Communication System Subsystem Build & Test
Table of Contents
Vision for Communication System Subsystem Level Build & Test Phase
The goal for this phase is to fully populate and test the communication system this phase. This includes:
- I2C and the sensors that communicate via I2C
- SPI (Just the ability to TX)
- 2m communication
Also the APRS will be tested as soon as it arrives.
Results of this Phase for the Communication System
The PCBs came in early on in this phase and the whole team immediately started to populate the boards in the RIT SMT lab. After a quick debug of a few parts being either wrong or orientated wrong, the board was powered on correctly and testing began.
The APRS and Baofeng UV-5RA radio arrived early on in the phase also. All of the components of the communication system are shown below.
Test Results Summary
Many aspects of the Comm Board were tested in the past few weeks. Overall, the results were positive.
Test Plan Results For Communication BoardThe steps that will be used to test out the communication board are as follows:
Board Power TestThe three buck converters that step the 12V input to 5V, 5V and 7.4V respectively were tested for various permanence characteristics. The reults are in the spreadsheet below.
Board Signals Test
Next the signals in the communication board that come from the Raspberry Pi were tested. This was facilitated by test files that were made on the Raspberry pi.
Guide to setup the PI to SSH for Windows 10A guide on how to setup the Raspberry Pi is linked below
2m Communication TestThe test that checks the functionality of the 2m Communication system hardware is shown below.
Other Communication System Tests
The APRS was set up to transmit the W2RIT callsign once a minute and to have a callsign ID of 11(for a High Altitude Balloon). The test document for the APRS is shown below.
The APRS successfully got GPS lock and transmitted to the 2m repeater that is on RIT from the METEOR lab and from one of the team members' house.
Future work for the APRS will involve debugging why sometimes the Arduino Leonardo chip on the APRS gets into an error state upon startup.
Master Test Results Page
The document containing all of the test plans and the results of the tests performed thus far are located here: Test Plans
Risk and Problem Tracking
Problems that were overcome was that the communication board did not power up correctly and the 7.4V output was not correct.
Problems that still exist are the APRS not booting correctly some of the time. The document will the documentation of these problems as well as the problems of the entire project are shown below.
A link to the Problem Tracking document can be found here: Problem Tracking
At this point, the main risk of the communication system is that the 2m communication may not be rugged enough if the software is not improved upon from the state it was in 2 years ago.
An updated Risk Document can be found here: Risk Document
Functional Demo Materials
The aspects of the communication system that are to be demonstrated at the end of this phase are listed below.
- Demonstrate working GPIO for the radio and Buck converter disables.
- Demonstrate working I2C communication with the GPS, pressure sensor, and temperature sensor.
- Demonstrate working SPI communication.
- Demonstrate working APRS.
Plans for next phase
- Get board-to-board communication working with the Comm board to the DAQC and the Comm board to the CBOB.
- Get the 2m communication working and have the ability to respond to commands.
- Verify the GRSS enable and Nichrome wire cutdown method.