Optimizing Intake Rollers

Now that the meta designs are relatively evident, I see both advanced trays and tray db4s remaining prevalent for quite some time. Both of these designs use intake rollers to pull cubes onto a tray. This begs the question, what kind of intake roller is best? This post is a general purpose question to see what’s working well for the community.

Intake rollers need to provide enough compression to intake 11 cubes (in extreme instances) while also allowing stack deploys to remain unaffected. What is the ideal length of flap, size/ratio of sprocket, and frequency of flap (links between flaps) to achieve this most efficiently?


I think the shortest flaps are best for this because they are more rigid and able to push cubes upwards. That is, the energy from the intake is more efficiently transferred with a more rigid design. This is why FRC teams use solid wheels for intake and though this isn’t FRC, you can learn a lot about intakes from those robots.

I think one of the best robots from previous years is Fred VII (https://www.youtube.com/watch?v=Ox8MIW7khI8) and the intake on this bot uses double flaps. That means more energy is transferred to the object it is intaking because the flaps are less malleable and less energy is lost in the deformation of flaps. I think this is key.


According to videos of final matches in China, it seems like 18T sprockets powered by 200rpm motors will be able to pick up 11 cubes. From my own experience, 24T sprockets intake cubes faster, but they can only pick up about 8 cubes. I’m not sure about the relationship between flap length and intake speed/compression.


what is a tray dr4b?

Its a tray bot on a DR4B. This is a good example of it:

I like straight line 18t intake. It’s fast and the straight line seems to help with straightening the cube.

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