Let's Make Robots!

LMR Bot Communication Protocol*

My xmos project proposal included (rather, was refined to include) a communications library to make it easier for the robots to share map data. Then BOA mentioned a communication protocol to allow different peoples' robots to communicate as well. That is a pretty damn good idea, so here's a forum topic to discuss and finalize said protocol.

Sketch to CAD?

I have a paper & pencil sketch of my robotic design and I was wondering if there is anyway to easily create a CAD model by scanning my sketch into the computer. I user Google SketchUp and Alibre Xpress (yeah I'm cheap) and I can't afford anything "more advanced".  If there's anyway to do this, I would love to know, or if you could point me to a tutorial, that would be greatly appreciated.



RC car controlled by PC or PDA using wireless communication

Hallo Everybody !

This is my very first post ! ))

I am doing the robo-project in the university. The main task is to build a robot using wireless technology that can be able to perform number of tasks that are sent from the PC.

NiCad vs NiMH batteries

I wanna buy a charger and some batteries so I've been doing a bit of research on the different types. However the information I found is somewhat confusing and outright contradictory. And in any case I'd like to hear about the experiences you guys have had using NiHM and/or NiCad batteries...

Which would be the better choice? Pros and cons?

What type of wire would I need for a 9V battery?

I'm working on my first project for this year's up-coming sciencefair, but I'm TOTALLY lost! I've been using this old college text book I found at my school's library, but it doesn't help much, so I'd really appreciate the help. For my robot(Technesium) I'm planning on using a 9V battery(and if I should use a higher voltage, please tell me!), but I don't know what type of wire I should use. The book I'm reading says to use No. 12 wire, but I'm still not really sure. Also, I have one more question, how do I determine the current a battery has? Thanks for your help, really!

Where to find a *cheap* range finder?

I'm looking for any place that I can find any type of range finder that's under $100 and I know I'm probably sounding cheap right about now. So far the only one's I've found on the internet are about $1000, and let's face it, that's way out of a kid's league, if they even have a league...Well, thanks in advance!!!:)

 also, anyone know where to get what i think they're called "minicontrollers"? Thanks! 

LMR-IIa Updates

Just a quick post to let you all know the few features that have been added with the IIa sub-upgrade.

The feeds listed on RSS feeds now work again

 blip.tv videos should now embed the correct video

 The User Map is now capable of showing only the user specified. In other words, when you click Location: San Bernardino, CA, US in my user page you'll only get me on the map, and it won't take 20 minutes to load!

TLC5940 anyone?

Allthough these chips are actually called LED drivers they are apparently capable of controlling servos...up to 16 of them :) There is even an Arduino library available for doing so. Pretty cool stuff. But I was wondering if anyone has any experiences with this? If yes then I'd like to know more about it. If not well then consider this a tip to keep in mind the next time you run out of servo pins ;)

Encoders for servo mounted wheels

I have 2 questions, 
- First, when using a C-stamp (programmed using MPlab) is it possible to track the movement of a continus rotating servo so that I dont need to add encoders to know how  much the wheel has turned?  
This is an example of coding that makes 2 servos turn(if it helps):
void goforth(BYTE lp, BYTE rp, WORD t)
  WORD i;