Let's Make Robots!


Sharp IR and voltage drops in large systems

I don't know why I decided to put a Sharp IR (GP2Y0A21) in K-9.  Probably because it's smaller than the HC-SR04 that I'm so much more used to.  In any case, I got a general system assembled and decided to test it using essentially the same branching that I used on Maus.  It seems to go into its obstacle avoidance routine at random.  It definitely reacts when it "sees" something, but also often when there's nothing in front of it.  What I'm wondering is could the "Analogness" of the sensor be what's killing me?

A stepper motor driver where a dsPIC33 both monitors the current and controls the PWM via an L298N.
A few years ago I started building stepper motor drivers.  First it was a simple unipolar driver.  My motors wouldn't rotate faster than 1 to 2 rps.  So I … Read more
Analog, Serial, Motor Control, Audio, Video, Xbee, Bluetooth, PWM... Everything!
Chris was nice enough to send me a little project of his called the 444AVXB. Why the weird name? Well, because it does EVERYTHING. 4: amps of motor driver power (2 … Read more

L298N Heatsink

  Does anybody know of a nice fitting heatsink for the L298N chip?  I know Digikey has a ton of heatsinks, but I am interested in the specific part numbers of heatsinks that LMR users have had positive experiences with.

  I know a lot of people just use salvaged heatsinks, but thats not really an option for me.  Any help would be greatly appreciated!

Schottky diode bridge IC for L298N?

Hi all!

Noob question: I'm using the L298N dual full H-bridge to drive my robot's 4 motors, can someone please give me the name of a chip that contains schottky diodes in a bridge configuration, so I can use it on the outputs to block back EMF? Sparkfun does the same on their boards: http://www.sparkfun.com/datasheets/Robotics/ROB-09571-Serial%20Controlled%20Dual%20Motor%20Driver%20-%20v11.pdf

I know that there are such ICs since I recall a friend using a 16-pin DIP in a similar occasion, but I can't remember it's name. I think it started with "L".

This project is my very first robot project. It has a cybot foot base with 2 DC-motors and 1 wheel in front. I use an Arduino processor as his "brain". For now my … Read more

RepRap Stepper Driver v1.2 and Next Gen CNC

In the picture from top-left, clockwise to bottom-left: the terminal block (24V power up to 13A), the 2 X-axis drivers, the Y-axis driver (blue heat sink), and the Z-axis driver (blue heat sink), the Arduino controller (direction x3/enable x3/step x3), and just below the terminal block there is a small 9V regulator board to shift 24V down to 9V for the Arduino.  Everything is mounted on an MDF board, and the board is mounted with baling wire.


Using Arduino and L298N to control Tamiya Twin Motor Gearbox

I've connected the L298N to one of the motors of the Tamiya Twin Gearbox as per the circuit diagram in the L298N data sheet. But when I set pin 10 and pin 12 to go forward or reverse, nothing happens. The voltage at pin 13 and pin 14 seems to be equal to each other regardless of what I set for pin 10 and pin 12 (with the enable pin on high). This is the Arduino code I have. The diodes I am using are IN4007. I've also tried it with the other H-Bridge and I get the same result.