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Do I stand a chance?

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frank26080115:
Here's my new drive train base for my first mini sumo robot
It uses a Tamiya twin gearbox on 203:1 ratio with Tamiya tank tracks using the 1.5" wheels

http://i156.photobucket.com/albums/t31/frank26080115/mini_sumo_bot/DSC02659.jpg
http://i156.photobucket.com/albums/t31/frank26080115/mini_sumo_bot/DSC026582.jpg

I had to cut down on the axle to make it fit within the 10cm limit, I have 1.5cm for a pushing plow with line sensors under it.
It only weighs about 125g right now, the battery pack weighs about 125g too
I will be using 2 photocells with leds and 2 comparators to detect lines only at the front two corners.
And 6 IR phototransistors (3 in front, 2 side, 1 back) to my MCU's ADC, with emitters which will be turned on and off, and the object detection is based on the percentage of IR increased while the IR emitters are on compared to the IR values when the emitters are off. While the emitters are off, if one sensor is significantly different from the others, it will decide that it is an opponent's IR emitter.

Is there anything I should be improving on?

Ro-Bot-X:
Yes. Tracks are the weakest on sumo robots. In front of my Lego mini sumo robot, you don't have a chance.

frank26080115:
So having all the mass on one point is better than having it spread out over a wide surface? Is that why? Or are you talking from experience?

Wouldn't tracks be advantageous if the robot was slightly lifted?

What if I replaced it with 2 solid rubber wheels of the same diameter with plastic wheels on the back?
What if I replaced it with 4 solid rubber wheels with the front and back linked by a rubber band (not touching the ground)?

Will neoprene foam wheels work well? What about use my tank cog without the track with 2 o-rings on each wheel (not connected to the back)?

I'll keep going with the tracked design until everything else is done, then I'll make wheels and compare.

Is torque or inertia more important?

What are the advantages of a large diameter wheel vs a smaller diameter wheel? Why do I see large wheels on almost all sumo kits?

Steve Joblin:
Interested to hear what other say, as I would have thought the same as Frank... I would logically assume that tracks are better because they have more contact area with the surface... I wonder why that is not the case.

paulstreats:
erm.. i did think this also, the larger surface area the more friction.
also 203:1 is a large gear ratio, ive got one of these gear boxes also and they are very powerful, i would be impressed to see anything force it the wrong direction against the gearing (they have a LOT of resistance when the motors are turned off). which brings us back to the wheels. larger surface area more friction.

i would keep with the design personally, but get as close to the weight restrictions as possible

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