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  • Structures

    • Requirements

      • Distinguish between should and shall with DTEG reqs

      • Consistency in dimensions (diameter, radius)

      • Use testing over analysis for FoS

    • OpenRocket

      • 10 mph wind case

      • Loki Research motor

      • Both satisfy rod speed req using base mass

    • Motor Selection

      • TWR calculated with ~28 kg mass

      • CTI issues (can be elaborated on later)

      • Is the Loki motor in stock? (need to check on that)

      • Need to do a more in-depth price comparison for jumping to N-class

      • Have we considered the M6000? (large overshoot)

      • Motor unreliability as we jump classes? (likely a non-issue, consult tech reports to confirm)

      • Loki motor burns blue, pretty cool

      • Prioritize off-rod velocity

      • Test parts to higher stresses if concerned with a more powerful motor

    • Nose Cone

      • Is the strength difference between CF and FG a valid concern?

      • What is the basis for saying CF is easier to remove from a mold than FG?

      • Are we considering different shapes at this stage?

        • Not considering other than a tangent ogive

        • Possibly look at Von Karman

      • Don’t worry about a tip for Mach reasons if under Mach 1

    • Body Tubes

      • Layup has less surface finish work than winding (except for seam line)

      • Layup strength comparison is dependent on the direction of fibers in purchased cloth

      • For winding where would we apply graphite powder?

      • Consider using the paint booth for heated cure cycle (look at temperatures needed and temperatures that can be achieved)

      • Winding pattern (current 60/30) though to change because of manufacturing process

      • Find out weight difference between layup and winding

      • Consider mechanical improvements to the X-Winder (in progress already)

      • FG frays far more during winding

      • Consider sourcing better FG tow

      • Prepreg FG tow?

      • How does cost per weight translate to cost per length unit of tube?

    • Bulkheads

      • Spar thicknesses vary a lot

      • Uniform spar thicknesses for testing and adding fillets to the thin membrane

      • Decrease overall bulkhead thickness (.5” to .375” or .25”)

      • Consider mounting space when looking at spar design

      • Why does the four-spar bulkhead maintain equivalent strength as a solid bulkhead with less mass?

        • Section moment considerations

    • Rail Buttons

      • SRAD

        • Why not machine plastic rail guides?

        • Aluminum rail button testing on L1s?

        • Plastic is actually easier to machine

        • Are these rail buttons better than COTS?

        • Not many teams use SRAD

        • Combo Al/Delrin rail buttons

      • COTS

    • Boat Tail

      • 3D Printing

        • Consider heat deflection temperature, not melting temperature

        • Glass Transition temp for PETG is around 80 degrees Celcius (per Deeb)

        • Consider simply using PETG again if using same or lower-thrust motor

          • Careful is going to Loki or higher

        • Consider layer height for printing

        • Worth testing layer height strength properties

      • Composite Layup

        • Is the compressive strength worth it here if using a fibrous material?

    • Fins

      • Numerical optimization for fins

      • Concern about lack of fin tabs if using tip-to-tip layup

    • Thrust Plate and Motor Retainer

      • The screw size restriction was due to the size of retainer

      • Think about screw on and one “locking” screw through both pieces

      • Slide 45: NO

    • Blockers

  • Avionics

    • Requirements

      • Minimize in-field assembly time by doing more before arriving at the VLA

    • Wiring Diagram

      • Add switches to GPS

      • Careful about where wires plug into

    • Backplane

    • Connectors

      • Move placement of connectors

      • Consider alternatives for bulkhead wire pass-throughs

    • Flight Computers

      • Why only RRC?

        • Because

    • Trackers

      • Featherweight ground station data can be sent to our ground station

      • Featherweight is more reliable

      • Cost of featherweight is comparable

      • Working ground station is good

      • Big Red Bee size is far larger

      • HORUS will not get drowned out

    • Live Video Transmission

      • HDMI connections can be somewhat unstable

        • Perhaps mitigate by using a small 3D print bracket

      • Drone cameras will likely be rated for higher G loads than the rocket will experience

      • Range ratings are likely unreliable and should be tested

      • RF transparent materials can still affect the signals

      • Live video challenge requires 1080p 30 FPS

      • Bad video is still worth something

      • Interference concerns with transmitting on crowded bands

        • Video transmitters can shift frequencies

        • Need to see if MCC approves that

      • Need to consider the drain timeline

      • Consider sending a turn-on signal to start the live video

        • It could also use boost detection

      • Really need to deep dive into how we can safely remotely turn it on without missing boost

    • Heat Management

      • EMI generation is likely a non-issue

      • Thermally conductive plastics

      • Turning on the runcams close to flight could negate the need for an airflow solution

      • External heat sink can cause more damage upon recovery

      • Test a large amount for fan system

      • Figure out activation issue before heat management to understand how much heat management is truly needed

      • EMI could also throw off magnetometers on non-flight critical components

    • Battery Chemistry

      • No individual lithium-ion cells

      • Look at batteries with leads rather than contacts

    • Engineering Cameras

      • LED is to help ease the exposure shock from brightness in NM

      • Come up with the number and location of modules

      • What view are we looking at for live video?

      • Need to have a large camera discussion with multiple subteams

  • Avionics Bay

    • Removeable Bulkhead

      • Inset Edge Circle contains the load and makes the connection weaker

      • Clover should not have a manufacturability issue

      • Add in a flat on the clover for keying

      • Clover design can only be epoxied on one side for fillets and the application must be careful to not impact the keying geometry

      • Consider how deep in the tube the clover is

      • Consider what tools can fit in to actually screw in the key

    • Material Selection for Skeleton

      • Waterjet isn’t as much of an issue this year

      • Check Metals Depot for Aluminum

    • Component Mounting

      • Label things

      • Removable top if implementing fixed sleds

    • General Improvements

  • Recovery

    • Requirements

      • Take care to follow the main altitude deployment DTEG

      • Give time for the main to inflate to meet the speed req

      • Consider how payload’s recovery system deploys

    • Streamer

      • Mitigate the length of the harness to reduce tangle risk

        • Dual Bay helps with this

      • Understand why we use a streamer instead of a chute for drogue

      • Consider Pilot Chutes

    • Main Chute

      • Find out and compare chutes based on descent rates

      • Decide on the correct size for the mass of our rocket (likely larger this year)

      • Vented chutes open far slower than non-vented

      • Put more thought into other factors surrounding descent rate decision

      • Consider Pilot Chutes

    • Links

      • May need to buy more quick links

      • Visual indicators for quick link tightness

    • Shock Cord

      • Maybe look into lower-rated shock cord

        • ESRA might want us to use 5000 lb for some reason

      • Ratchet Straps?

      • Cord Length needs to be figured out

      • Watch for corrosive BP protection

      • Consider how to secure the line protector

        • Sewing

      • Compare cut resistance of shock protector

      • Could attach COTS protection with heat shrink on either end

      • Reference OMEN Tech Report for Separation Shock Calculator

    • Foxhunt

      • Figure out where to place foxhunt beacons in the rocket

      • Look into other foxhunt beacon options

      • RS41 can possibly act as foxhunt beacon in AV bay

    • Test

      • HAB streamer tests?

    • Blockers

      • Consider Wildman Rocketry as a recovery component supplier

  • Payload

    • Requirements

      • Make sure payload can transmit without extended member

      • Recovery has not imposed any interface requirements

      • Sabot keying requirement

    • Extendable Antenna

      • Dust considerations hindering mechanical systems

      • Sheet metal manufacturing should be somewhat simple

      • Fishing line as an extendable string

      • Consider using the extension as a 2m antenna

    • Self-Righting Mechanism

      • Figure out what to do if it lands on the top or bottom

      • Round bottom and modify sabot

      • Is it worth the cost of a COTS emergency HAM inflatable antenna?

        • Too large of a package for the member

    • Frame Ideas

      • The Back Plate has more strength concerns due to larger moments

      • Stilt City - thanks yev

      • Offset parachute introduces more concentrated stresses and increases the possibility of shearing shroud lines due to contact with edges of the payload

    • Parachute Antenna

      • Mini Chutes

      • Crazy antennas are mitigated simply by another tracker

      • Extra parachute is a massive tangle risk

    • Battery Options

      • Use packages with leads not individual cells

      • Flat pack battery options

    • Cameras

      • Second lens on cam #2 has both analog and digital lenses

      • Also considering the same higher-end runcams as Avionics

    • Sabot

      • Change where the shock cord pass through is located

        • Does not fit into tube tightly as is

      • If implementing the band idea run it through both sides

    • SRAD PCB

      • Scope creep concerns

      • Most of this can be reused in terms of board design from previous boards

      • Figure out if the PCB provides power to servos as well as control

    • GPS Tracking

  • Finished