Lego Resistor


A lot of you Lego robotics people out there probably know that you can hook up multiple touch sensors onto the same port. Also, you can hook up a touch sensor and a light sensor onto the same port. The problem with more than one touch sensor on the same port is that you can't tell them apart. This is where the Lego 'resistor' comes in handy. A while ago I was trying to think of a way to hook up two touch sensors and a light sensor on the same port, while being able to tell them all apart. It was for a robot that I was building for a local competition (see blockstacking) , so everything had to be pure Lego. I kept thinking, if only Lego made a resistor! The fact is that they do. I realized that a light is just a fancy resistor that heats up enough to produce visible light. So... I came up with the following connection to give one of the touch sensors a slightly different value than the other. The programming to tell apart the three sensors wasn't too difficult. 

     

The picture should be pretty self explanatory. The reason for two lights is that it simplifies the connections. I was flattered when this idea was posted on Michael Gasperi's sensor website.


This Page was made by Rob Stehlik
LegoŽ is a trademark of the Lego company
Revised: May 16, 2002 .
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