Let's Make Robots!

12V LED Dimmer in Arduino


I am trying to make a 12V LED strip dimmer and found this from arduino forum.


This was working for my first attempt but transistor seems like dead after 2nd try next day.

Any idea for better solutions? Thanks in advance for anyone.


What's proper way to make multiple XBee controller?

I am not so familiar with XBee module. Only know how to communicate one to one and I am planning to make one controller that able to control multiple devices with XBee. What I can think of is have all remote devices with different PAN ID and switching PAN ID on controller every time. However I don't feel that's the proper way to do it. So, I am here to search for help and advices. Thanks for anyone who can help.

Connect 2 brushless motor w/ single LiPo battery

I am trying to connect 2 motors with one battery. It works OK but 2 motor doesn't spin in same speed or start at same time. So, was wondering something wrong in my setting? Should I add something in between to have 2 motor kinda sync together?

In the image I have point out A,B,C,D,E spots. If I need to add anything on those spots? Or should I just using 2 batteries instead of one? Furthermore, if I wanna make quadrotor or six, eight motors and so on. What's the best solution?

I thought it was one of the rule to join the great community, so I spend this weekend to make this "Start Here" robot by using Arduino with motor shield from … Read more

Multiple Array in Arduino

Happy new year LMR,

I am trying to modify the buzzer code from arduino sample. I wanna try to keep it simple and easy to call a function to manage different tones. For example:


Positive terminal RGB LEDs

Recently I got few 10mm RGB LEDs. The strange thing is: the longer pin is positive? This is what is says on eBay:


10mm Ultra-Bright RGB LED 7000-9000 mcd

IK programming for Arduino?

Everything seems working now for quadbot:

Now, the programming is the diffecult part for me. Anyone can show me which direction I should go for IK programming or any book I should read to understand the concept?

Thanks a lot!!

Does anyone knows the conflict between Servo and Tone library?

I am trying to add the Tone in my arduino device with Servo and Tone library but there's an error:

Servo\Servo.cpp.o: In function `__vector_11':
C:\Users\Me\Documents\Arduino\libraries\Servo/Servo.cpp:103: multiple definition of `__vector_11'
Tone\Tone.cpp.o:C:\Users\Me\Desktop\arduino-0021\libraries\Tone/Tone.cpp:421: first defined here

Any clue? Thanks for any ideas.

How do you survive and building bots?

I have always wondering, What all LMRs do for living? I know some of us are really building robots for daily bread. Well, I have to save every penny to build robots and also lieing to my wife for new parts as "Oh! those package are just exchanged parts~". 

Actually, I am an interactive web designer, not much relate to robot.

So, how about your story??