The goal of this project is to design software for an EIS (Electro-chemical Impedance Spectroscopy) measurement setup. The hardware has the capability to do a MPPT (Maximum Power Point Tracker) measurement. The MPPT measurement will eventually be implemented, but this is not a requirement for this minor period. Why we want to measure the impedance of a plant source is, because by measuring the complex impedance, the company Plant-e (based in Wageningen) can determine how fertile/healthy the soil/plant is by comparing a new measurement to earlier impedance results. The MPPT measurement is used to determine the Maximum Power Point of the plant source; to optimize the power output for external electronics such as a booster IC.
Project decsription
The main goal of this project is to design embedded software for the LPCXpresso1549 microcontroller board from NXP. In the previous internship period, we have made a PCB for the hardware interface, this PCB has been placed on top of the MCU board in a waterproof case. The hardware interface will be controlled by the embedded software, which needs to be made during the minor. Without the embedded software the measuring setup is not able to work. The software will be used to make the calculations to determine the impedance. The software will autonomously control the entire measurement system. This means that the software will contain multiple control loops.
Project results
The result that has been acquired in this BeCreative Minor project is a fully autonomous EIS-measurement system. The system is able to receive input from the user to conduct EIS measurements with user customizable frequency ranges. The software of the system has 3 different modes which each have their own console program, to make it more user friendly. The 3 different console programs each have their own function, which are the following: programming customizable measurement parameters, extracting the measurement data, and calibrating the system.
All main requirements of the EIS-measurement software were successfully implemented and tested:
- Measurement frequency range of 1kHz down to 1mHz
- Low operating power; the code will ensure that the microcontroller will go into sleep mode whenever possible to save power
- Automatic offset control
- User-friendly interface
Video
Acknowledgement
We would like to thank NXP Semiconductors B.V. in Eindhoven and Plant-e in Wageningen for giving the opportunity to Fontys students to work on this challenging project, and for their support during the project.