Let's Make Robots!

Bluetooth module worth keeping?


Well here is the problem, I have a Bluetooth module and I did use it on a previous bot, but it had a library specifically for that module so I was only copying a pasting code to get it working.

Looking for a cheap long range distance sensor.


Would anybody know of a cheap long range distance sensor? 

Something with a max distance of 2.5 to 3 meters. It would be for my nitro rc car, I dont totally trust my radio system so a distance activated fail safe would be really reassuring!  

Accuracy isn't ran issue, but price is. 


Thank you in advance! 


Can these displays be controlled by a Picaxe?

I found these 2 displays in an old cd/casete/radio combo and was wondering if they were worth keeping, 
and if they could be controlled using a Picaxe.
I know that a picaxe can control a display buy using a serial interface but these ones dont have that,
they have about 30 pins, not including the ones for the back lite. 

A IC form of NPN transistor ?

Is there  such thing as a DIP package of transistors ? (not sure if that is the right way to put it) 
I need to control 12 digital connections and putting 12 transistors on a PCB will take up a decent amount of space 
so I was wondering if there is a chip like version.
If possible a high voltage ~40V and high amperage trnasistor would be perfect it it exists. 

Salvaging an old motion triggered light

The other day I found this in our local garbage dump:




I have been trying to figure out its wiring diagram using a multimeter.


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;

ASIMO Robot learns object identity

This is extreamly cool

A mini relay like chip?

Here is the setup, I need a picaxe to "push" 2 buttons when it receives a high digital input. 
I will be using a picaxe08M and will have 2 digital inputs(2 buttons) and to digital outputs to triger the relay.
I need somethink like a relay but much smaller, about the same size a the picaxe chip.
It only need to handle 5V.
Anybody know of something that would do the job ? 

Which rechargeable battery to choose?

Lately I've been a bit more careful about how I spend my money on my robotics projects (wasn’t able to get a summer job this year) and I have notices one big problem: batteries!