Let's Make Robots!

Quick question about voltage regulator?

For a 5v voltage regulator should I buy the LM7805ACT which has 3A 2% OUTPUT TOL 3-TERMINAL or the LM7805SCT which has 1A Pos Vol Reg? The second is slightly more expensive, but they appear to be pretty similar so I'm not really sure what the difference is.

I'm using it to regulate a 9v power source to an axe023 by the way. 



Someone has got to miniaturise this -

Ripsaw-MS1 Remote Gun Tank.


Simple Question about Programming the Arduino

Having built many robots and programmed in several languages, I am new to Arduino and C.  I wish to make a subroutine and place it in a working program.

I have two programs that are running perfectly right now at this moment. I want to combine them together and have the second short program be able to be called many times as a subroutine and be placed in the larger program. I can't for the life of me make it happen.  I usually get some error when I trie to compile it.  I just want to know how to make a subroutine.

Programming help, sharp IR mounted on servo


I am trying to control my bot using a sharp IR sensor mounted on hitec servo with arduino mega. The pseudocode i have so far is as follows:

1. Set servo at 90deg and read IR sensor value
2. If val > 200, then stop the bot for a second
  a. Turn servo 0 deg completely and read ir val
  b. if val < 200 then turn bot left
  c. else turn servo 180 deg and read ir val
  d. if val < 200 then turn bot right
  e. else if cant turn right or left, reverse a bit and then turn the bot 180 degree and go straight.

Arduino questions


i'm from germany and i'm trying to build my first Robot with the arduino Platform.

I've desided to build my own shild for the arduino.

It should be able to drive two motors and to connect 4 -5 servos to the arduino.

The first problems with the L293D Motordriver are solved and I've done that it works and avoids objects.

Today my servos arrived and i tested my shield with the servos.

and then the first problem:

Taking professional looking pictures, with a regular digital camera!

I just HAD to point out this post in the Arduino forums I seen, this guy takes AMAZING pictures! And explains how, even answers all your uber questions. Good for newbs like me! :D Great writeout!


 None of this is mine, just had to make sure this was out there, especially for those up and coming bots! :)

Just an example below:


automatic led emergency light

i am new to this website

can u help how to build automatic led emergency light

i need help for connection and circuit diagram for led emergency light

please help me........................

thanks for ur help

very fast grippers

This has to be the fastest robot hands I've seen...



The best way to manage 2A motors.

Hi all, i'm wondering how i can control a motor with 2A current flow at 6Volts. I'm hacking a toy and the motors that make it to move requires that current... so i can't proceed to my plan A: the L293DNE, because it manages a maximum of 1.4A.

I don't know if exist a similar chip but wiht a higer current limit.

If You have ideas for that... PLEASE HELP ME!

Totally Lost. Totally, totally lost.

What I need is a wheeled, remote controled machine that can go into crawlspaces as little as 4" high and as tight as 4" wide, grab a line securely, and allow me to drag the line out. Estimate that the maximum the wieght should ever be is about 5lbs, with forward and aft cameras and lights (assume the microscopic "spy" type cameras and only a few inches of veiwing area for the light).