Activities
Subsystems Design
In this stage we completed the design of several major subsystems essential to operation of the PURE LiFe Generator such as:
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Created Comprehensive Test Plan
We developed a comprehensive test plan in order to ensure proper operation of critical components and systems of the PURE LiFe generator. We broke these tests up into related categories as listed below.
Testing Categories
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Updated Budget and Schedule
Milestones
- Completed the Client Status Report
- Completed Detailed Design and Subsystem Presentation
Tools
- Android Studio – For creating the Android application
- Arduino IDE – For writing code for the Arduino MEGA
- EAGLE – PCB design software used to design PCB to integrate LT3652 charge controller
Design Decisions
- We decided that the android application would only display graphical data for the current day's use, and extended data would only be stored on the PVOutput website.
- We decided to remove the GPS and forego providing location data.
Design Work
Arduino Code
Completed the Arduino code necessary for the PURE LiFe generator to properly monitor charging/discharging and battery state of charge, As well as sending this data over Bluetooth to the android app.
Android App
Completed the Android app design including all screens, navigation, graphing, Bluetooth connectivity, and PVOutput web connection.
Expansion Shield
Completed the Design and manufacture of the expansion shield necessary to interface our peripheral components such as current sensors, Bluetooth, and LCD to the Arduino Mega microcontroller.
Testing
During this period we have completed testing on our major subsystems of our design as listed below, with further testing of our full scale design to come.
Battery Testing |
Bluetooth Radio |
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Android Software |
Arduino Software |
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Various Real-Time Clock (RTC) Devices |
Inverter |
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Solar Charging System
- Solar Panel – Success
- Solar Charge Controller – Success
- Current Sensors – Success
Challenges
- The parts of our final design donated to us by Bioenno Power took longer than expected to arrive, so we completed the design of the software and expansion shield using our lead acid prototype.
- Communication between the arduino mega and LCD had several problems. The first was solved by connecting the LCD by serial communication instead of USB. There were also some errors with the LCD reading the data sent from the mega, this was fixed in software utilizing a static buffer instead of dynamic.
- Reading the unix time received from the real time clock on the mega and the mobile application provided some problems. This was fixed by setting the time zone to UTC on all devices.