How to code a motor without a cartridge in pros

Programming Support
#1

My team and I are trying to code a motor without a cartridge in pros, and I wanted to know if we just don’t declare a gearset or if we do gearset invalid. Is there something else we should be doing?

#2

1: Motors are meant to be run with cartridges; if you can handle 3600 RPM, go right ahead, but it might be better to gear up a 600rpm cartridge.
2: You can define a normal gear cartridge ratio, but some functions like motor_move_velocity might not work as expected. Failing to declare a gearset might throw errors when calling functions that use it to calculate values.

#3

Couldn’t you just treat it like a regular flywheel, and declare it a blue cartridge? That’s what we did when we had a flywheel.

It would work exactly the same, the only difference being the output rpm would just be incorrect. I wouldn’t recommend using this for a flywheel tho, I would do some sort of controller, like sylib or pid.

Actually, a 1:1 custom cart if done correctly will be better than any external gear ratio because of two reasons:

  1. Less friction -better spin up better keeping speed
  2. The ability to make it more compact

Although that being said, if done incorrectly it could potentially break the motor for future use.

That being said, doesn’t mean they can’t run without them ;))

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#4

So I’m a little confused. Are we able to just leave it like this:
pros::Motor Shooter1_initializer(SHOOTER1_PORT, pros::E_MOTOR_GEARSET_06, false, pros::E_MOTOR_ENCODER_DEGREES);

Or do we have to replace the Motor Gearset with something else?

#5

Nope, just create the object as pros::Motor [MotorName]([PortNumber]). No need to specify a gearset. This is assuming you’re using c++.

#6

by no cartridge do you mean the default cartridge or that you literally took the cartridge out.

#7

There is no “default cartridge.” So they mean just the motor with no cartridge.

#8

I thought motors came with a green cartridge inside of them when first bought but maybe that’s changed?

#9

That would correct, they do come with green (200 RPM) cartridges. However, what the person who created the thread is asking about is completely removing the default cartridges and making a custom 3600 RPM cartridge - there are many ways to do this and it legal per a Q&A. But it seems like this question has already been answered by RealCow. pros::Motor [MotorName]([PortNumber]); would be correct.

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#10

I mean technically… yes. But they literally are running it with no cartridge.

#11

While the VEX website calls the green 18:1 cartridges standard, as seen here, for purposes of an actual robot, the application determines which cartridge you’d use. And yes, they do still ship with the green cartridges pre-installed as of today.

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