"The spazzing brain"

The title may sound odd, but thats the only way to explain this. Our team was at a competition, and during the day we’d been having some “issues” with our robot. It would randomly decided to turn off and then on again for no reason, so we brought it to the pit for some maintenance. We were shocked when for no reason (The controller was on, but no tether or crystal attached/in) the robot decided on its own to start driving around randomly and just turning all the motors on and off (Sometimes going faster than was possible using the controller). We tried many things to fix this, but nothing helped. Has anyone else had this happen to them? If so, anything to fix it?

im guessing this is an internal damage problem, you can’t turn the controller on and off with code and if theres no controller plugged in…

that eliminates software and radio problems

must be internal hardware…id use your warranty…for the mean time replace your microcontroller if you can

We had something similar happen with a squarebot my team built for a demonstration. We just used a tether and it started working.

We had the glitch where all our motors started randomly firing like that. We had to unplug and replug everything, reload the master code, and then reload our code several times to fix our problem.

We know a couple other teams have encountered this (usually right before a match, oddly enough) so it might just be a design flaw in the controller. We’ve never had the problem where it turns on and off without us touching it, though. (Perhaps you’re drawing too much current from the battery?)

Did this happen right after a competition? Because it seemed like our robot worked fine before and during a competition, but right after it started freaking out.

Same glitch over here. Since 2007 season and even here in 2008. Bot goes spazzing and such. Tried reflashing master code and user code to no avail. The problem seems quite random - sometimes it would just recover on its own. :confused:

ESD? I can see that happening on those foam mats or other surfaces

I have seen spazzing behavior on two occasions. One was due to a bad extension cable that was intermittently opening. The other was due to a bare wire intermittently touching the metal body of the robot.

I really can’t say what the potential cause for this behavior is other than possible interference. I write the term possible in italics because I try to eliminate all other reasons before I lay blame on something else I cannot confirm or duplicate its conditions. This happened to our robot at the end of a match in the N.C. (Aggieland) FTC tournament as we were removing our robot from the field. Both our transmitters were turned off, but the robot proceeded to start driving and the arm and ring collector mechanism started operating. We pointed it out to the Ref’s and he acknowledged the strange behavior but they were unable to attribute it to anything. Luckly this didn’t occur during that particular match or we would have certainly protested.

Afterwards,we went down our 20 point list and checked everything from cables, antennas, reloaded master and user codes, etc. It didn’t occur again at the competition, but it has from time to time during our build season. We continue to be perplexed about it and have no choice but to attribute the behavior to RFI.

i have had this happen before (which was a problem on my flamethrower robot). all i could say was interference, or maybe you have a messed up motor, because when i unplugged the trigger motor, it worked fine. like others said it could be internal.

I have had this happen as well, but I’m pretty sure that it’s just EM interference and not a hardware problem because my robot worked fine after I put a tether on. Also, this happened to an extreme degree at the first TN state level Science Olympiad competition, because almost no-one had bought frequency crystals other than the ones in the starter kit. everyone’s robots freaked out (I heard this secondhand and it was apparently pretty funny.) They now impound all of the robots and controllers and the only people allowed in the room are the team members and judges.

I even named my first robot after this problem. We had a radio or something at my house that freaked out my robot every time it entered the living room.

octanetripledax, is that your youtube video with the vex flamethrower?

Anyway, if you brain starts spazzing I recommend you use a disposable flash camera to defibulate it!!!

No just kidding, I would use your warranty.

I have also had problems with my microcontroller spazzing upon startup where all of the motors jitter uncontrollably for about 1-2 seconds.

uh, no. i have a youtube account named octanetripledax (no wonder) but i have never posted a video. i don’t even have a camcorder(or at least i don’t know where it is), so i can’t really post vids.

another addition to the spasm is that, it still occurs when programming the controller while motors are connected.