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The non-compass compass guided robot



Is it possible to make a compass from something that was designed for something else and to do it inexpensively? We shall see!




To make a robot navigate according to various headings.

The Catch:

You can't use a compass chip to do it. 

The rules are simple: 

  1. You cannot use compass chip
  2. You have to post your parts list
  3. You have post your code on how to use the 'compass'
  4. You have to prove by video that your robot works
  5. All decisions are final and nondisputable 

How the winner is determined: 

 The winner(s) will be determined by points and votes from participants in  the following manner:

Each participant gets (3)votes and can only use (1) of their votes for themselves.


I will be assigning points to each finished project and they will be on a 10 point scale and the categories that will be: 

  • Smallest Margin of Error
  • Ease of Use
  • Cost to make
  • the quality of the bot page
  • Availability of Part
  • How long it takes  the bot to traverse from the Start Point to the Finish Point 
If you have any questions or need to find out if you idea is acceptable, contact MechGeek200 here on LMR
Start making those bots!!! 


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A few ideas to get those brains cranking 



  • Some Hall Effect Sensors are sensitive enough to detect the Earth's Gravitational Field
  • Triangulating off of known radio stations
  • Encoding a compass(detecting where the needle is by sensors, machine vision, encoding) 


Just a few ideas



Since this corresponds with some of what I'm trying to achieve anyway I'll definately try to have something ready for the deadline of this challenge.

But it's a pretty hard task and so far I'm far from sure that any of the ideas I have will actually work.

We shall see :)

To see if it is doable and to have proof that it's doable or not with current technology and skills.  

I actually had an idea some time ago. The idea was not intended for this but rather a swarmbot concept I've been playing with. But if my homemade compass doesn't work out (or perhaps anyway) it could be used here.

The idea is to place a webcam in the ceiling pointing downwards. The robot will then have 2 LEDs of some sort (perhaps IR LEDs) pointing upwards so the webcam can detect them. Then using image processing I could use my PC to determine the angle and position of the robot and use a bluetooth module (or RF link) to send information to the robot and guide it.

Would that live up to the rules or be considered cheating since the robot needs a PC to guide it?


PS: Like I said the idea was originally intended for building a swarm of tiny cheap robots and I was brainstorming on ultracheap ways of doing localization and robot/pc communication. I was thinking that the robots would blink the LEDs using Morse code or similar to do the robot to PC communication. This way the PC would constantly receive information from all the robots, make decisions and send intructions to the robots.

For PC to robot communication I would put an IR receiver on each robot and place an IR transmitter on a pan/tilt mechanism next to the camara in the ceiling. The IR transmitter could then be pointed at a particular robot to pass intrstructions.

Now the latter bit will not be part of this challenge. I just thought I would bother you good folks with the rest of my idea too :D

It doesn't fit for a number of reasons:


  • It doesn't use something we all have access to(Earth's gravitational field, a public radio transmitter, etc)
  • A robot needs to be fairly autonomous, ie the control systems, power supply, sensors are all contained within it
  • Using something in the local environment isn't in the spirit of the challenge I'm afraid


There are solutions to this challenge, it's not impossible I assure you.


Count me in for this challenge! I'll make the winning robot :D :D (or so i hope :P)

"Engineering are not work, it's a game! :D" 

It seems it is time to start sweetening the pot, so after Christmas I will be unveiling one of the prizes for this challenge.

OMG i just realised how simple this challenge is!
you guys should watch tv more. :P