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Unread 24-03-2014, 17:11
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JTN JTN is offline
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AKA: John Taylor Novak
FRC #0016 (Bomb Squad)
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Re: Baxter Bomb Squad 2014 ~ Nighthawk

Quote:
Originally Posted by avanboekel View Post
Do you mind providing a picture/ explanation of the thrust bearing system?
The only thrust bearing system is machined in the plate that houses the integral part of the swerve module, so that is what I will assume you are asking for. The thrust bearing is machined into two opposing plates and smashed together by the screws that also happen to hold it together. Here is a picture to show the inside of what it looks like:



(I circled the two channels for the ball bearings. Also, that sprocket is NOT floating, it is being held up by a piece of delrin that cannot be seen in the part section view.)
The two black plates sandwich the BBs between them and act as the thrust bearing.

I felt the need to add pictures of the plates themselves. The smaller round one is hidden just above the blue 3D printed part that is an unmentioned experiment for this year.





Quote:
Originally Posted by tafipapi View Post
The maximum speed with this gearing configuration should be about 14 fps right? Is that Nighthawks's speed?
The maximum calculated speed is close to 14 fps, but the real speed due to outside forces such as friction is closer to 12-13 fps.

Quote:
Originally Posted by wet_colored_arc View Post
Your team has been kind enough to share the design of your swerve and describe how it works when I have visited in your pits. When thinking about it, I have always been unsure about a manufacturing aspects of your design.

How do you get alignment of the "tower" to the wheel support structure? How do you assure center to center alignment? and then how do you assure perpendicularity of the tower to its mating piece at the bottom. Is it just a matter of being very careful with conventional tooling, do you somehow machine it as one assembly or is there some other hidden trick you can reveal?

I would think this would be particularly important, doubly so because of your integral, custom bearing assembly.
The method of attaching the "tower" as named above to the plate itself is actually much simpler than you might think. The thrust bearing actually is what holds the module and sandwiches the mounting plate between it and a couple of machined pieces of delrin on top. The piece is just a small aluminum block machined into an angled bracket that is also what compresses the thrust bearing and holds the entire assembly together. All of these parts are machined with CNC mills (some manual mill work is added but nothing major) to ensure all the parts will fit together very tightly and accurately, providing the perfect 90 degree angle between the module and the plate. The image below has the small plates (only one is visible) highlighted in red and the 3" tube highlighted in green for ease of visibility. More images of the overall assembly can be shown if needed to get a full perspective but until then I don't feel the need to clog up others' bandwidth too much with all these pictures!



If you have any other questions just let me know!

-John Taylor Novak
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Last edited by JTN : 24-03-2014 at 17:25. Reason: Picture was too big and I didn't like it.
 


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