Controlling Speed MechanicallyThe Original GovernorModern GovernorElectrical Speed ControlsWhy Use an Electronic Governor?Why Use a Mechanical Governor?Mechanical Governor ShortcomingsSimple MatLAB SimulationRelation to Our Senior Design ProjectSlide 10Governors…in Bikes?Maximum Air SpeedStability GraphQuestions?Controlling SpeedControlling SpeedMechanicallyMechanicallyEngr 315Engr 315Control SystemsControl SystemsCalvin CollegeCalvin College8 December 20048 December 2004Brian KaterbergBrian KaterbergAndy Vander MorenAndy Vander MorenThe Original GovernorThe Original GovernorJames Watt’sJames Watt’sFlyball GovernorFlyball GovernorUsed to prevent steam engines from overheating Used to prevent steam engines from overheating while responding to the applied loads.while responding to the applied loads.http://home.carolina.rr.com/microhydro/governors.htmlhttp://home.carolina.rr.com/microhydro/governors.htmlModern GovernorModern Governorhttp://home.carolina.rr.com/microhydro/governors.htmlhttp://home.carolina.rr.com/microhydro/governors.htmlElectrical Speed ControlsElectrical Speed ControlsTachometerTachometerAutomotive Cruise ControlAutomotive Cruise ControlAndy Wallner’s Presentation Andy Wallner’s Presentation YesterdayYesterdayWhy Use an Electronic Why Use an Electronic Governor?Governor?Allows for very precise governingAllows for very precise governingRequires very limited amount of moving Requires very limited amount of moving partspartsCan fit in small areasCan fit in small areasEasy to adjust for changes in applicationEasy to adjust for changes in applicationInterfaces easily with other controlling Interfaces easily with other controlling devicesdevicesWhy Use a Mechanical Why Use a Mechanical Governor?Governor?Could be less expensiveCould be less expensiveCan use in wide range of conditionsCan use in wide range of conditionsMarine ApplicationsMarine ApplicationsExtreme TemperaturesExtreme TemperaturesUsually easier to troubleshootUsually easier to troubleshootMore transparentMore transparentMechanical Governor Mechanical Governor ShortcomingsShortcomingsHave a delayed response time called Have a delayed response time called “droop” “droop” This delay in response time induces This delay in response time induces something called “hunting”something called “hunting”Can be thought of in terms of overshoot and Can be thought of in terms of overshoot and over/under dampingover/under dampingCan tune a mechanical system to minimize Can tune a mechanical system to minimize hunting using additional external mechanical hunting using additional external mechanical governorsgovernorsSimple MatLAB SimulationSimple MatLAB SimulationRelation to Our Senior Design Relation to Our Senior Design ProjectProjectWe are building a winnowing machine We are building a winnowing machine for use in Kenyafor use in KenyaNeed some sort of governing device to Need some sort of governing device to control the speed of our fancontrol the speed of our fanDevice must be simple, easy to use, Device must be simple, easy to use, and low costand low costKenyan’s background should be taken Kenyan’s background should be taken into account especially for repairsinto account especially for repairsNot much electrical experienceNot much electrical experienceBikes are major form of transportationBikes are major form of transportationGovernors…in Bikes?Governors…in Bikes?Di2 (Digitally Integrated Intelligence)Di2 (Digitally Integrated Intelligence)Automatic DerailleurAutomatic DerailleurThere Can Be!There Can Be!www.shimanocycling.comwww.shimanocycling.comMaximum Air SpeedMaximum Air SpeedSeed Characteristicsdiaseed.001m Volseed43diaseed22 mseed8 107 kgareaseeddiaseed22Force of Gravitygrav 9.81ms2 fgravmseedgravfgrav7.848 106 NForce of Air DragCd.5 air1.25kgm3fdragfgravAir Speed Calculationsvelairfdrag12Cdair areaseedvelair5.655msStability GraphStability Graph0 50 100 15000.20.40.60.8Stable ( )Unstable ( )degQuestions?Questions?MechanicalMechanicalGovernorGovernorA Governor A Governor on a Bikeon a
View Full Document