I designed 5" ball turret shooter

I have created a 5" ball shooter

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Looks great, but I really worry about putting the flywheel directly on the bell of the Neo Vortex. The motor can is just cantilevered over the stator coils. It’s not meant to take a lot of radial loads, and an imbalance or a heavy game piece could cause the magnets to crash against the stator.

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Neat

What’s the strategy for fabricating/retaining these?

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You also have some interferences in the “Azimuth” plate to resolve. Should be relatively easy by moving fasteners around or using countersunk flat head screws:

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seems i have forgotten to add mounting plates for them

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Some quick, direct, hopefully constructive feedback :slight_smile:

I like the way you have the flywheel axle plate constructed from sheet metal. Big fan of that technique. You need to be careful of that bend because it is really really hard to get your axel bearing holes to line up correctly. And I mean really hard without a CNC brake or trying over a dozen times on a manual brake (you may need to 3dprint an alignment jig for the manual brake).

Looking at the hood position control:

By controlling the angle near the flywheel you effectively multiply all the forces going into the gearbox from shooting, collision, etc. there is nothing wrong with doing it this way, you just need to be careful. A lot of teams counteract this by running this control in the green area with a small pinion gear and large bullgear, reducing the angular error from backlash and reducing loading.

I would increase gear tooth size/pitch diameter to as large as you are comfortable with in the red area to make things more robust. I would also find some way to sync the left and right hood plates where they are driven so there is no weird racking/twist. This will also reduce loading on those teeth.

I would also look into taking up the backlash with a low strength gas springs (2-5 lbs?) In the green area. Gas springs have the added benefit of a shock absorber, so you may not be able to move things super fast, but your hood shouldn’t move much from rapid loading.

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This is a goofy idea, but could it help to remove the coaxial hex shaft and shock mount the motor with TPU spacers?

It would reduce crush consistency but would maybe alleviate the rotor deflection.

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The hex shaft is solid all the way through, the answer imo here is to not drive anything off of the bell, rather have the power path enter the hex shaft and re-enter the flywheel from the hex. There is good reason to take advantage of the through-bore capabilities for packaging so long as all the motor curves fall in the right ballpark and it is all 1:1ish.

Personally I think I would size up the flywheel slightly to protect the motor bell against accidental knocks. I don’t think there is a lot to be gained from having the axle float around for launching a spherical object. You are going to want to keep compliance/flex in the system as constant as possible throughout the season. If TPU inserts on the axle are the magic juice for your solution then go for it if course. I would be careful with dynamic axel shifts though because it is hard to evaluate when prototyping. Someone more familiar with TPU material science may be better suited to answer questions around wear, degrading, and print consistency

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Manufacturing concerns aside, I would also question the stiffness of the entire shooter. Shooter stiffness is one of the most important factors that affect its accuracy (second only to correct compression) and this shooter doesn’t look like it would handle the recoil of shots pretty well which could lead to major inaccuracy, especially when combined with the backlash from the hood gears.

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for manufacturing the “sheet metal” parts we actually have a bunch of 2x4 aluminum that we can cut them out of so we don’t have to bend them cause we dont have a brake. (for some of the bigger parts we have a sponsor that can bend them if we really need it)

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So the bracket for the flywheel axle piece, that the 5"ball passes thru, is hypothetically made of 2 pieces? Or is that a sponsor bend?

why would it need to be 2 pieces? or what do you mean?

if you mean the main big piece and the side bearing pieces they are seperate

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@Skyehawk @Alex_Y @gerthworm @nuclearnerd @Skiddy4795

I have taken some of your advice into consideration and moved the hood actuation to the back, along with other minor tweaks.

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This looks like an excellent second iteration.
Looking forward to going thru than CAD.

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What is the expected nominal diameter of the ball? The rear frame and Colson wheel has little compression, so you’d need the ball itself to be compressible (or inflatable) to get enough traction for a consistent shot, or what I call the “squish factor”. Most inflatable balls in FIRST also have variable diameter due to their acceptable variance in pressure. Do you have a way in this design to move the flywheel in or out to account for additional compression?

Looks like the padding on the hood could be adjusted, which is changing far fewer variables at once than moving the flywheel axle (resulting in variable compression)

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The padding on the contact surface is meant to be adjustable.

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