Sumobot runs off edge

Michael Mihalka

Folks,

I built a ring for my sumobots. Unfortunately they now have a tendency to run off the edge (when going forward) while they do just fine flat paper ring. Slowing the robots down helps but not enough.

Ideas?
Mike

LoopyByteloose

Isn't running off the edge the end of the bout?
I thought the first one to touch the outer rim is the looser.

If that is the case, I don't see the need to have the Sumobot shut down immediately. You could put a tilt switch or sensor on it to shut off power when it turns over.

I suspect slowing down the robot is a real disavantage because the robot with the most momentum [noparse][[/noparse]the combination of speed and mass] will have more ability to overcome the opponent [noparse][[/noparse]given equal traction]. And since the mass of all of them is nearly the same [noparse][[/noparse]at the maximum limit], higher speed is your advantage. Guys even put doughnut shaped sheets of lead on the wheel hubs to bring them up to the absolute maximum in their class.

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"Everything in the world is purchased by labour; and our passions are the only causes of labor." -- David·Hume (1711-76)········

···················· Tropically,····· G. Herzog [noparse][[/noparse]·黃鶴 ]·in Taiwan

Michael Mihalka

Thanks, but it is running off the edge when no other sumobot is near. I would prefer that it reverse.

Steph Lindsay

Hi Michael,

It sounds like the QTI sensors are not always detecting the white edge. What material did you use for the dark and light surfaces of your ring? Some are far more reflective than others. Did you repeat Chapter 3, activity 3 from "Applied Robotics with the SumoBot" when you started using your new ring? You may need to adjust your program variables.

-Stephanie Lindsay
Editor, Parallax Inc.

Michael Mihalka

Hi Stephanie,

Thanks -- well I did check the sensors on the new ring and the white edge registered under 200. I will check the exercise in Chapter 3 and report back.

Cheers!
Michael

k4shf

Michael,

Did you find a cause?

ruckus49

Half of my class is struggling with this same issue right now. Adjusting the threshold (the divided by number in the example below) seems to do absolutely nothing and the bot runs off the edge anyway. It also is very erradic and will sometimes detect the edge perfectly and about-face with precise accuracy, other times it will fly right past the entire edge without reacting.

Set_Threshold:
GOSUB Read_Line_Sensors
blackThresh = (lLine /8) + (rLine /8)