Project Drivetrain Meeting Minutes 2022-11-28
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