Black Widow (altimeter bay redesign)

Black Widow has not flown since November 2016. It’s a good rocket but has some usability and recovery problems. The goal of this project is to refit it with new electronics and solve as many known problems as possible, making this back into a workhorse high-performance rocket. I have five flights’ worth of data and video to review and see where improvements can be made. This page is just a copy of my own project notes.

TODOs as of 4/16/2023:

• Select and order 2-conductor locking plugs for battery connection [DONE, ordered 2- and 3-pin JST SM connectors from Adafruit]
• Modify sled design for correct BlueRaven footprint [DONE]
• Print new sled [printing now]
• Assemble & wire new sled
• Test BlueRaven app (by itself and with AltOS)
• Bench test
• Select new parachutes
• Check rivet holes and re-drill if needed
• Ground test
• Design new nose sled for TeleGPS
• Drill nose for pin switch (maybe)
• Print nose sled
• Test old Mobius camera and make sure it still works OK
• Clean everything
• Touch up paint (maybe)
• Paint alignment keys where needed
• Design and print new "ground station" bits (see below)

Project notes:

• Entirely new 3D-printed sled [designed, first iteration printed]
  • New BlueRaven altimeter
    • FIX NEEDED: Blue Raven mounting holes do not have the same spacing as the old Raven; need to fix them
  • 7.4V LiPo battery
    • Keep its charging plug accessible
    • Should have some way to keep the power connection locked, since it's not a locking plug [decided to replace the battery plug with a locking connector that can be accessed with the coupler over the sled, so the pin can be put in the pin switch before connecting the battery]
  • Pull-pin switch instead of magnetic switch
  • Think about how to make charge canister hookups as easy as possible [decided to keep existing setup with terminal blocks on the inside of the bulkheads]
  • Wiring should be hidden or managed by the sled as much as possible [for now I think I'm just keeping wiring neat with zip ties]
• TeleGPS
  • Design and print a new sled
  • Could it use a pull-pin switch also?
• Camera
  • Is it possible to remove the old shroud and replace it with a new one for the new camera? [In short, no; if we need to switch to the new camera, we'd have to replace the entire upper airframe tube.]
  • Otherwise, is it possible to add the new camera horizontally in the center bay? [No.]
• Recovery
  • Possibly replace drogue chute
    • Re-watch old videos and see if there’s a solution to drogue problems (spinning, falling nose-down)
    • Have multiple notes about the Spheracutes drogue pulling the upper and lower airframes together after apogee, and either colliding or nearly colliding
  • Possibly replace main chute
    • Have had multiple occurrences of the primary charge not getting the main out
• Performance
  • Look for any places weight can be reduced
  • Are the Rocketry Warehouse tubes that much heavier than Wildman tubes? Compare with [Home Alone]
• Physical assembly
  • Make sure everything has clear alignment keys (stripes on outside)
  • Check coupler fitting on cold & hot days
  • Check fit & usability of plastic rivets
• Telemetry
  • Determine whether I can run the BlueRaven and Altus Metrum apps together
  • Add a phone holder to the Yagi antenna
  • Add “feet” to the ends of two reflectors on one side of the Yagi so it can be set down on the ground or on a tabletop (with the reflectors vertical and the camera and phone right way up)
• Sim & test fit DMS L1000 (currently sims about 10k/750mph)
• Update the checklist