Let's Make Robots!

Pololu A4988 and Nema 17

Hi, I'm trying to build a balancing robot. I bought 2 x A4988 driver and 2 x Nema 17 motor.

Capacitors for smoothing servo current surges

I've built what I thought was a nice clean approach to the oft-recommended practice of parking a 470uf cap on the power lines to my servos. I have 6V coming from my voltage regulator to the postive/negative bus strips on a small PCB. I've pulled a positive and negative wire off of the bus for each servo (3 servos total) and put a capacitor across each pair of wires. One servo should then connect to each pair of wires.

LMR Intro Video



Whilst editing my newest video I found I was getting a little sick of just having an LetsMakeRobots static image at the end of my videos. Because of this I thought I would throw together a short LMR clip to make it look all fancy and stuff.

You are free to download these and use however you like.

The YouTube video is of the clip.


Download links can be found using the link below:

Inverse kinematics

Been trying to understand inverse kinematics for programming my quadruped Crap-Crab. I started out by reading Wikipedia's version, which lost me completely (WTF?). But then I found the explanation by this guy and it turns out, as I thought to begin with, that it's simply a matter of applied trigonometry.

Here is exactly what I need in a nutshell:

Wild thumper slow comunication through ethernet TCP

Dear Sirs.

First of all thanks for your time, help and sorry for my English.

I'm am working in a Final Degree project with Wild Thumper 6WD chassis, T'Rex Controller and Arduino MEGA 2560 + Ethernet Shield + Gamepad (connected to the PC)

The communication between T'rex Controller and Arduino Mega is made through I2C BUS (using the T-Rex tester example code from DAGU). Then I created an application using Windows Presentation Foundation which connects the Arduino Shield (using TCP socket) and a gamepad connected to the PC by USB (using AForge library).

Thermistor error with the MK8 extruder.

Dear: LMR

STL Viewer (beta)

Rotate: |


hi !
 we are creating a drawing machine that does mistakes and turns red (LED)

does Balancing Robot PID values become obsolete as motor battery diminishes?

Hi All,

I'm wiring up yet another attempt at a balancing robot (smoked a motor driver IC last time) and I just thought of something.

If I connect the motor driver to a 12V battery, then tweak my PID parameters, everything is going to go smoothly at first.  But then when the 12V battery diminishes, to say 9V, the motors will be a bit less responsive, and then I'd have to go ahead and tweak the PID parameters again.

ICs chips for sale

If you're looking for IC chips for your project now, this is the greatest offer to go.

30% OFF on all ICs chips on ICStation

Thanks and enjoy your day!


World Maker Faire NY 2015!

June 11, 2015:

I'll be hosting a Google Hangout this evening at 4:00 PM EDT to do some planning for the faire. It will mostly be Rick and I, but anyone is welcome to join and contribute. Reach me on Google+ if you want to be added. (https://plus.google.com/+AndrewTerranova/posts)