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Unread 16-09-2009, 08:45
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JesseK JesseK is offline
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Re: [FTC]: FVC (Vex) VS. FTC (Tetrix)

So generally speaking, teams who have 4 VEX motors on their drive train and a 25-lb VEX robot will typically not move as fast as an FTC robot that weighs 25lbs with 2 motors on the drive train (#'s below). Yes, there are tradeoffs. It will be interesting to see where teams decide to fit all of the electronics for 8 Tetrix motors, 3 lego motors, 4 Servos, and a bajillion sensors...

FTC's structural components leave ALOT ... wait ... ALOT to be desired. They're difficult to work with to do tricky things, and I think part of the challenge for this year will be getting those structural components to become something that can move the balls into the goals. Alas, to FTC's aid, the GDC has allowed many extra materials.

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FTC motors output just over 1.5 N*m of torque at 150 RPM whereas the VEX motors output 0.73 N*m at 100 RPM. (is that math right? I don't remember a 0.73 when I did it a long time ago...). For comparison, an FRC FP motor driven thru an AM Planetary has the same torque as the FTC motor but at a much higher RPM (4800-ish).

The tradeoffs: FTC motors require more complicated electronics, whereas the VEX motors already have a built-in controller. FTC motors require more power, which reduces performance at the end of the match if the robot constantly draws excessive power due to poor gearing choice.
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Last edited by JesseK : 16-09-2009 at 08:52.
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