# Speed based robot

Hi guys, I’m playing a speed based game for my assessment. what speed based drivetrain would be the best to use in this situation (we are playing a game similar to popping balloons in Mario Kart)

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I would recommend a 6 motor drive, three on each side. If the game involves contact or the game has no turns, use a grip wheel in the center and Omni directional on the outer 2. If the game has turns and doesn’t have contact between bots I would say all Omni directional wheels. Both ideas could be in this configuration.

(Do keep in mind he was asking in a vex IQ situation)

Oh my fault. Didn’t see the tag!

It’s been a while since I’ve used iq, but my team does a similar contest at the end of every year. We do mariokart races with three motors, one designated for dropping an item in the racecourse. It’s pretty fun and if y’all are stuck waiting after World’s, I recommend it for entertainment and learning.

Anyways, the best design I’ve seen involved driving two wheels at a 45 degree angle towards the intended drive vector. A third trail wheel keeps the tiny bot stable. It’s easy to turn, has insane acceleration, looks like half an x-drive, and is sqrt2 times faster than parallel wheels. My school deemed it the trill drive, and it can be found if you look in youtube for 2990 Hyperion Trill Drive.

I looked and found 4 second clips of things that may or may not be the actual dive. Can you post the exact link please.

Apologies about that… It’s hard for me to access YouTube on my phone, and I was away from my computer for a bit. Here is the link. Hope it helps you out!

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That is very cool!! I’m see if I can build the IQ version. Thanks for the link!!

What is the approach to programming the trill drive?

It’s pretty simple with two motors, turning can be done by driving the opposite motor from the side you want to turn towards toward the center while holding the other powered wheel in place. This helps with stability, as when you stop turning the vector with the most jerk is directed across the center of the robot and towards the other wheel instead of outside where there’s no support. As for driving forwards and backwards, that’s just driving the two powered wheels towards the center (forwards) or towards the outside (reverse). I guess if you were building the drive for fun and not limited to a two motor drive, you could power the trail wheel, which would give you a little more speed, but the programming challenge of it isn’t really in driving the bot the way you want it to go, but keeping it from tipping over while you do that.

Hope you have fun!

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thank you all so much for your help