ECE 5320 Mechatronics Assignment#01: Literature Survey on Sensors and Actuators Proximity Sensors

1. ECE 5320 MechatronicsAssignment#01: Literature Survey on Sensors and Actuators Proximity Sensors Prepared by: Alyssa Wahlin Dept. of Electrical and Computer Engineering Utah State University T: (435)797-2840 W: http://ece.usu.edu 3/9/2012

2. Outline • Reference list • Further Information • Major applications • Basic working principle • Typical configuration • Major specifications • Limitations • Different types • Manufacturers • Styles • Cost ECE5320 Mechatronics. Assignment#1 Survey on sensors and actuators

3. Reference list • http://www.sensors-transducers.machinedesign.com/guiEdits/Content/bdeee4/bdeee4_7.aspx • http://www.automationdirect.com/static/specs/proxterms.pdf • http://en.wikipedia.org/wiki/Proximity_sensor • http://www.meadinfo.org/2011/04/sensing-distance-of-inductive-proximity.html ECE5320 Mechatronics. Assignment#1 Survey on sensors and actuators

4. Further Information • Example of hands free technology • http://www.youtube.com/watch?v=mq87l10eGHg • Short clip about proximity sensors • http://www.youtube.com/watch?v=qznlwbCVQ1c&feature=related ECE5320 Mechatronics. Assignment#1 Survey on sensors and actuators

5. Major applications • Roller coasters • Parktronic • Car bumpers that sense nearby objects • Cell phones Proximity sensor on roller coaster http://www.flickr.com/photos/spacecamp/4544652955/ ECE5320 Mechatronics. Assignment#1 Survey on sensors and actuators

6. Major applications (2) • Automation manufacturing • Vibration measurements in rotating shafts • Conveyor systems • Counting items • Position of elements Proximity Sensor on Chocolate Conveyor Belt http://www.pepperl-fuchs.com/global/en/3786.htm ECE5320 Mechatronics. Assignment#1 Survey on sensors and actuators

7. Basic working principle • Detect nearby objects without physical contact • Emits electromagnetic field or beam to sense for changes in it ECE5320 Mechatronics. Assignment#1 Survey on sensors and actuators

8. Typical Configuration • Sensor is generally installed either close to or flush with edge of first desired object • Sn refers to the nominal sensing distance Configuration of sensor http://www.automationdirect.com/static/specs/proxterms.pdf ECE5320 Mechatronics. Assignment#1 Survey on sensors and actuators

9. Major Specifications • Mounting area • Real sensing distance (90%-110% of Sn) • Material to be sensed ECE5320 Mechatronics. Assignment#1 Survey on sensors and actuators

10. Major Specifications (2) • Repeatability • Be aware of linearity, hysteresis, excitation voltage instability, and voltage offset • Switching frequency • How fast will the sensor sense the object, reset, and sense another ECE5320 Mechatronics. Assignment#1 Survey on sensors and actuators

11. Limitations • Sensors become inaccurate if the sensing distance is less than the nominal sensing distance ECE5320 Mechatronics. Assignment#1 Survey on sensors and actuators

12. Different Types • Inductive • Sense metallic material • Nominal sensing distance of about 10mm • Correction factors may need to be applied for different types of metals detected ECE5320 Mechatronics. Assignment#1 Survey on sensors and actuators

13. Different Types (2) • Capacitive • Sense wood, paper, liquids, cardboard, etc • Unaffected by dust or opaque containers • Generally can sense further distances ECE5320 Mechatronics. Assignment#1 Survey on sensors and actuators

14. Different Types (3) The sensor will be one of the following: • Shielded • Face of sensor may be mounted flush with metal • Unshielded • Face of sensor may not be mounted flush with metal • If mounted improperly, sensor would detect the metal surface it is on and not nearby surface ECE5320 Mechatronics. Assignment#1 Survey on sensors and actuators

15. Different Types (4) The sensor will be one of the following: • Normally Open (NO) • Sensor doesn’t pass power until object is detected • Generally proximity sensors are this type • Normally Closed (NP) • Sensor always passes power until object is detected ECE5320 Mechatronics. Assignment#1 Survey on sensors and actuators

16. Different Types (5) The sensor will be one of the following: • 2-wire • Allow for either NPN (sinking) or (sourcing) PNP outputs • 3-wire • Standard sensor (must choose either NPN or PNP) • 4-wire • Choose either NPN or PNP output • Allows for either NO or NC output ECE5320 Mechatronics. Assignment#1 Survey on sensors and actuators

17. Manufacturers • This is an incomplete list of manufacturers that sell proximity sensors • Omega • McMaster • Omron • Grainger ECE5320 Mechatronics. Assignment#1 Survey on sensors and actuators

18. Styles Cylindrical Proximity Sensor http://www.manufacturing.net/products/2011/06/2-wire-dc-inductive-proximity-sensor Rectangular Proximity Sensor http://www.omega.com/ppt/pptsc.asp?ref=E2K-F ECE5320 Mechatronics. Assignment#1 Survey on sensors and actuators

19. Cost • Inductive sensors can range in cost from $80 - $110 • Capacitive sensors can range in cost from $127 - $165 ECE5320 Mechatronics. Assignment#1 Survey on sensors and actuators

20. Cost (2) • Costs vary with size and sensing distance • Larger variation in sensing distance costs more • These costs don’t include mounting accessories ECE5320 Mechatronics. Assignment#1 Survey on sensors and actuators