https://youtu.be/OeSR3pGzmSI 1577 Steampunk is always impressive. Check out their new intake, modifications to auto and overall well built structure of this Charged Up robot on Behind the Bumpers.
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Thank you for the video Tyler, we always love having you in our pit.
I’d like to mention that the intake is a mix of a few inspirations we took alongside team 95’s - we also looked at team 6328’s open alliance thread and team 2230 from Israel in our first event.
For any questions about the team and the robot feel free to ask, the students and I will be available to answer
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Great robot this year. We were watching you guys close at your week 1 event. Your robot seems very simple and was very fast. I had our drivers watching your matches while we were traveling to our week 1 event. Your driver is very good and did a great job spinning out of defense.
From the FUN video can you give some pictures of the back to back bearings on your intake? I am always looking for different bearing options for intakes.
I didn’t find any good pictures on my phone, but i’ll try to explain the best i can from the video itself.
Basically we have 2 external bearings going through the plates with the shoulder facing outwards, like most teams do. The other bearings are mounted inside the intake with the shoulder facing the plate itself like in this image:
The plate is blue, and bearings are red. the plate is 5mm thick and the bearing OD is 1/4" long, so the plate can move about 1.35mm between the bearings shoulders.
The internal ring of the bearing is of course free to spin, and only the shoulder/bearing OD is touching the plate at any time.
This results in a very robust spinning axle, while not affecting the flexibility of the polycarb and not requiring any holes to clamp the bearing to the plate (only the shaft is tapped, and closed at the ends with end screws).
Hope this was clear, if not we’ll try again after we get our robot in ~2 months 
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@Guy
I know this is a bit late but what type of control do you use for your arm extension and pivot?
Is it just PID, or something more complicated like motion profiling with feedforwards?
What was the point of the cf-spring? I thought it might have been to remove the need for a gravity feedforward for extension, but the force of gravity along the plane changes depending on the angle so it can’t always counteract it, so I don’t think it’s that…
So the arm + telescope were controlled with a motion magic & gravity feedforward. On top of that, we orchestrated them with our own planning algorithm to move them together without hitting anything in the robot or the grid (we kept it simple and didn’t generate a full motion profile, but only added in worst case 2 safe waypoints before the final target).
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We geared the extension of the arm quite fast, so the spring mostly helps when the arm is vertical and pulling a cone as it had a harder time with that. so for horizontal mode the spring “fights” the extension of the arm, but for retraction and picking up game pieces it helped speed up things.
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@Guy Didn’t that mess with the PID in some way for the extension?
What was the gear ratio you guys were running on the extension motor?
Not really, I don’t remember having too many issues with it. maybe we took the arm angle into consideration when extending/retracting, @Lidor51 can elaborate further on it.
I think the ratio was 1:3 if I recall correctly.
When the telescope was fully extended, it did require to apply additional force in order to counter act the spring.
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