Analog Experimenter

If you have the MakerBit (without the green/orange connectors for motors), click here or on the image on the left for alternate instructions specific to that board.


The Analog Experimenter is a program that combines the regular MakerBit program for touch sensing with the function of using 1 photocell to control a servo, and another photocell to turn an LED on when the ambient light level gets dark.


It can also display the values read from the A0 and A1 analog inputs on a connected LCD text display if you have one attached.


Note that A0 and A1 are the same pins used to control the audio playback module, so you can use the mp3 player OR the analog inputs, but not both.  For that reason, you'll need to disconnect the audio playback module if you want to do these analog experiments.



Some Simple Experiments


Connect the servo motor and a photocell to the MakerBit as follows: At the area below the maker:bit and the center black connector for LED’s is a row of 3-pin connectors  labeled from P5 to P16. The black pins at the top are connected to ground, the center red pin is for 5 volts, and the signal pin (the white connector) is at the bottom. The servo motor has three wires and they should be plugged into the P10 connectors with the yellow wire in the white signal connector, as shown below.  


Project Use Ideas:

Because the servo is a special kind of motor that, instead of spinning, moves to a specific angle from 0 to 180°, it could be a "pointer" on a project, such as indicating the amount of light being received by the photocell.

When you see the moving arms of a robot, the wheels turning on a car, or the rudder on a radio-controlled airplane, those are all controlled by a servo.

The plastic arm for the servo (included in the MakerBit kit) can be attached to a door, or even a drawbridge in a model of a castle.

There are also small holes in the plastic arms that can be used to attach a string so that when the servo arm moves, it can pull or relax the tension on whatever it is attached to.


Have you discovered other uses? Let us know about them!

When you start up the MakerBit with these attached, you can change the amount of light that falls on the A0 photocell, and the servo arm will move in proportion to the amount of light.  You've just made a "light meter"!


At the same time, the MakerBit will monitor the other photocell sensor connected to A1, and turn on the LED (and vary the brightness) as the temperature reaches as certain point.  You can adjust that temperature point by using a small screwdriver to adjust the blue trimmer for "A1" on the MakerBit board.

Attach an LED cable with an LED in socket #5.  That will be the socket with the grey and violet wires, plugged into the upper "LED1" connector box.


Then plug another LED cable into the Analog (blue) connector box on the MakerBit. Insert a photocell into the socket pair for "A0" ("Analog input 0", the wire pair with the red wire on the outside edge), and another photocell sensor into the socket pair for "A1" ("Analog input 1", the black/white wire pair.)


MakerBit

MakerBi+R