Let's Make Robots!

Stepper Driver V3 (draft)

Hi all,

I've been working on the driver for the next CNC, V3.

This one should be able to drive bigger motors up to about 2.5 Amps per coil, while providing current limiting.

It's features shold be the following:

- wave, full and halfstepping selectable in software

- I2C and step/dir/enable interface available on board

- home sensors connectors

Below is an iamge of the PCB I layed out:







The Pulse - 2010w07

LMR on the Brain
Sensing the living LMR community since 2008w43.


Pulses are sparse and they shoot by in the blink of an eye. Make sure you have your automatic trigger set up and armed. Or you will miss it.

El Jugador on Giant Bomb

I thought this was pretty cool. I made a few extra El Jugadors and sent them out to the media. Giant Bomb (video game website) got one and put up their video demo.



Video here



Going to Spain :)

Hey, I was just invited to come to


Wehee.. Is any one else going? See you there :)

They asked to see YDM, but I think I will have to make a trata-version of it! Huge sticks and amplifier!

(Yes, I am a one hit wonder, apparently - but hey, a hit is a hit! :)

Controllable battery charger based on max712


Well here it is!! My attemps at building my own battery charger using a sample of the max712, here is the original post that inspired me, http://letsmakerobots.com/node/9272 and special thanks to ezekiel181 !!! 

Bricked! ATTINY2313 Repair with HV Rescue Shield


This blog post contains my build of a "HV Rescue Shield" by MightyOhm.  The High-Voltage Rescue Shield is a high-voltage programming shield that fits on an Arduino.  The Rescue Shield works on 28-pin ATMEGA ICs and on 20-pin ATTINY2313 ICs.  My use/instructions for now only concern resetting the LFUSE (clock fuse) so that the IC can be used with a 16MHz crystal.


I bricked my $3 µC IC on my first attempt at programming.  Recently I found some DIY AVR HV programmers that could be made from stuff in my lab.

Robotics Engineering WPI Class of 2014

Hello fellow LMR'ers,

I just wanted to create a blog post because I haven't been active on the site in a long time, but that's for good reason.  

I've been really focused on my school studies, and being a senior in high school, I also need to focus on college applications, financial aid, ect... 

Speaking of College, just today I received an admissions letter from Worcester Polytechnic Institute stating that I have been admitted to become a part of the WPI class of 2014!!!!! 

Optointerrupters and Arduino

Ok, I have a pair of optointerrupter modules (just an IR LED and a photodiode paired together basically) and I would like to find out how to use them as distance sensor with an Arduino. Could anyone set me up with some really basic code that I could play around with just to get me on the right track?


Hello All

This is my first post on LMR. My inspiration came from a video I saw by Boston Dynamics of their robot Big Dog. I started off originally with a hexapod but during the design stage it became clear that it will be to expensive as I was looking to use high precision brushless DC motors and lots of custom machining. I then turned to less legs and more strict parameters.

All parts/components needed to be:

made using simple tools.

individually not to expensive

New robot reqs

With my background as a software developer, I know the value of setting requirements before you start working on something.  If you don't, you end up aimlessly adding features or tweaking functionality until you aren't really sure what you were trying to do in the first place.  So I am going to lay out my requirements for my new robot (whose parts I just ordered last night).  This first robot is meant to be a proof-of-concept.  My long-term plan is to use the knowledge I gained here to create a second, larger, stronger, more functional robot.


So I was going to post a blog with a picture but I can but the picture was about my robot  SOLAR-1. It has a IR sensor, a Light sensor, 2 LEDs, Picaxe mircocontroller and that all of the major part of the robot. It will avoid object and when its in a dark place it will turn two a very bright blue LEDs located above the light sensor. Thats all for now cheack back next time for some updates


I'm new here and to the world of hobby robotics.  Here is a bit of background on myself.

I discovered this world of hobby robotics when I was researching purchasing a roomba.  I've been looking for a new hobby for some time and this looks like a lot of fun.  I work as a software developer for a large consulting firm, and I always wanted to do some coding for my own amusement, but I could never find anything that interested me enough.  But robots are really cool.

Make over?

Just to explain the changed avatar:


This replaces my 2003 model. And is improving my sight by leaps and bounds. I really should've had my eyes checked years ago! Before LMR even!

The mbed system...

What do you guys make of the mBed system? Its gaining ground rapidly, and it has even entered the meager library of Fritzing parts. Now that's saying something. Anyways, looks like a great system. Breadboardable, ARM based, has an online compiler where you can write code and save it to the cloud (so it's cross platform and you have your data everywhere there's internet). Not an Arduino, but looks good for the aspiring geek looking beyond the Ardy.

So, what do you think of it?

Tripie v1

Well, I got a new work in progress its called Tripie.

 It will use 3 DOF per leg, the first design its based on the mini-hexapodinno.

 This is the rendered image how will looks.



Microprocessor: unknown

Sensors: sonar

Servos: 9ge

Plastic parts:  home made

Starting date: unknown


Comments are welcome..



Swiss Cow Head Laser Distance Probe

"Moooooooo" project is still on course........

Basic idea is to attach the Head to a Theo Jansen four legged chassis blogged here.......

Had some great fun creating a PolyMorph Cows Head.

Using a Skinning technique i could make a really thin layer of PolyMorph.

This means that it is amazingly Translucent - for adding lights.


In the Picture above you can see its secret laser system.

Science project

I've decided to do a light-following solar panel with an Arduino for my science project. However, I'm kinda stuck. I'm confused on how to get the numbers to compare, then tell the servo to go to that position...


Thanks for the help!

Trying the arduino

So i got bored tonight and decided to try and use the one and only arduino i bought which has been laying around for a few months. I made a really quick chassis out of shapelock then used some zipties to hold everything down (literally everything). Wired up a 293d, and i think a sharp? Looked through some code other users had posted and tried to get my robot to work. The motors run fine, i'm using a 6v battery pack for the motors while having it plugged into my comp to power the sharp. For some reason, and i'm almost positive it's the code, the sharp won't respond.

Computer Parts Salvaging

My work occasionally has a surplus computer sale, where they get rid of old or non functioning computers.  So I picked up a nonfunctioning one complete with keyboard and mouse for free.computer_salvage_010.jpg

 This is also probably a good time to show you my basement workshop.


The whole setup takes up a corner in the basement next to the central vac.