Let's Make Robots!

What is your favorite I2C compass module?

I am working on adding compass support to the upcoming v0.87 libaries for RoboPi.


Currently, I am adding support for HMC6352 and HMC5883L based I2C compass modules in the upcoming v0.87 version of the firmware and libraries.

occupancy grid map with canvas?

Im pretty new in this and my english sux, but i do my best :)

Im currently on it to build a Robot based on the Rover5 Chassis with ExplorerPCB and using a Arduino Mega2560 as Controller on ExplorerPCB..

Building a PID oven controller


I am building a PID oven controller based on this project:



I have all of the hardware assembled and I think I am making a rookie mistake.  I am getting an error when I try to upload the code to my Arduino.  It says


No matching function for call to 'MAX31855::MAX31855(int, int, int)'

Stepper Motor Temp.

I've recently been exploring steppermotors and have a very basic question.

What is an average temperature for an active steppermotor. By that I mean one that is turning for more than 75% of the time.

I've searched around and maybe the Wiki article is very informative but it still does not say anything about actual temps.

I'm using the DF controller:

on demand auxiliary LED lamp

Hi everyone, newbe here.

I have been working on an auxiliray directional lamp to operate with the dirction signal of my 40' box trailer. This lamp is to luminate the "wide turn" sign on the rear of the tailer to warn drivers behind me of my intentions so not to obstruct my path while making the tight U-ture with my trailer. Note this light should not be on for a normal turn. This project started with a series of 12v relays when a member sugested to use PICAXE to control the operation. Smart! This why I'm here.

With that said, this is my delema.

Sabertooth 2x25 vs 2x32

Hey everyone,

I'm thinking of upgrading Artie's drive system to use 24V for this motors (the rating of the wheelchair motors), and I'm in a toss-up between the Sabertooth 2x25 and the 2x32.  Now, normally, I would just get the 2x32.  For the same price, you get 7A more current per motor, plus USB feedback!  However, I'd like to get people's opinions.  Has anyone here used the 2x32?  How useful is the USB feedback?  I plan to have Artie run off of a laptop.


Thanks in advance.

Hexapod queries

Hi everyone,

I have been thinking of building a remote controlled hexapod from scratch including the code. However having never built anything like it and having basically no experience with arduino, I have a number of querys I would like your opinions on.

Cost-effective 12v motors

I'm running a small robot project. I'm considering to switch from my 5v plastic motors included in the starter kit, to 12v ones. I'm considering to have the robot weigh 20-30lbs occasionaly, though as is, it can't haul maybe 10lbs very well.

Cost is REALLY an issue to us right now, so I'm thinking of recycling some parts, putting in a used go-cart battery for the (nearly) 12v, but I don't know what I need to in aspect to what gear ratios are required before searching EBay (where I get most of my parts, being on a TIGHT budget.

Thank you for any input!