Bike Cellphone Charger

download Bike Cellphone Charger

of 23

  • date post

  • Category


  • view

  • download


Embed Size (px)


Bike Cellphone Charger. Chris Battaglia (ME) Ajeetesh Govrineni (EE) Kellen Warriner (IE). Project Summary and Background. Create a system that harvests human waste energy and converts it into electricity in order to charge a cell phone To be used in Haiti - PowerPoint PPT Presentation

Transcript of Bike Cellphone Charger

PowerPoint Presentation

Bike Cellphone ChargerChris Battaglia (ME)Ajeetesh Govrineni (EE)Kellen Warriner (IE)

1Project Summary and BackgroundCreate a system that harvests human waste energy and converts it into electricity in order to charge a cell phoneTo be used in HaitiCollect energy from riding a bicyclePrevious team designed a system (upper right) but proved expensive, unappealing, difficult to manufacture, etc.Includes generator and cell phone holderCurrent plan is to optimize old design and achieve better resultsUsing MITs design (lower right) as the standard to meet/exceed

2Customer NeedsMust be able to charge Nokia cell phones (250mA, 3.5V)Ability to charge Blackberries (750mA, 5V) desirable but not strictly necessaryDesign should be adaptable and fit a variety of bicycle framesEasy installation (little to no tool use)User feedback is important, user wants to see the phone chargingTotal material costs should be 750need to research blackberry needs, seems like 750 mA needed, what is a sustainable biking speed?CN1, CN5S4Maximum current outputtargetmA15001000came from previous team, not sure why this is max.CN1, CN2S5Uses standard connectorsyesNAnoyesi.e.. UsbCN3S6Range of bike tires accommodatedmaxcm40.6 - 71.1 (kids and adult bikes)60.6 -71.1 (adult bikes only)CN9S7People required to install the devicemin# of people21CN9S8Number of tools required to install the devicemin# of tools270CN14S25% of people rating the device as more aesthetically pleasing than the previous versionmax%>60>75CN15S26Reduced environmental impact (embodied energy) over previous device (estimated)max%>0%>10%not sure what value to put on this as it is not a main requirementCN15S27Reduced environmental impact (embodied energy) over MIT device (estimated)max%>0%>10%not sure what value to put on this as it is not a main requirement4Test Plan

5Project Risk AssessmentIDRisk ItemEffectCauseLikelihoodSeverityImportanceAction to Minimize RiskOwnerDescribe the risk brieflyWhat is the effect on any or all of the project deliverables if the cause actually happens?What are the possible cause(s) of this risk?L*SWhat action(s) will you take (and by when) to prevent, reduce the impact of, or transfer the risk of this occurring?Who is responsible for following through on mitigation?1Long lead time on partsMake the project latereal world scenario9981Order long lead parts at end of first quarterKellen2Running out of budgetUnable to complete projectmismanagement of team funds3927Completion of budget to manage costsKellen3Design MalfunctionsPush project schedule potentially making the project latePoor equipment or design3927Accurate analysis of working systemAJ and Chris4Poor Team DynamicsUnable to Complete quality team workReduce quality of team project199Communication and even distribution of tasksteam5Miss team deadlinesUnhappy client/Lower grade in coursePoor management of team time199Complete team project timelineteam6Team Scheduling ConflictsUnable to complete team work/discussionFlexibility of group members339Create fix schedules to meet every weekteam6Technical Risk AssessmentIDRisk ItemEffectCauseLikelihoodSeverityImportanceAction to Minimize RiskOwner10Generator Produces too much heatGenerator burns upGenerator spins too fast, Housing does not dissipate heat, or phone requires too much electric load for specified generator199End of generator shaft has correct size wheel to run at rated speedChris11Bike Charger damages phoneBurn the phone up or phone won't chargeCircuit design does not protect phone3927A voltage regulator is used to prevent the phone from receiving too much voltageAJ12Bread Board produces to much heat inside housingBread board malfunctionsEnclosed Housing does not dissipate heat9981Heat Transfer Analysis to determine heat sync requiredChris/AJ7Generator Housing DesignSame general design but with a few modificationsHousing is made of cut stock PVC pipeEnd caps are glued along the inner diameter of the PVC and are made of cut PlexiglasOpted for simplicity and low cost over complexity and utility (details in next slide)Not shown:Weather stripping around generator for cushioningSmall spring acting against generator inside the housingShaft for generator rod has twice the diameter in clearanceWill hopefully be enough to hold generator shaft against any bike wheel. May need adjustments.

8Generator Housing CAD Drawing

9Generator Housing Concept SelectionThe need to machine metal (even just drilling) made choices undesirableMost of the options seemed too flimsy or expensiveUltimately needed to step back and return to the simplest solution for this projectKept the wiggle shaft idea and made it internal

10Frame AttachmentNeeds to support 4+ times the housings weight under rough road conditions (-Prof. Lam)Lack of machining equipment in Haiti prompts a purchased pre-manufactured componentGenerator can be removed by hand later, but only with added cost (clamps, wing nuts, etc all more expensive)No sure way to determine which options (See below) would be best. Luckily options are easily interchangeable so we can experiment during testingWill be used both on the frame and the generator housingNo need to machine into the housingShouldnt need an arm to bridge the two, but one can be made from plastic if necessary

$2.00 - $2.50$2.50 - $2.75(Current Design)$0.75 - $1.50$0.10 - $0.50

11Circuit Board Housing DesignDecided to use a breadboard over PCBCostHeat generation is the biggest concern mechanicallyAnalyzed under very conservative conditions (no convection whatsoever)Nokia (3.75W) setup passes, Blackberry (10W) does not (see right)Current design is to place the breadboard in a separate housingMade of same materials as generator housingThermal testing may show that it can be safely placed in the generator housingGenerator shaft and any metal fasteners may dissipate enough heat

12Heat Transfer Calculations

13Phone Housing Design

Alternative Design to the purchased phone holderMore expensiveMore labor intensiveNot necessarily a bad thingCan be manufactured in HaitiMade out of cut sheet stock, glue, and one metal dowel14Phone Holder CAD Drawing

15Material SelectionMaterialCharacteristicsMetalWoodRubber AluminumPlasticDurability0-0+0Stability0--00Waterproofing0-+0+Corrosion Resistances00+++Longevity0-0++Availability/Different Sizes0000+Cost0++-+Processing Tools0++-+Sum (+)02436Sum (-)04120Sum (0)02332Sum Net Score0-2316Rank3524116ManufacturingGoal of project was to make device as cheap as possibleUse of mass produced productPVC pipe PlexiglassSteel rod and tubesTools Used:Handsaws, Cordless drill17ManufacturingUser AssembledCheaperCreate jobsSlow assembly timeLearning curveIncorrect assembly results in device not working

PreassemblyCosts more (labor in U.S.)Lower risk of assembly mistakes

18Circuit Selection

19Circuit Simulation

20Bill of MaterialsGenerator HousingPartPart SupplierPricePrice EachLeadtimeNotes2 in Stock PVCLowes$6.67 $0.10 Purchase in 10 foot Sections.25" PlexiglassLowes$25/sheet$0.18 2'X4' Sections (sheets)14 gauge wireTractor Supply$19.95 $0.02 SpoolRubber ConnectorsN/A$.10ea$0.20 Estimated, Unsure where to getLoctite Rubber CementLowes$4.67 $0.25 10.2 oz tube for caulk gunGeneratorOnline$2.50 $2.50 1 weekShipping costs reduce for large quantitiesCost Per Unit:$3.25 Phone HousingPartPart SupplierPricePrice EachLeadtimeNotes.125" PlexiglassLowes$25.50 $2.50 Purchase in 2'X4' SectionsLoctite Rubber CementLowes$4.67 $0.50 10.2 oz tube for caulk gun.125"X8" metal dowelLowes$6.08 $0.75 Rod is 6 feet longCost Per Unit:$3.75 21Bill of MaterialsPartManufacturerDistributerSerial NumberNamePart nameLevelRevisionMake/BuyNamePart #NamePart #Unit CostQuantityTotal Cost15 V Voltage RegulatorIC11ABuyNational SemiconductorLM2940Jameco8375051.3911.392USB A ConnectorSL3 and SL42ABuyAdam TechUSB-A-S-RAJameco20961810.4920.9832 Pin Connector MaleSL1 and SL22ABuyTE Connectivity440055-2DigikeyA100043-ND0.1620.32410 F CapacitorC1 and C33ABuyJameco ValueProR10/50Jameco298910.0920.1850.1 F CapacitorC23ABuyJameco ValueProR0.1/51Jameco21519700.0710.07615 ResistorR13ABuyYagoFMP200JR-52-15RDigikey15ZTR-ND0.0210.0272 Pin Connector Female2ABuyTE Connectivity440129-2DigikeyA100011-ND0.120.28Connector Pins3ABuyTE Connectivity1735801-1DigikeyA103922CT-ND0.140.4Total3.56PartManufacturerDistributerSerial NumberNamePart nameLevelRevisionMake/BuyNamePart #NamePart #Unit CostQuantityTotal Cost1Bread Board1ABuyJameco ValueProPCB-594Jameco20659411.95111.95222 AWG red wire2ABuyJameco ValuePro820-2*Jameco12579510.95110.95323 AWG black wire2ABuyJameco ValuePro820-0*Jameco12584010.95110.95424 AWG white wire2ABuyJameco ValuePro820-9*Jameco12583110.95110.95Total44.822Moving ForwardMSD II Project PlanAddress Issues in Detail Design ReviewPurchase components with long lead times