# 2.57 cubes per second | VEX Tower Takeover

How does one have fast intakes that have the torque to bring in up to 10 cubes without using a red motor. I’m not sure how they are spinning that fast but compression is a big factor in play. I’m designing a bot that knocks driver skills out of the park.
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I would have to check my students’ design notebook, but let’s redo the math here:
18t sprocket would have little over ~2.5" outer diameter (including tank threads), say 8" circumference. If you use 200RPM cartridge, that makes 26.5"/s of linear movement (8*200/60), which is 4.8 tightly packed cubes per second in ideal conditions, way more than 2.57/s.

Now, would intake like that still lift the cubes into the tray? Let’s see:
We have ~1Nm per motor with 200RPM cartridge. At 1.25" arm (sprocket radius), that’s 31.5N. We have 2 such rollers, so in theory have about 60N of available force to push the cubes up the ramp. That’s over 6kg worth of cubes if vertical, and they are nowhere near vertical actually. With the ramp at 45deg and 10 cubes, we’d need about 20N to fight the gravity (10 * 0.28kg * sin(45deg) * g).
So far we were talking ideal conditions - no intake friction, no tray friction, no motor curve - once you load the motor (going backwards, those 20N would need about 0.3Nm per motor), the RPM would reduce. Slightly, since V5 is not a bare DC motor and its performance curve is shifted quite a bit (check your device info). But over all, we do have quite some headroom for the goal and it’s perfectly realistic as you see.

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