Intake wheel motors

[Jared Russell]

Originally Posted by Ginger Power

Another tip for intake wheels when it comes to selecting the right gear ratio and motors: Your "intake velocity" aka the linear speed of your intake wheels should be greater than the max speed of your drivetrain. This makes it easier for you to intake a game piece while driving at it full speed.

As a huge fan of fast intakes on a team with a reputation for building fast intakes...

I've heard this rule of thumb parroted around a lot, but (in my experience) this can lead to teams building drastically undergeared intakes that stall at the first sign of trouble.

There is more that goes into a roller intake than speed, and high speed can bring with it some drawbacks. For most game objects that FIRST has given us, an effective intake requires carefully crafted geometry, materials selection, and deformation characteristics to work well. You may find that your mechanism is loaded in such a way during intaking that in order to prevent a stall when loaded AND run at a greater tip velocity than your maximum drive speed when unloaded would require a ludicrous amount of power. Or, you may find that a high tip velocity breaks static friction between the roller and game object when the robot isn't at full speed (i.e. most of the time).

It's really more of an impedance matching problem than a raw speed maximization problem (though adding more POWER to the equation usually helps). A lot of these tradeoffs are non-obvious and difficult to estimate from first principles, but can be the difference between a ridiculously effective and totally ineffective intake. Every team guesses wrong on total intake power and speed/torque from time to time. Unless you have the ability to quickly remake a custom transmission in-house, you really can't beat the VersaPlanetary for being able to quickly change your mind and adjust any or all of the power parameters of your mechanism.