Overview
Things
Story

Project Overview
Construction
Troubleshooting
Alternative Materials

Custom parts and enclosures
Schematics
Code
Credits
Comments(3)

SciJoy

Published October 22, 2016 © CC BY

Exploring Encoders - Step Trackers for Motors

Build Absolute, Incremental, and Quadrature Encoders

BeginnerFull instructions provided4 hours7,098

Exploring Encoders - Step Trackers for Motors

Things used in this project

Hardware components

Adafruit Break Beam

You can also use LDRs and LEDs.

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DC motor

The shaft diameter in the CAD file is 3mm. You might need to adjust this according to the motor you pick. A smaller and cheaper motor is: https://www.amazon.com/RS-550s-18v-Electronic-Controlled-Replacement/dp/B00TE42PME/ref=sr_1_1?ie=UTF8&qid=1477015531&sr=8-1&keywords=rs550

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Arduino UNO

Any Arduino should work.

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Breadboard (generic)

Breadboard (generic)

You can use this instead of soldering.

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Jumper wires (generic)

Jumper wires (generic)

If you are using a breadboard, you can use jumper wires.

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Motor Controller

You can just use a battery and a potentiometer.

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OpenBeam Starter Kit

You don't have to use this. You can use other materials to construct the stand.

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2 Pin Board Side

You don't need this if you are just going to breadboard the project.

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2 Pin Sensor Side

You don't need this if you are just going to breadboard the project.

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3 Pin Board Side

You don't need this if you are just going to breadboard the project.

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Contact - 22-28 AWG

You don't need this if you are just going to breadboard the project.

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3 Pin Sensor Side

You don't need this if you are just going to breadboard the project.

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Hook-up wire (solid 22-28AWG)

You don't need this if you are just going to breadboard the project - use jumpers.

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Header pins

You don't need this if you are just going to breadboard the project.

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Solder (Generic)

You can just use bread boards. This is a good tutorial for learning how to solder:https://learn.sparkfun.com/tutorials/how-to-solder---through-hole-soldering?_ga=1.113903495.1265549123.1409440336

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Prototyping Board

You don't need this if you are just going to breadboard the project.

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Screw Terminal

You don't need this if you are just going to breadboard the project.

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9V battery (generic)

9V battery (generic)

You can use power or PWM on Arduino instead.

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9V Battery Clip

9V Battery Clip

You can use power or PWM on Arduino instead.

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AA Batteries

AA Batteries

You can use power on Arduino.

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AA Battery Holder

You can use power on Arduino.

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Software apps and online services

Fusion 360

Autodesk Fusion 360

This is how we created our drawings.

Arduino IDE

You'll need this to upload the code.

Hand tools and fabrication machines

3D Printer (generic)

3D Printer (generic)

You could also cut the templates out of cardboard.

Crimper

You don't need this if you are going to breadboard the project.

Soldering iron (generic)

Soldering iron (generic)

We like Hakko. You don't need this if you are breadboarding the project.

Story

Project Overview

Encoders are like Fitbits for motors. Depending on the type of encoder, they can keep track of the distance the motor traveled, the direction, or the exact angle it has turned. Typically, encoders are really small and spin at high rates. To investigate how they work, we made larger slower models of them. This project demonstrates how incremental, quadrature, and absolute encoders work.

Construction

Encoder Disk

A rotary encoder is a wheel with slits that is attached to the shaft of a motor (or other device that you want to monitor the position of). Our encoders were 3D printed.

Structure

Our structure is made out of OpenBeam. We wanted something sturdy and adjustable. We wanted to be able to move the sensors up and down to align with each other and closer and father away from each other if needed. The mounts for the motor and sensors were made for OpenBeam, but you can use other materials you have.

Sensors

We used Adafruit's break beam sensors. You could use LDRs and LEDs. The transmitter just needs to be powered. It can be powered with 3.3-5V. We use 2 AA batteries. The black is ground and the red is power. The receiver has a white wire. This is the signal wire. which goes to digital pins 5, 6, and 7 of the Arduino. We power the receiver via the Arduino (you can power both the transmitter and receiver via the Arduino ).

Motor

We have a larger motor and a motor controller wired to a 9V battery. You can use a smaller motor and a potentiometer to control the encoder. Just watch out for the voltage rating on the motor and change the diameter of the opening to fit your motor.

Troubleshooting

The break beam sensors use IR that can sometimes transmit through the material you are using. We had to paint our 3D printed material. The cardboard worked just fine.

We had a bad crimp causing one break beam to always ride high. Using a multimeter, we determined there wasn't a short on the board or an issue with the code.

Alternative Materials

For the detectors, you can replace the break beams with LEDs and LDRs.

You don't have to use a 3D printer. You can just cut encoders out of cardboard.

The motor we used was one we already had. Smaller motors will work too.

You don't need OpenBeam. You can make the stand out of things you already have around your house/workshop/classroom.

Custom parts and enclosures

Schematics

Code

Credits

SciJoy

SciJoy

7 projects • 15 followers

We run a YouTube channel where we share what we are learning and building with others.

Comments