Let's Make Robots!

Break a leg, Wild Thumper!

Byrik

I experimented a bit with video. The weather was perfect for it, as reported earlier.

One laptop with webcam streaming live from my balcony to ustream.tv. And my little 10fps camera on board. Then fool around until the batteries run dry.

Afterwards I found a problem in one of thumper's "legs". It limped. Exploratory surgery confirmed the great fear: a gear is missing some teeth. Oh well, we'll always have the photos.

These are the good gears.

Trying to remember how to reassemble.

Notice the loose tooth.

Output shaft is missing more than 1 tooth.

Wild Amputee ready for action.

Any ideas for a 1x1 drive robot?

Lucky charm: rabbit's foot. Very wild.

 

Comment viewing options

Select your preferred way to display the comments and click "Save settings" to activate your changes.
UltraMagnus's picture

Those gears can't have been very strong if that happened.  I do wish more gear motors used double helical gears.

OddBot's picture

So far there have been 3 incidences where this gear has broken. In all cases it was due to a collision or being dropped where the gear has received a sharp impact. In all cases it was with the 75:1 ratio gearbox which cannot be as easily turned by hand as the 34:1 gearbox.

Yes double helical gears would be nice but no one would pay the price. This is the problem with engineering.

Many have asked that the controller control each motor independantly with an encoder on each wheel but no one wants to pay triple the price for all the extra circuitry which would then need an ATmega1280 to supply enough I/O.

 

 

rik's picture

Don't be a sourpuss, Magnus. Out of 6 x 12 gears only one lost a few teeth. I can't even be sure it happened while driving around. I also dropped the vehicle on that "leg" and the wheel came off. That was the easy fix. I only discovered the stuttering gears after that.

At any rate, my inventions are always as strong as the repairability of the components. I built it, therefore I can fix it (put that on a T-shirt). Except for those gears of course. So Oddbot is helping me out there. That's a whole different kind of engineering. A very kind sort of engineering.

OddBot's picture

As we needed to send you a replacement cable anyway I have included a replacement output shaft from a spare motor. This will get you up and going again.

rik's picture

Excellent! Dankjewel.

I'm glad I took it apart then. Now you know exactly which part to send.

OddBot's picture

I think we'll have to nick name you "Buster" :P

 

Benbo231's picture

Did you hear president Obama's going to be on a new episode (A revisit of a revisit of a revisit of the one where they try to burn the boat with mirrors), which airs in the USA on December 8?