Let's Make Robots!

Hello and My New Arduino Robot Project

Hi Guys,

This is my first post here although I have been lurking for a few weeks now. I am brand new to the world of robots and Arduino. I bought my first Arduino in September and I'm just starting my first robot! My robot's name is Herbert...named after H.G. Wells and kind of an homage to Star Trek....

I plan to have Herbert be a long term learning project. I'm starting with simple motor control and moving up and onward from there. Here is my first video documenting my learning about Arduino motor control using transistor circuits:

Pololu's amazing Black Friday deals - up to 60% off selected products, starting Thursday!

Happy Thanksgiving from Pololu Robotics and Electronics!  I thought that some people on LMR might be interested to hear about our Black Friday sale, so here it is - You can use the following coupons to save big on select Pololu products from Thursday, November 26 through Monday, November 30, 2009:

Any black friday robot sales?

If anyone knows of any savings going on for black Friday on robot parts please post here. If you do not know what black Friday is, it is the Friday after the american holiday of Thanksgiving where a lot of stores and websites have sales. That is 11/27/09.

Barak Obama Worried About Robot Takeover


(jump directly to 1m50s or click on the "watch on youtube" link)


Robotic Ants Farm

Well, Aniss1001 brought up in an other topic the idea of creating a swarm of robots. This reminded me of an idea I had 5 years ago, when I was in the States and building Lego Robots. Funny thing, a quick search on the net at that time revealed several similar projects. Also, my inexperience at that time with non Lego robots didn't let me put it in practice.

So, here's the idea:

10% Off Coupon for LMR Members

Hope this is the correct place to post. If not let me know.

I would like to do more by way of discount, but I am just a small business right now. In the future I hope to be in a position to offer a higher discount. Anyway, you can use coupon code LMRmember at time of checkout.

And don't forget to submit a project to the contest at



Salvaging components

Hello, I'm new to this site and to robotics, it looks like a great place to find knowledge and inspiration about robots so I signed in.

   I am currently waiting for an arduino board to start experimenting, so I am trying to salvage parts and componets from broken electronics (as much as possible)  to save some money. 

Robot gutless and slow....

Ok, so I finally got him put together, and it turns out that he doesnt move worth a damn.... I cant figure out what I did wrong. The tamiya twin motor is set for low range, but it still shouldnt be THIS slow... turning is almost impossible for him... Even on smooth flooring.... I shot a quick video for you all to see and hopefully help me figure out what is going on...



Just saw this posted, scheduled for January 7th. Hope I can get some toys here :



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.


Homemade digital compass

Some time ago OddBot posted this circuit for a homemade digital compass based on hall effect sensors:


Unfortunately CircuitBurn couldn't make it work. However I'm inclined to try again. A cheap DIY compass would be great.

So if anyone has ANY idea as to how this could be achieved let's hear it. It could be an improvement on OddBot's circuits or something completely different and wacky :D

Hooking up a Schmitt trigger (74HC14)

I need to hook up a 74HC14 to clean the signal from a QRB1134 IR sensor. I think I know how but I need to make sure. Could it really be this simple:

*Connect pin 14 to 5V (from Arduino)

*Connect pin 7 to ground

*Connect pin 1 to the signal output of the QRB1134

*Connect pin 2 to the Arduino analog in

*Place a .1uF cap between the 5V and the ground wire

Here is the datasheet and an example I used:


arduino functions

Calculon is discovering the wonders of arduino programming, and he is confused with the function (subroutine) action. He defines and declares a function, but nothing happens. Behold the simplified code:

void loop(){

   goMotor;   //call the goMotor function


void goMotor(){    //activate dc motor via h-bridge



Computers stolen from DAGU

Just letting every one who has placed an order recently with DAGU know that their order will be delayed as our office was broken into again and most of our computers were stolen along with the work van. Since Claudia's computer was one of the stolen computers you should email her again with any recent orders made using the subject:"ORDER MADE PRIOR TO BREAK IN" so we can check it against what has been sent. We will have new computers up and running soon so there shouldn't be too much delay.

Sorry for the inconvenience,
OddBot (aka Russell Cameron)

Problem with Arduino and SN754410 circuit

I arranged this circuit to prevent wires from crossing each other... I'm using using paperclips to make the circuit =). This is what I have so far: 


I tested the circuit and it works! Just one problem: during the "void setup()"part of my code (Arduino), the motor starts to run without any input. I tried to set the PWM pin low, but it didn't worked. How could I fix this? Pull-down resistors? Here's the code I'm using:

Shops for Aussies and Kiwis

Hey everybody out there in Australia. There are many shops out there that you can go to.

- www.robotgear.com.au (theres picaxe + arduino + some solarbotics + heaps of polulu + tank tracks +gearmotors +chassis and other totaly AWSOME stuff) and if you need other stuff, email them and u get them in like a month.

- www.robotics.com.au

- www.robotparts.com

recognizing moving objects vs stationary objects

I just finished building the start here robot.  It works great and I'm really excited to have built my very first robot.  Now what I would like to do is try and have it recognize moving objects vs stationary objects and react differently to objects that move.  What I was thinking is that since the robot is stationary when it looks around I would make it look around one more time.  If it looks at an object on the first pass and that object is at position A and then on the second pass the object is still at position A then it is stationary and the robot would behave as it always had.  If on

Ultrasonic range finder SRF04


I am a beginner. 

I have got a PIC18F252 to run a line follower robot. I would like the chip to run an sfr04 ultrasonic range finder SRF04.  basically if the SRF04 detects an object infront of it, it then turns away.  I am programming in C and am stuck. 

Has anyone got a programme or could somone please point me in the right direction.

 Any help would be great


step-up or joule thief or.. ?

I`m trying to convert the wireless doorbell outside from battery to a renewable source such as solar or wind. My problem lies in that the battery required is a 9v.

My first thought was to produce a high enough voltage to charge the 9v but that might require more solar panels than I have. The 2nd idea was to use a lower voltage battery or super-cap as replacement and stepping up the voltage to 9v. I haven`t taken any measurements of current usage but I don`t imagine it could be more than a couple hundred mA while pushing the button and much lower in idle.