Pololu Dual VNH5019 & Scooter parts - Motor Fault

Other Hardware Motors, Mechanics, Power and CNC
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Premise:
Anyone see Wreck-it Ralph? I have been working on Sergeant Calhoun's hoverboard from the movie.
Inspired by a probably-joking comment from my BF that it should be motorized, it's now motorized. I don't have a great pic of the setup, but in this image, you can see the two scooter wheels set up in the middle-back. The casters in the front keep me from falling over entirely and there is also one behind on the tail.

Electronics Setup:
Arduino Uno powered by a 9v. Controls are via a wii nunchuck hooked into ports A0, A1, ground, power. Dual VNH5019 shield attached to 2 Razor E200 motors (200 Watt Motor, 24 Volt, 2750 RPM, 11 Amps) and a standard 24v scooter setup (2x 12v 10AH lead acid batteries in series). With the board, wheels, motors and batteries, i'm guessing weight is around 40 lb. Motor/wheel setup inspired by a guy who made a self balancing skateboard using the two motors, wheels, batteries and a sabertooth controller. i went with pololu for the reputation (a friend of mine said you guys were an excellent company, and i'm, admittedly, an electronics noob, but an eager and fast learner) and the fact i found a controller that works for my purposes half the price of the sabertooth.

Problem:
I am getting motor faults. I managed to test drive my hoverboard around without me on it, and it worked fine (well, relatively. i have some steering tweaks to make as it's not as responsive as i'd like). When I myself, tried to ride on it though (bringing weight to 200 or so) it moves, then seems to stop after 10 feet. I hooked up my laptop and set it on the board and it's giving me motor faults (mostly 1, but sometimes 2). I've attached my arduino code.

A friend of mine, who helped me setup the wiring and such on it thinks maybe that i'm not giving the motors enough amps (the batteries power both) and so when i get on the board myself, it panics. I'm able to reset everything (don't have a specific system for resets, yet) to get the motors to go again when i flip it over, but it's a consistently sporadic and inconsistent problem. heh.

Would adding a second set of batteries fix the issue? If so, would I have to upgrade my controller?

NunchuckMotor.ino (5.84 KB)

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What's the stall current of the motors?

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What reduction gearing are you using, I think you'll need it with 2750rpm motors - increase torque to wheels
and increase efficiency, reduce current.

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RE: Stall Current -- i didn't have that logging. I'll get back to you on that this week.
RE: Reduction gearing -- my wheels are connected directly to the DC motor's sprocket, so unless I'm missing something, I don't have any reduction gearing.....?

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In that case they will be struggling I think - a ratio of 2:1 or 3:1 would help greatly I suspect. You'll easily exceed 30A
with those motors and cook the controllers (they are cutting out?).

Your motors are 200W, 11A nominal at 2750rpm, so angular velocity is 290 rad/s, so torque is about 0.7N-m at 11A,
you'll probably need about 2.5N-m per motor to get reasonable acceleration, so about 40A+40A would need to flow
to give that, both way above controllers' max current and beyond your battery I suspect.

Add a 3:1 gear ratio and you'd need more like 15A+15A.... Though top speed would be more limited.