Let's Make Robots!

Um, this is wicked cool - micro laser scanning quad prop air platform

What happens when you put a laser scanner on a quad flying platform -> here

Just what I need for around the house.

Servo Advice

Hello LMRers,

I've never used Servo's nor microcontrollers in any of my robot projects, always computers, dc continuous or steppers motors, and solenoids!

So, last Christmas Santa gave me an Arduino Duemilanove (I love Santa).

Now, I'd like to get some steppers.

I was wondering general advice, shops, prices, and other considerations of my nerdy bretherin 

This seemed like pretty good prices .. http://www.hobbypartz.com/servos.html  

Ideas for motor speed control

I have an idea of how to do a electronic speed control for some DC motor (H-bridges).
I built this circuit and it works pretty well.  Its a PWM generator based on this great tutorial .  I had to convert it to a NE556 instead of a NE555 but it works well with a 100K linear pot..


Anyone have any experience with an ooPIC?

Seems a bit expensive, yet looks to have a pretty extensive compiler.


 Loki's Head     Loki's control interface       Loki grew a head recently in order to support some experiments with stereo vision.  The two lasers are … Read more

Oh, where did I go wrong? - Circuit Quiz (Mystery Solved!)

I built this circuit:
a TTL input on s0 is supposed to turn on Motor 1, and a TTL input on s1 is supposed to turn on Motor 2.
Why the heck does both motors go on when either S0 or S1 go to 5V?

It never ends to amuse me how many ways I can goof stuff up...



Has anyone used stripboard or pc boards before?

Has anyone used stripboard or pc boards before?

Do it yourself PCB experience

My question is for all the people who have etched their own circuit boards (BOA, JIP, Fritsl?, Others?).
I would like to know:
1. how many times you have made your own circuit boards.
2. how long does it take. Is it faster than wire-wrap or "free-form" soldering?
3. how many boards have you made in a run?
4. have you ever tried commercial sites? how would you compare vs doing it all yourself?
5. what is the start-up costs?
6. what do you do with the spent chemicals?

How is inter circuit communication addressed in I2C communication

Doing a little reading on this - it appears that it was initially a 7 bit address scope. Wikipedia currently has it listed as such.

However, BOA has informed me that it is now 13 bit.  What IS the REAL address scope?  If I have a IC widget and I want to talk to another one, how do I speak to it.  Knowing the correct address, I suspect, would be a good beginning.