Let's Make Robots!

IR with Picaxe

Hey guys,

How to use HPWM for picaxe chips.

This information is based on the chip that is used for the 20x2(PIC18F14K22) To get a better understanding of the modes, I suggest referencing this datasheet for further information on the chips features. IMages and info are referenced from both the picaxe 2 manual and the PIC datasheet for the above mentioned chip.

HPWM, what is it?

Viable Potato Batteries?

I'm sure many of us experimented as kids with turning a potato into a battery. I recently re-lived this experience with my seven year old son. It is a fun experiment, but the batteries produce limited voltage and current, so they are not terribly practical.

Rover 5 - 4 Channel Motor Controller: PWM Frequency

I just got hold of OddBot's Rover 5 platform and the 4-Channel Motor Controller.  I'm still fairly new to all this and I'm not sure what PWM frequency to use for the controller.  The datasheet that I have doesn't specify so I'd appreciate any advice you can give me.

Many thanks.

Ultrasonic Ping Module. Range.

Hi All,

I tried to find information about the real distance measurement of the ultrasonic module HC-RS04 but without success.

In the description it is written that range is 0-4.5m (0-5m in another source) but in reality I can only measure the distance up to 2.5m

Does anybody know anything about it?

Is it okay for those crapy sensors from e-bay?

Thank you guys in advance!


Best way to Power an 8 servo - Quadbot

Hi. I want to power a Dagu Qadbot without sources, only batteries, but don't know the best way to Do it. It uses 8 micro servo - 8g, 4~6V, and draw a current that I don't know the specific value as I didn't find a Datasheet.


So, as I'm almost sure that only Arduino will not be able to power the 8 servos, I'm thinking about 2 solutions:


1st - Use 4AA Battery to power - the Arduino i parallel with the servos. This way I'd power the servos directly and just connect the digital pin to the arduino. 

Arduino and ethershield

I have the ethernet shield with an enc28j60 chip. I used the web_server_switch .pde from nuelectronics and followed instructions there and elsewhere on how to get it working.

The problem is I can get it working in a local browser but I cannot access it from my galaxy. I turned on port forwarding for the shield and have checked everything on my routers settings but no success. I am running win7 with a netgear router. Can any networking gurus suggest some things to check?

arduino and SLAM


I am developing a robot platform for children for educational purposes. My aim is to build a sub 100$ bot with arduino brains. I myself is a good programmer, and if I were to do it for myself, I would use an ARM or a better platform, but I have to constraint this project with arduino.

I have already designed some parts, and I have access to a 3d printer, so it is going all well. I already have a servo/sharp IR sensor scanner, and currently I am using a tamiya tracked vehicle for platform.

Micro Robot Controller


This is my new Arduino compatible controller for 2012.

I have crammed as many basic features as I can into a tiny PCB and even written a library to help you use these features. The ability to drive 8 servos (3A maximum) directly from the controller make this an ideal controller for a small Quadruped or robot arm.

Need help with a steering algorithm...


This may be more of a general programming question than arduino specific; I guess the principles apply to all programming languages.

multiple arduino's in one project

im currently working on a octo-pod kind of like chopsticks. i plan on using 4dof legs from the t-hex and some components from vex robotics for the frame. i want to use two Dagu spider controlers. i want to use one for the legs and possible arm, and the other for sencers,etc... i was wondering how can i make the two work together as one.

I2C servo controller schematic and layout

Hello LMRians!


So after half a day of work I came up with this board design for an I2C servo controller (the schematic was done in 10 mins..). So could you please check if this design is going to work as it's the first board I've ever designed?


The schematic:


And the board layout without the GND planes:


With the GND planes:

Send your robot to Maker Faire

Can't make it to Maker Faire this year?

Maybe your robot can!

Last year, quite a few people sent their robots to me to be displayed at Maker Faire. They were a big hit! I even made up some shirts to thanks some of the folk that sent robots from far away.


Dagu Adventure / Mr.General - Is "turn on all the servos" an error of some sort?

So I've gotten my Dagu Adventure Bot running and have successfully been putting code on it.  I've turned off the sound, I've played around with the "light chase" mode and edge detection sensors, and so on.  So I'm pretty confident that the code I see is the code that's making it down to the bot.