Let's Make Robots!

URGENT! Need help with some ideas to "improve" the insect bot

I have about 4 months to make a project but I have to give a presentation tomorrow about what I'm gonna do in the next 4 months so I need some ideas guys. I have decided on making a basic legged robot which avoids obstacles and since it's very short for 4 monts, I was wondering what else can I add to make it more complex ?  I was thinking of adding a bluetooth module for controlling it via a laptop or smartphone and a gps module for coordinates or something .

What does this circuit do?

Found this today... I'm trying to figure out what it does. Any guesses?

Jitter problem with TLC5940 controlling 12 servos

Hi guys, I am a beginner in arduino and robotics. Recently I am starting a project for a 12DoF hexapod. I am controlling the servos(Tower pro micro servo SG90) using a TLC5940 based on this schematic by John Boxall:

From the schematic,I changed the LEDs to servos and attached a 2.2kOhms resistor between every output and the external voltage(in my case external voltage is from 4x1.5V AA battery)

CV and micromotion algorithms

Interesting.  I wonder how difficult it would be to port it to OpenCV?

Need a coupling for a 28BYJ48 stepper motor...

I'm building a device to pan a small camera. I'm using the uber cheap 28BYJ48 stepper motor. To mount the camera to the stepper motor I need a small coupling. One side should be bolted to the axle of the stepper motor, the other end should have 1/4"-20 thread (standard camera thread). Is there anyone here that could make me such a thing? I would like to build a decent, sturdy device so I don't want to resort to hotglue... I'm located in the EU (Belgium), any European people here that can machine such a coupling?

Drawing of the piece (dimensions are in mm):

Cheap Simple Robots


I am starting a Robotics and Computing club at my School and need some ideas for some cheap, simple robots that I can get the kids building.

The idea will be that they / their parents buy the materials based on info that I supply and I help them build there robots during the club (aprox 6 hours total).

I don't really want Maplins type toy looking robots and anything with a microntroller is hoing to be to expensive. The topic for the term is renewable energy and climate change so recycled robots may be on the cards?

Powering an Arduino NanoATMega328


I have just put together and ordered some parts to build a value for money robot that I will be demonstrating and getting the kids in my school robot club to build.

Do H-bridge resistor values need to be calculated, or can they be played by "ear"?

Hi All,

I followed an H-bridgeschematic from a post by ignoblegnome and the resulting H-bridge worked perfectly.  I looked around online and saw some h-bridge schematics without resistors and also with resistors.  I wanted to know if resistors were necessary in h-bridges?  And I also came across a specific formula that is used to calculate the base resistor needed for a certain transistor.  Do these calculations need to be followed religiously? 

The Parallella Board?

I was wondering what people think of this board and the supercomputer that this guy built with them.

The Board:


This guy built his own supercomputer with 8 of them (each with 18 cores) wrapped around a gigabit switch and a couple of Intel I3 NUCs.

The Supercomputer: