P13027: Portable Ventilator

Team Leader: Megan OConnellMatt BurkellSteve DigerardoDavid HerdzikPaulina KlimkiewiczJake Leone

P13027: Portable VentilatorOverviewProject SummaryCustomer NeedsEngineering SpecsSystem Block DiagramFunctional DecompositionRisk AssessmentProposed RedesignProject ScopeProject Objective: Improve the current design of P13026Duration: 27 weeksMarket Release: 2015Budget: $1000Customer:Jeff GuttermanRoman PressFaculty Mentor:Edward HanzlikTeam:4 Mechanical Engineers2 Electrical Engineers

Customer NeedsCustomer Need #ImportanceDescriptionComments/StatusCN11Maintain PortabilityPortable based on digital electronics, preferably on microprocessor, minimize weight and sizeCN21Include Audio FeedbackGives non-visual, non-braille instructions/feedbackCN31Optimize Battery LifeOperates for minimum of 2 hours without rechargingCN41Replaceable BatteryBattery easily replacedCN51Minimize ExpensesParts cost < $1000CN61Display Relevant DataShow information that will be necessary for the customer to operate the ventillator on the front panelCN72Measure Oxygen LevelsAdd a pulse oximeterCN82Measure CO2 LevelsMeasure CO2 levels on expirationCN92Optimize for mass productionCN103Design SimilarlyThe design of an updated version of the PEV that remains "substantially equivalent" to the design which received FDA 510(k) approval to manufacture and marketCN113Record and Transfer DataRecord and transfer dataCN123Reduce size/weight(less than 18lbs)Importance: 3: Preference only 2: Nice to Have 1: Must HavesEngineering SpecificationsPortable Emergency VentilatorEngineering Specifications - Revision 1 - 03/19/13Specification NumberSourceFunctionSpecification (Metric)Unit of MeasureMarginal ValueIdeal ValueComments / StatusS1PRPSystemVolume ControlLiters0.2 -1.2 S2PRPSystemBreathing RateBPM, Breaths per Minute4 -15S3PRPSystemPick FlowLiter/Min15 - 60S4PRPSystemAir Assist Senitivitycm H200.5 0.5S5PRPSystemHigh Pressure Alarmcm H2010 - 70S6PRPSystemDC InputVolts6 - 16Due to battery, must be greater than 9VS7PRPSystemDC Internal BatteryVolts12S8PRPSystemElasped Time MeterHours0 - 8000S9PRPSystemPump LifeHours4500S10PRPSystemO2 / Air mixerO221% - 100 %S11PRPSystemSecondary Pressure Reliefcm H2075S12PRPSystemTimed Backup BPMS13PRPSystemWeightKg 8S14RobustnessDrop Heightmeter1

System Block DiagramFunctional Decomposition

Top Level Functions

Provide Airflow

Monitor Feedback

Communicate State

Manage Power

Risk AssessmentRisk ItemEffect CauseLikelihoodSeverityImportanceAction to Minimize RiskTech Concerns1Integration of hardware and software togethernon-workable prototypeusing devices from different companies that don't function together339plan and read specs on all technical components; test components compatibility2inputs do not match outputsfailing to meet FDA requirementsprograming and calibration errors133quality testing of design3battery integration in systemunderperforming; fire hazardbattery failure; not meeting engineering specs313check with experts on how to manage battery functionality4Durability failurecomponents breaking; failure of systemcomponents malfunctioning during usage236perform vibration testing; perform environmental testingSeverity Scale:1= Not Severe 2= Moderately Severe 3=Very SevereLikelihood Scale:1= Not Likely 2= Conceivable 3=Very LikelyImportance= likelihood x severityRisk ItemEffect CauseLikelihoodSeverityImportanceAction to Minimize RiskProject Concerns5Over budgetcannot build a working prototype that looks like visionnecessary parts more expensive than budget leaving not enough money for aesthetics 313perform cost analysis; utilize resourcefulness; properly plan so things can be done right the first time6uncoordinated team schedulelate completetion of deliverables; lack of team unityconflicting schedules and desired meeting times224constant communication; survey of wekkly available time7late delivery of partsmodification to design schedule; miss deadlineslack of planning; problems with vendors224order parts ahead of time; expedite when necessary8Remaining substantially equivalent with current designdesign that is not capable with FDA approvalchanging the current design drastically beyond the FDA approved design133make sure any major changes to design are validated with client9conflicts with customermore budget needed; change design schedulechange in market; change in design plans; change in prospective122team members should maintain open communication with client; relevant market research10product does not match consumer needsnot profitablenot meeting FDA requirments; not meeting trends133benchmarking research11team skillset doesn't match taskmisdistributed work loaduneven distribution of disciplines224maximize group communicationSeverity Scale:1= Not Severe 2= Moderately Severe 3=Very SevereLikelihood Scale:1= Not Likely 2= Conceivable 3=Very LikelyImportance= likelihood x severityFrom 13026 -> Our Foundation to Build OnUpdates:Electronic controls (decrease size/more options)Smaller pumpReliable and smaller battery (2+ hours)Device ergonomics and usability

Additions:Ability to monitor and record vitalsPulse oximeter feedbackSignaling alerts

Revision B- Proposed RedesignUpdate:Battery Size-> Reduce Size & keep same capacityReduce Circuit Board size-> Create custom board for all electrical connectsPhase motor driver to a transistorDisplay ErgonomicsOverall Size and shape of PEVInstruction manual

Additions:Visual Animated Display-> Moving VitalsMemory capabilitiesUSB extraction of DataCo2 Sensor as additional Feature to PEVOverload Condition due to Pump MalfunctionBatteries: Area for improvementDecrease weightSmaller sizeLower priceHigher power capacity

BatteriesTekkeonTenergy 11.1V Heavy DutyTenergy 11.1V LIPOPower Capacity58 Wh111 Wh61 WhDimensions17.4cm x 8.43cm x 2.26cm20.5cm x 7.3cm x 2.2cm14.8cm x 5.2cm x 2.3cmWeight452 grams726 grams333 gramsPrice$200 $108.75 $57.99 Custom PCB SolutionWe plan on using a custom mixed signal PCB solutionAdvantages: Reduce size and weightgreatly reduce production costsManufacturabilityFlexibilityDisadvantages: High development costsA lot of workSome risks involved

Size and WeightAll electronics will fit on one PCB turning a volume into an area that can fit on the side of the enclosure and take up very little space

CostsDevelopment costs will be high but production costs will be very low

ManufacturabilityHaving only one board will minimize assembly time since fewer connections are requiredConnections to be made:BatteryLCDDials/SwitchesPumpAir lines to sensors

FlexibilityWe can customize our design to work with a wider variety of productsThis will potentially reduce costs since we can choose the best and cheapest components

Example: LCD DisplaySelection of LCDs we can interface with is greatly increasedThis allow us to use a display like this 7 diagonal touchscreen LCD available for only $97

Risks of Custom PCBWe may have trouble figuring out how to interface with some of the new features, particularly the pulse oximeterIf there is a significant problem in the initial PCB ordered, another order will have to be made to fix it which will be just as expensive

Housing ModificationsSmaller components = smaller package

Housing ModificationsOld Physical Limits:15in long X 10in high X 7in deep

New Physical Limits:11in long X 6.75in high X 6.5 in deepHousing Modifications

Additional Developmental TestingVibration Testing- How will the PEV stand up to external vibration and drop conditions?I. Random Vibration Frequency Testing (From 0- 2kHz) - Understand Natural Frequency of System (Resonance) and address measures to avoid this state- Specs: TBDII. Drop Testing- Understand g-forces with respect to system mass and height to drop. Allow us to make judgment on component damage.Usability Testing on Major Display ComponentsI. Understand General Usability-> Imagine RIT surveying (designed with Marie and David)II. EMT intelligent Usability-> Survey EMT and medical practitionersImproving Ease of UseImproving User Interface

Providing Audio Feedback

Supplying medical staff with patient dataAudio FeedbackWe plan on providing the user with limited audio feedback to guide them through using the PEVSimple Commands that cover the basic functionsNot a step-by-step instruction manual

Advantages: Provides assistance in hectic environmentsCould provide untrained personnel with guidance

User InterfaceSmall Improvements to make the User Interface more user-friendly

Adding small sections of display above settings/mode knobs that correspond with the user-selected settings

LEDs to help guide user during operation

USB Data ExtractionBy implementing a USB connection on the custom board, data scripts will be able to be downloaded after using the device.Text scripts will be time-stampedID-ing patients with a patient #Recording important information such as vitals and/or air flow/compressions administeredCan be used by medical experts when needed for legal/health-related issues.

Mass Flow Analysis(Between Pump outlet and Ventilator outlet)Replacing Mass Flow Sensor with Venturi AnalysisAssume incompressible flow: Constant density

Venturi Analysis compared to mass Flow SensorCost:Honeywell AWM2300V Mass Flow Sensor = $107.82Freescale MPX12 series Differential Pressure Sensor = $8.61Number of Parts:Current design about 6 partsProposed design about 8 partsAdditional parts on the order of a few dollars (reducers)Size:Mass Flow Sensor = 1.24x1.2x0.61=0.91 in3Differential Pressure Sensor = 1.15x0.69x0.43=0.34 in3

High Pressure Safety ImprovementsAudio Alarm: Software triggered alarm if flow rate is out of bounds of pump inputsAudio Alarm: Secondary pressure sensor records high back pressureMechanical Relief Valve: Fail safe to release system pressure if pressure exceeds a predetermined level

Bench Marking High Pressure PrecautionsBoth AutoVent and CAREvent have double redundant ways to assure the patient never experiences too high of pressure

CO2 Disposable SensorBenchmarking Current Technologies: