ECE5320 MECHATRONICSASSIGNMENT#01: LITERATURE SURVEY ON SENSORS

AND ACTUATORS

TOPIC: POSITION SENSORS/ROTARY ENCODERS

Prepared by: Berk Demirgok

Dept. of Electrical and Computer Engineering

Utah State University

3/15/2012

Content

Overview of position sensors

Applications of position sensors

Types of position sensors

Applications

Content

Study Rotary Encoders in position sensors

Specifications

Purchasing

References

References and To explore further

“Mechatronics – An Integrated Approach” by Clarence W. de Silva

Wikipedia Mechanical measurements by Thomas G.

Beckwith, Roy D. Marangoni, John H. Lienhard

http://www.automationdirect.com/adc/Overview/Catalog/Sensors_-z-_Encoders/Encoders?source=google&keyword=rotary%20encoders%20incremental&type=search&gclid=CMOT44X19q4CFQUZQgodyHEJzA

References and To explore further

http://www.electronics-tutorials.ws/diode/diode_8.html

http://www.electronics-tutorials.ws/io/io_2.html

http://www.eowave.com/products.php?prod=21

http://www.autonics.com/products/products_2.php?big=01&mid=01/06

References and To explore further

http://www.sensors-transducers.machinedesign.com/guiEdits/Content/bdeee4/bdeee4_3.aspx

Overview

 A position sensor is a device allowing position measurements.

The sensor can either be to some fixed point or position or from some fixed point or position. 

A position sensor can measure any positions, such as linear positions, angular positions and rotary positions.

Types of Position Sensors

Linear Positions

Angular Positions

Rotary Positions

Major Applications

Servomotors Amusement equipment Music live control Computer game joysticks Steering wheels Robot applications Industrial applications

Rotary Encoders

Rotary encoders are also called shaft encoders.

Rotary encoder converts angular position of mechanical movement of a shaft or axle to an analog or digital signal.

Generally, digital signal is preferred.

• http://www.google.com/imgres?q=rotary+encoders&hl=en&sa=X&rlz=1C1CHFX_enUS474US474&biw=1024&bih=624&tbm=isch&prmd=imvns&tbnid=2Rz18G1gJ9BnXM:&imgrefurl=http://www.karacnc.com/products.html&docid=bc9LaH0jfjAktM&imgurl=http://www.karacnc.com/images/rotaryencoder.jpg&w=277&h=277&ei=FT9pT431IqeYiQKW4dDbBg&zoom=1&iact=hc&vpx=270&vpy=292&dur=807&hovh=221&hovw=221&tx=102&ty=133&sig=103248373012637440328&page=5&tbnh=133&tbnw=136&start=72&ndsp=20&ved=1t:429,r:6,s:72

• http://todbot.com/blog/wp-content/uploads/2008/06/rotary-encoder-closeup-300x221.jpg

How it works?

Rotary encoder works just like an optical encoder.

Lights from LED or infra-red light visible semiconductor diodes goes through a rotating encoded disk which contains the required code designs in binary grey code. Then, photo sensors examine the disk while it is rotating.

How it works?

While the disk rotates, an electronic circuit procedures the information from rotating disk into a digital information in binary code.

Converted digital output is in binary code form because, binary code helps controllers to determine the actual angular position of the shaft or axle.

How it works?

After the output converted into digital signal, a rotary encoder can helps us to know position or distance. Moreover, rotary encoders also can provide information about speed, revolution.

Illustration of how it works

• http://en.wikipedia.org/wiki/Rotary_encoder#Incremental_rotary_encoder

Types of Rotary Encoders

Incremental rotary encoders  Delivers only cyclical outputs when the

encoder is rotating. Incremental rotary encoders can get one of

three following signal categories: Quadrature Single channel Pulse Direction

Types of Rotary Encoders

http://img.deusm.com/designnews/289/289447-Incremental_Optical_Encoder.jpg

Incremental rotary encoder looks like this

Types of Rotary Encoders

Standard rotary encoders

http://www.industrystock.com/pressenewsimages/orig/cde86e815031c45457c1ba273b8c88d0.jpg

Types of Rotary Encoders

Modular rotary encoders  Modular rotary encoders are the most

sensitive to motor shaft run-out and axial movement. They are commonly used in servomotors.

http://img.directindustry.com/images_di/photo-m2/miniature-optical-incremental-rotary-encoder-734405.jpg

Types of Rotary Encoders

Kit rotary encoders

http://images.tradekool.com/199762700/Encoder-Module-Kit-Encoder-Optical-Encoder-Rotary-Encoder.jpg

Types of Rotary Encoders

Single channel rotary encoders

Applications

Rotary encoders have very wide-range application areas and some of them are mentioned as: Industrial Controls Robotics Photographic Lenses Cellphones Computers Automotive

Purchasing

Rotary Position sensor can be easily purchased from many online stores

Here is some good web-sites to look if you want to buy rotary position sensor. www.digikey.com www.mouser.com http://honeywell.com www.eowave.com

Purchasing

http://www.marshbellofram.com/servotek/Rotary%20Encoders.JPG

Price Range Research

Light Duty use rotary encoders

$25-$125 Medium Duty use rotary encoders

$75-$200 Heavy Duty use rotary encoders

$150-$300

Questions?