Meeting Notes - Avionics - 2023-07-16

Date

Attendees

Goals

  • Talk about backplane errors and get it tasked out
  • Talk about cool new backplane features we can add


Broader Document: https://docs.google.com/document/d/1JiIO9wGDzHulcxufFffeiabLy4sfvlwOgKgPBwByLmg/edit

Design Improvements

  • More documentation and calculations
  • Software needs to say what they want for hardware

Sensor Module - Louis Fleisher (RIT Student) 

  • MS5607 takes the complement of the line for address, buried in datasheet, causes address conflict with the BMP388. 
  • A second UART is available for use. Print debugging through SWD is more annoying. 
    • Investigate turning SWD into a UART
  • Conflicting GPIO interrupt pins between LSM and LIS
  • E-fuse EN/UVLO pin pulled down too far to enable the chip at 1.2V for off-nominal, board does not power on. Just change a resistor and redo calculations.
  • Do we want to get rid of interrupts?
  • Set priorities for sensors

Improvements

  • Don't know how much more it needs/can do. Already crowded
  • Increase efficiency by redoing layout.
  • SHTC3 not good in software. Already have other temp sensors. More ambient reading than TMP117. Also does humidity (not needed)
    • Need to verify theres a difference with ambient reading. Check accuracy compared to other sensors
    • Don't see need for it to be replaced, but could shop around for interesting sensors. Covered bases with what could be measured in ICs. 
    • A lot of things we can throw on that are nice to have. Think of other interesting sensors we can do.
  • Noticed that BMP581 is available and can replace BMP388. Low power consumption, higher accuracy and similar pricing
  • Look into MS5611 as a replacement to MS5607
  • Investigate using a 9DoF IMU instead of a 6DoF

Radio Module

  • UART Debug line labels are mismatched
  • Ethernet LEDs not attached to anything
    • Copy sensor module Wiznet LED implementation
  • Need to know it works (software). Needs to function our specifications. Does it work and is it useful in its capability?
  • Little improvement for now

Power Module - James May (RIT Student) 

  • Copy sensor module Wiznet LED implementation
  • Power inductors very difficult to solder by hand, recommend fab house assemble them on future revisions
  • 5V and 3V3 rail voltage drops proportionally with load, up to a ~0.4V drop at 3A this was due to faulty load tester readings, module functions as expected
  • Wiznet LEDs disabled only by desoldering
  • Jim suggests targeting above nominal voltage for 200 mV response to voltage drop?
  • Bulk capacitors causing shorting issues, root cause still unclear

Autopilot Module - Ben Hyman (RIT Student) 

  • Probably nothing. Not enough known yet

Jim

  • Give us schematics he made
  • Fix the dev module orientation connector. Wrong way.

Software 

  • GitHub Issues page with list of tasks
  • Startup cost is higher for doing Arduino 
    • Having them move from Arduino can be a lot when switching 
  • Should new people immediately use launch-core?
  • Arduino support needs to be implemented so we can use it PROMPT. Could also be used on SCRAP for a variety of payload missions - Chloe Clark (RIT Student) 
  • RFM needs to be implemented so we can check if the hardware design is good
  • Ground receiver software
  • I could write a book about this

Overall

  • Need keying geometry because connecting stuff properly is hard

Action items

  •