Project Drivetrain Meeting Minutes 2022-11-28

Owned by Thomas Valer
Last updated: Nov 29, 2022
4 min read

Battery Action Items from Previous Meeting

  • U bolts need extra design considerations to prevent sliding and rattling

  • Initial intention is to use velcro straps to secure the battery

  • Cushioning in metal part would be great

  • Separate locating features from clamping features

  • Next Steps

    • check possibility of using a plate and standoffs

    • Nail down exactly what connection method you want to connect the ubolts to the battery

      • sheet metal vs plate etc

    • Add some locating feature to constrain the position of the battery

    • figure out how to connect battery to plate or sheet metal part (straps, velcro, etc)

    • wrap up cad after that

    • reducing vibrations

Revision with plate

  • get ebox height for josh

  • rough weight check

 

Ebox Prev Meeting Action Items

  • Shelf design will likely not work due to wiring

 

Next steps

  • Priority access list

  • Wiring to/from components

  • Revisit layout & look at CAD for integration ideas

Ebox Past Week Progress

  • Talked with Farris & created priority access list

  • Created initial design idea for ebox that allows easy access to most components, low CG, adequate cooling

    • Open to feedback/suggestions

  • Contacted protocase & inquired about integrating polycarbonate into design

    • Thinking it will make it lighter and is non conductive

    • They said they can but there are limitations and they need to see the design

 

 

Comms/Gimbal mount

What Have I done?

  • Had a meeting with Austin and Billy about antenna interference and importance of placing gimbal on the same plane as the antennas.

    • Not very important, recommended if we do put on same plane to make frame of gimbal with plastic to minimize interference.

  • Created two different very rough prototypes:

    • 1: Different level gimbal and antennae

      • Pros:

        • Antennae

        • Antennae in open air, best case for interference

    • 2: Gimbal and antennae all on same plane (not my favourite for reasons mentioned later

      • Pros:

        • Vision

        • 360 FOV

        • Over arm most of the time, better vision with arm connected

      • Cons:

        • top heavy

        • Will need to manufacture camera frame with some plastic because of interference

 

Problems

  • In original prototype 2 design, made vertical scaffolding distance wrong (260mm instead of 280mm) and now an antenna is placed on top of a vertical square tube. This is a problem because there is no way to secure the coaxial cable to the antenna and properly tighten it without seriously modifying current assembly.

  •  

  • Arm will hit gimbal if it is mounted in front

  • Camera in current situation will only allow for around 180-190degrees horizontal FOV due to servo and frame obstruction with scaffolding.

  • Space below gimbal is 7.52 in / 191mm total

 

Suggestions

  • Change limit switch on A3 since it only accounts for the arm hitting the chassis/drivetrain. Current configuration will most likely hit e-box and gimbal.

  •  

  • Suggest not letting the arm pass this angle as to miss the farthest extent of the gimbal (45 degrees back). Distance here is 8.3 in (more than 8.26 in). Can alos try and move camera off to the side a little so that the arm doesn’t have to be in a weird position (sideways or outstretched forward) every time we want to see something with the camera.

  •  

  • I believe 180-190 degrees FOV is not bad at the moment. Can always just turn the rover. It would be great to get more.

    • Options:

    • mounting closer to the front (less arm maneuverablility)

    • mounting on the same plane as the antennae (not a big deal according to Billy).

  • Can always either move to a plate design for the antennae such that they can be mounted on the back.

  • Looks a bit odd but this could also help balance the moment on the scaffolding.

 

Questions

  • How to add prototype stand to mainassy without disrupting GrabCAD?

  • Is the height clearance okay with Josh? Possibly consider mounting gimbal on top of E-box again.

  • Thoughts?

 

Action Items

  • Check if moment created by gimbal is a problem with FEA

 

Blockers

  • Very busy weeks ahead due to school