ECE5320 Mechatronics Assignment#01: Literature Survey on Sensors and Actuators Topic: Linear Solenoids

1. ECE5320 MechatronicsAssignment#01: Literature Survey on Sensors and Actuators Topic: Linear Solenoids Prepared by: Jonathan Black Dept. of Electrical and Computer Engineering Utah State University T: (435)797-1000; F: (435)797-3054 (ECE Dept.) W: http:// 3/9/2007

2. Outline • Reference list • To probe further • Major applications • Basic working principle illustrated • A typical sample configuration in application (application notes) • Major specifications • Limitations • Neat applications of solenoids ECE5320 Mechatronics. Assignment#1 Survey on sensors and actuators

3. Reference list • Bishop, Chiu, et. al (2002) “The Mechatronics Handbook”, CRC Press LLC http://engnetbase.com/books/774/0066ch20.pd • K. Harmer, G.W. Jewel1 and D. Howe (2002) “Transient performance of a short-stroke linear solenoid actuator” IEE Proc.-Electr. Power Appl. Vol. 149, No. 5, September, pg 379-384 • The Solenoid Company http://www.thesolenoidcompany.com/medical_applications.php • Nipro Europe NV http://www.nipro-europe.com/hemodialysis_machines.asp • Parmeko http://www.parmeko.co.uk/html/applications.html • Samarins.com http://www.samarins.com/glossary/starter.html • http://www.pd.com/rww/plane.html • Richard Condon (2003) Industrial WaterWorld, PennWell Corporation http://ww.pennnet.com/Articles/Article_Display.cfm?Article_ID=190516&pc=gls • University of Surrey http://www.ee.surrey.ac.uk/Workshop/projects/solengine.html ECE5320 Mechatronics. Assignment#1 Survey on sensors and actuators

4. To explore further (survival pointers of web references etc) • Search with this key words like linear solenoid, using search engines like Google. The USU library has a great electrical data base under the topics of engineering and technology, use EIcompendex and engnetbase.com • Searching for costs and specifications it is useful to use industrial like globalspec.com ECE5320 Mechatronics. Assignment#1 Survey on sensors and actuators

5. Major applications • Linear solenoids are applicable to any situation that calls for linear action. • Automotive, solenoid in the starter motor that will engage the flywheel or transmission to start the vehicle. • Medical (dialysis machine). • Hydraulic and pneumatics, valves can be controlled with solenoids (sprinkler systems). • Aerospace industry, (fly by wire systems). ECE5320 Mechatronics. Assignment#1 Survey on sensors and actuators

6. Basic working principle Basic idea of a solenoid is to produce a electro-magnetic field. The electro-magnetic field will then produce a electromotive force (emf). The emf will give a force (typically a pull) to a magnetic material that will then move. Like in motors and other electromagnetic devices the moving magnetic material is typically ferrous (contains iron). Bishop, Chiu, et. al (ch 20, pg5) ECE5320 Mechatronics. Assignment#1 Survey on sensors and actuators

7. Basic working equations Where, B is the magnetic flux density, H is the magnetic field strength, μ0 is the permeability constant of the magnetic material, i is the current through the coils, F is the magnetic force, E is the electric potential. These equations help when thinking of the mechanics of a solenoid. Remember what is a vector and what is a scalar. ECE5320 Mechatronics. Assignment#1 Survey on sensors and actuators

8. Basic Working Configuration “The magnetic force generated is approximately proportional to the square of the applied current I and is inverse proportional to the square of the air gap δ, . . . “ Bishop, Chiu, et. al (Ch 20, p 6) A longer stroke of the solenoid with out sacrificing force can be accomplished by applying a bevel to the shaft and the frame. By doing so the stroke is increased but the air gap is still small. This has it’s limits see graph. Bishop, Chiu, et. al (ch 20, pg7) ECE5320 Mechatronics. Assignment#1 Survey on sensors and actuators

9. Major Specifications • Force, the diving push or pull (lbf, or Newtons). • Holding force, force that keeps shaft in position. • Operating temperature, the max and min temperatures the actuator can work. • Duty cycle, the amount of time the solenoid can be energized. Typically limited due to heat build up. • Response time, time to complete the stroke once coil is energized. • Power, needed to energize, typically in watts. ECE5320 Mechatronics. Assignment#1 Survey on sensors and actuators

10. Limitations • The greater the force required the shorter the stroke. • Duty cycles on high force solenoids is typically high. • If the application calls for continuous operation with a 100% duty cycle then the force is usually small. ECE5320 Mechatronics. Assignment#1 Survey on sensors and actuators

11. Modeling of a solenoid’s response The position of the armature or shaft of the solenoid can be measured and controlled. Harmor and associates have made models to predict the position of the shaft of the solenoid. This can be done very similarly with motors as well, but with angular position. Harmor, Jewell, and Howe (p380-381) ECE5320 Mechatronics. Assignment#1 Survey on sensors and actuators

12. Neat applications of solenoids Solenoids actuate diagrams or plungers that stop and control water and fluid flow. Richard Condon ECE5320 Mechatronics. Assignment#1 Survey on sensors and actuators

13. Neat applications of solenoids Make an engine with solenoids. It works similar to the gasoline. The linear motion of the expanding piston is replaced with a actuating solenoid. http://www.ee.surrey.ac.uk/Workshop/projects/solengine.html ECE5320 Mechatronics. Assignment#1 Survey on sensors and actuators

14. Neat applications of solenoids “Inside dialysis machines, two solenoids act in tandem to control differing levels of blood flow during the dialysis process. Plastic tubes carrying the blood are squeezed at a pre-determined rate to precise clamping requirements. Here the force stroke diagram defined by the application calls for the optimum use of magnetic flux technology.” http://www.thesolenoidcompany.com/medical_applications.php http://www.nipro-europe.com/hemodialysis_machines.asp ECE5320 Mechatronics. Assignment#1 Survey on sensors and actuators

15. Neat applications of solenoids Use of solenoids in forklifts actuate the valves for hydraulics. http://www.parmeko.co.uk/html/applications.html ECE5320 Mechatronics. Assignment#1 Survey on sensors and actuators

16. Neat applications of solenoids Starter motors in automobiles have solenoids that push the gear driven by the motor. Typically to engage the flywheel which starts the engine. http://www.samarins.com/glossary/starter.html ECE5320 Mechatronics. Assignment#1 Survey on sensors and actuators

17. Neat applications of solenoids Aircraft use solenoids to control fuel, hydraulic, and in this case smoke valves. “Fly by wire systems” use electrical signals not mechanical to control actuators. This helps cut down on weight. http://www.pd.com/rww/plane.html ECE5320 Mechatronics. Assignment#1 Survey on sensors and actuators

18. Conclusion • Solenoids work to the presence of a magnetic field that generates an electromotive force (emf). • Linear solenoids are applicable to most any situation that calls for linear motion. • Modeling of precise response of solenoids is possible and controllable. • One dominate limitation of solenoids is the duty cycle requirement. • For longer strokes, force is sacrificed and for greater force, stroke is sacrificed. ECE5320 Mechatronics. Assignment#1 Survey on sensors and actuators