software will also manage the ADC and DAC, analog resolution, and clocking.
The Arduino is responsible for collecting the data from the three probes; working electrode, reference electrode and a set point voltage. This software will also manage the ADC and DAC, analog resolution, and clocking.
Improve potentiostat accuracy and reduce ripple
Improving upon the accuracy of the potentiostat is one of ARBsource's main priorities. This will be done through careful circuit analysis and testing, which will be done in a circuit modeling software as well as on a bread board with actual components.
Housing/Power supply
Another criteria ARBsource have given us is to create a housing for the potentiostat that can ensure the safety of the different instruments. This housing will include a light-weight, low noise power supply. Among the housing, the PCB will need to be protected against the extreme conditions it will be facing. Some sort of coating will need to be applied to the PCB to ensure that it is water resistant and corrosion resistant.
Last Updated 4/19/2014