Sunday, September 05, 2010

Motor Troubleshooting and More at Mike's

Today I went to Mike Senna's, to see if we could determine what caused the problem I had with the right foot motor this past Thursday.

We checked wires, the speed controller, the transmitter, trim on the transmitter... pretty much everything. We could not get the right motor to behave abnormally. It always worked perfectly.

Mike decided to open the motor up to make sure there were no boderline solder joints. Everything looked fine.

Of course, putting the motor back together is a bit trickier. It can involve a tiny spatula, dental floss and toothpicks to help keep the springs from dislodging.

I decided to test drive my droid for a good 15 minutes or so in Mike's backyard, to make sure it wouldn't fail after a few minutes. No problems whatsoever, not counting my erratic driving. Don't droid and drive. Or drive and video. Or something.

So, with us unable to determine what went wrong with the motor on Thursday, we turned to other business. For Mike, it was working on his next masterpiece, WALL•E. He's been working on the arms, hands and most recently, the head.

The eyebrows are articulated, and the head will be too shortly.

While he was working on that, I brought over my two extra NPC motors that are intended for droid #2. Rather than spend hours filing the corners down like I did for droid #1, I used Mike's bench grinder to get a head start on these.

I also hacked off the unused side of the shaft, that will be used later to secure the idler gear on the drivetrain.

Finally, Mike helped bend the outer rear logic panel for the dome on droid #2 to more evenly hug the surface of the inner dome, and he touched up some solder work that he noticed didn't look so good on one of my batteries.

So... what to think about the right foot motor? Well, it could be any combination of a few things. In no particular order:

1. Possible inconsistent Vantec RDFR23 speed controller problem. Mike doubts this, because when the right foot motor wasn't working on Thursday, he crossed over the output from the speed controller to the left foot motor, and it worked fine.
2. Possible NPC2212 motor problem. Inspection of the motor did not show any problems.
3. Possible wiring problem. We checked the solder joints, and they all seemed solid. Bending at various angles, even 180 degrees, did not cause any problems.
4. Transmitter problem, possibly caused by extreme trim settings. This seemed plausible, but today the trim was set to the very extremes, and the stick still caused the motor to run, which it didn't on Thursday.

So, I don't know if the problem is solved forever, or if it will happen again. I will be cautious with my next few events, not doing anything too high profile until I am confident that whatever anomaly caused Thursday's trouble won't happen again. If it does happen again, you can be sure I won't touch the system, I'll leave it as-is so it can be looked at by trained professionals. Or whoever I can get.


Anonymous said...

"looked at by trained professionals"

Yea, I called the guys over at Industrial Automation and they said I would have to pay extra because our system is so far out on the Orion arm of the galaxy and they usually do not service this quadrant. They did say there were a couple repair shops near us though, but even they were out past Sagittarius.

Good luck!

Victor Franco said...

Don't trust those repair shops. Stick with Industrial.