Let's Make Robots!


Picaxe code

Hi all,

I've been busy over the past few days studying the Picaxe manuals and trying to understand the coding. I keep reading about how easy it is and it's even called basic, but my problem is, I don't understand any of it.

My electrical and mechanical skills are enough to get me by, but this programming makes no sense to me what so ever.

I've Googled in an attemp to find online tutorials, that doesn't seem to help either.

Can anyone explain how they learned the Picaxe basic coding? That might help me.


The Bromz.

Homebrew tilt compensation?

Honeywell's datasheet on the HMC6343 compass states that tilt compensation is made using data from a built-in three axis accelerometer. I thought that a cheaper three-axis magnetometer- accelerometer combination is much more reasonable for small scale projects, so my question is: What kind of calculations do I need to perform to get a decent degree of accuracy?


Doubts about software development for robots

Hi LMRtians

After doing some programming for my first robot I was wondering (maybe because of my computer science background) if someone uses some kind of notation or software development methods at the hour of programming the robot.
When you are programming simple things like the Start Here Robot (http://letsmakerobots.com/start) it is easy to program a sequence of actions:

  Condition 1: gosub Action 1
  Condition 2: gosub Action 2

From Picaxe to Arduino

When I joined LMR I had just written my first picaxe program. After 16 months I have finally crossed over to Arduino. The biggest problem I found was that all the commands were not in one neat package like the picaxe manuals (Manual 2 in particular).

Listen to LMR!

I came across a website called www.codeorgan.com that turns the code of any website into music! put the url for the LMR homepage in, and it sounds pretty good. I wouldn't expect less from LMR.

Stupid / Beginning Questions

I'm somewhat new to arduino and finally found out about libraries.  Unfortunately I have looked for instructions on how to create one and how to upload an existing library.  So if someone could give me step-by-step instructions on how to get this library i have here sitting on my desktop to something i can use in code. (please dummy-down the instructions).

It would also be helpful if someone could provide me with a small sample code for a robot that uses Ping)))

Code Repository!

Can we get everyone who has got their code to successfully run to post their files here? Ive been looking all over the site for a central area for code, and I cannot find one. If there is one, point me in that direction, if not, lets all start posting here!

Try not to paste lines of code here, lets keep it clean. uploaded files only please!


Name of code,

What it's for

File (zip or IDE compatible file)


What do you guys think?

Arduino Motor Control Code Help

I am currently using a arduino duemilanove, and it is awesome. I have been playing around with it for a couple of days now, and I really like it. Anyways I figured it was time to start to building a robot. I decided to start with the motors. For the motor control I decided to use guibot's tutorial. It worked fine, but the motors only traveled in one direction. Because I wanted the motors to also travel in reverse too I decided to experiment with my own code (on only one motor) that looks something like this:

The challenge of building a 1st bot..


I got my arduino mega in the post a few days back and having been playing around lighting up LEDs. Thought id get started with constructing my 1st bot. Hence i rigged up 2 motors, a dual mc33887 motor driver, a 6v supply and the mega board. Uploaded a sample code to see if it would turn the motors. Voila!! Nothing happens. Nothing whirring, no sound, no ecstasy. No nothing. 

Its quite obvious that my bot wont perform with stationary wheels.

Still trying to find a solution. Images of connection, mc33887 truth table and sample code below.

what is wrong with my code?!

i dont know what's wrong with my code!

i made a simple code that should make my robot simply avoid walls, stuff etc.

i placed SC-QR-1 (my robot's name) upside-down and pressed [F5] (the "run" shortcut) and watched him move his cute little robot legs..     WTF?

the new code seemed to work untill the walk part was over and he started to turn..    ..left.        and then again left and again and again..    etc.

he is suposed to keep walking!!!

What wrong with my code???

#include <Servo.h>

Servo myservoL;
Servo myservoR;
int myservo = 2;
int myAngle;
int pulseWidth;

void setup()
  pinMode(myservo, OUTPUT);

void servoPulse(int myservo, int myAngle)
  pulseWidth = (myAngle *10) + 600;
  digitalWrite(myservo, HIGH);
  digitalWrite(myservo, LOW);

Continuous Rotation Servo & Picaxe

Ok, so I finally got all my gear set up to build robot numero uno, but Im goin friggin nuts trying to control my continuous rotation servos from parallax. Im using a picaxe 18x to produce the code, but no matter what pulsout or servo commands I use, my servo's only go clockwise.I NEED them to be able to go counterclockwise  for my differential drive train to work right. I have read every post on LMR about servos and have tried a lot. I have read their parallax data sheet and that they should respond based upon the pulse width, but no go.