Mass Flow Controller Mass Flow Controller SystemSystem

Client:Client:

Brad Hodgeman– Instrumentation Brad Hodgeman– Instrumentation Specialist, Comparative Specialist, Comparative

BiosciencesBiosciences

Advisor:Advisor:

Professor Emeritus John G. Professor Emeritus John G. WebsterWebster

Team Members:Team Members:

Aaron Huser, Cole Kreofsky, Dana Aaron Huser, Cole Kreofsky, Dana Nadler, Joe PoblockiNadler, Joe Poblocki

University of Wisconsin - MadisonUniversity of Wisconsin - MadisonBiomedical Engineering Design CoursesBiomedical Engineering Design CoursesINTELLECTUAL PROPERTY STATEMENTINTELLECTUAL PROPERTY STATEMENT

Problem MotivationProblem Motivation

Brad Hodgeman researches hypoxia Brad Hodgeman researches hypoxia and hyperoxia with rats at the and hyperoxia with rats at the Veterinary Science Building.Veterinary Science Building.

Current mass flow controllers are too Current mass flow controllers are too inaccurate, and the software is inaccurate, and the software is outdated.outdated.

There are undesirable, manual There are undesirable, manual aspects to protocol that need to be aspects to protocol that need to be eliminated.eliminated.

Problem StatementProblem Statement

The purpose of this project is to design The purpose of this project is to design a system that can create a reproducible a system that can create a reproducible and accurate hypoxic/hyperoxic and accurate hypoxic/hyperoxic environment with the capability of environment with the capability of oscillating between various oscillating between various concentrations of oxygen and nitrogen. concentrations of oxygen and nitrogen.

BackgroundBackground

Hypoxia and hyperoxia are atmospheric Hypoxia and hyperoxia are atmospheric conditions, where the oxygen level conditions, where the oxygen level deviates below or above normal (21%) deviates below or above normal (21%) concentration, respectively. concentration, respectively.

Hypoxia is a form of respiratory distress Hypoxia is a form of respiratory distress which induces certain physiological which induces certain physiological responses by the neuro-respiratory responses by the neuro-respiratory system. These responses have been system. These responses have been associated with SIDS, sleep disorders, associated with SIDS, sleep disorders, spinal cord injury, etc.spinal cord injury, etc.

Mass Flow ControllersMass Flow Controllers

Mass flow Mass flow controllers often controllers often aid in hypoxia aid in hypoxia research due to research due to their ability to alter their ability to alter Oxygen Oxygen concentrations to concentrations to desirable levels for desirable levels for testable testable consequences.consequences.

Current Gas Control SystemCurrent Gas Control System

Computer controlled Command Computer controlled Command Module (HyperTerminal Software)Module (HyperTerminal Software)

Four Analog Mass Flow ControllersFour Analog Mass Flow Controllers Two Manual Mass Flow ControllersTwo Manual Mass Flow Controllers Four ChambersFour Chambers

Design ConstraintsDesign Constraints

Variable gas concentrations and flow Variable gas concentrations and flow rates through a chamberrates through a chamber

Software with an easy to use Software with an easy to use interface and customizable featuresinterface and customizable features

Accurate mass flow controllers, Accurate mass flow controllers, digital or analogdigital or analog

Uniform tubing resistanceUniform tubing resistance Low sound levelLow sound level Capability for further expansionCapability for further expansion

Software DevelopmentSoftware Development

LabVIEWLabVIEW Graphical programming Graphical programming

environment made for environment made for engineers and scientistsengineers and scientists

Client has had previous Client has had previous experience using experience using DASYLab – a program DASYLab – a program similar to LabVIEWsimilar to LabVIEW

Ability to customize Ability to customize programs easily and programs easily and efficientlyefficiently

Variety of open source Variety of open source examples of current examples of current programs availableprograms available

Main Areas of FocusMain Areas of Focus

Mass Flow Controller ManufacturersMass Flow Controller Manufacturers Sierra Instruments – Sierra Instruments – Series 100 Smart-Trak™Series 100 Smart-Trak™ Advanced Energy – Advanced Energy – Aera® Mach OneAera® Mach One Mykrolis – Mykrolis – Intelliflow ™ IIIntelliflow ™ II

Interface typesInterface types AnalogAnalog DigitalDigital

DeviceNetDeviceNet RS485RS485 RS232RS232

Manufacturer MatrixManufacturer Matrix

Company AccuracyResponse

Time PriceCustomer

Service Flow Range Total

Advanced Energy +/- 0.5% (4)

<= 250 ms (5)

$1675.00 US (3) (3) 3 L/min (2) 17**

Mykrolis+/- 0.25% sp plus

0.35% fs (3) 1 sec (3)$1880.00

US (2) (3) 5 /min (5) 16

Sierra Instruments

+/- 0.7% of reading + 0.3% fs (2) 2 sec (2)

$1370.00 US (4) (4) 6 L/min (4) 16

Low=1 - 5=High**The Numbers

Don't Lie!

Digital vs. AnalogDigital vs. Analog

DigitalDigital Accuracy is a Accuracy is a

function of set function of set point (sp)point (sp)

Multiple gas Multiple gas calibration curvescalibration curves

Multiple set point Multiple set point calibrationcalibration

More cost efficientMore cost efficient

AnalogAnalog Accuracy is a Accuracy is a

function of full function of full scale (fs)scale (fs)

Manual individual Manual individual gas calibrations gas calibrations

Digital InterfaceDigital Interface

DeviceNetDeviceNet Most ExpensiveMost Expensive Too sophisticated for this Too sophisticated for this

systemsystem

RS232RS232 Least ExpensiveLeast Expensive

Ergonomically incompatibleErgonomically incompatible

RS485RS485 Moderately ExpensiveModerately Expensive Ability to daisy-chain Ability to daisy-chain

cablescables

System DesignSystem DesignLabVIEW software, RS485 interface and AE MFCsLabVIEW software, RS485 interface and AE MFCs

QuestionsQuestions

Any Questions?Any Questions?