When you say "can't strafe" does that mean it struggles to move very fast or literally no movement? If the latter, have you tried giving it a push to get it started? Is your acceleration in the forward/backward direction normal?
You might double check that your rollers spin freely. When I spin our (3 year old) AM mecanum wheel rollers, they spin for several seconds before friction stops them, or they are cleaned, adjusted or swapped.
Quote:
Originally Posted by JimmyNutrin
Thanks for the help on this.
By the way, how much would adding additional CIMS to each transmission help?
(I know that only 6 are allowed, for post-competition purposes)
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In general, the amount of power in your drivetrain is decided by the number of motors. More motors, more power. Power is torque x angular speed
Deciding on a gear ratio for your drivetrain is deciding how to distribute power between speed and torque. If you change the ratio, one goes up, and another goes down. You can't just pick any top speed you want, however. Your wheel translates torque to a linear force and pushes the floor, and Newton says the floor pushes back the same amount. This is the force that accelerates your robot. acceleration tells you how long it will take to get to your top speed. So, if you choose a gear ratio with a crazy high top speed, you won't have the acceleration to get to your top speed within a typical FRC distance. Or, you might not have enough torque to overcome the friction in your gearbox and wheel bearings to move at all...
soooooo, if you're still awake...
If you keep the gear ratio as is, but add an extra CIM to each gearbox, you are keeping the theoretical top speed the same but basically doubling your torque. It
would be legal to add an extra mini-CIM to each gearbox for this year's competition (assuming you haven't used them elsewhere)
OK, if you've made it this far, then one other thing to consider is the current draw of your motors at stall. Have you seen JVN's
calculator? This will show you speed and current based on your design choices.
Quote:
Originally Posted by JimmyNutrin
mechanum
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FYI - the spelling is mecanum.