11022 Transcutaneous Signal Transmission for LVAD

November 5 , 2010Yevgeniy Popovskiy, Vince Antonicelli, Craig

LaMendola , Chrystal Andreozzi

Determine if our Team is on Track New Ideas Meeting Customer Needs To Ensure our Proposed Solution is Feasible To Ensure that our Team has Developed that

Ideal Solution to the Problem at Hand

Detailed Design Review

Project Summary Customer Needs Engineering Specifications

Schedule Project 10022 Failures High Level Schematics Electrical Detailed Design Case Design Heat Transfer Analysis Cable Design Bill of Material Test Plan Questions, Concerns, Ideas Action Items Review

Detailed Design Review Agenda

The Left Ventricular Assist Device (LVAD) is a electro mechanical circulatory device designed to assist a patient with a failing heart. Typically, a patient will receive one for temporary use after a heart attack or major heat surgery.

Eliminate as many transcutaneous wires as possible running from the external battery and controller to the LVAD.

Project Background

The device must be reliable

The number of wires needs to be reduced

The cable diameter needs to be reduced

The cable needs to be more flexible

Meet FDA standards

Customer Needs and Engineering Specifications

THE SYSTEM NEEDS TO WORK!!!! Must Operate

Reliably for 6 hours Cable Size Reduced

to 3mm Improve Cable

Flexibility by 200% Internal Volume

must be less then 450 cm3

MSD I Schedule

MSD II Schedule

Failure What Happen? How we are going to fix it?

Chip Specification

Programming the Chip

Case was not Water tight

Wire was not flexible

Not enough Time for Debugging the System

Too Much Responsibility on One Member

Project 10022 Failures

Big Picture

“Big Black Box”

LVAD

Skin

ICs

ICs

Motor Controller

Amplifiers

External Case

Internal Case

Electronics Function

SKINThe Big

Black Box

MCC + MCTMotor Controller

Amplifiers

Sensors

PAAS=>PADS

3

1

2

SA

Current Schematic

Main

Controller+

A/D

+

Battery

Pump

Motor

Control

Skin

Linear Amplifier

BloodPump

SA

MCC MC

O

LADS LAOP

LAOG

MCP

SP

LAP

(Sensor Analog)

8 Wires

(Sensor Power)

2 Wires

2 Wires

(Mot. Cont. Out)

2 Wires

(Mot. Cont. Control)

(Linear Amplifier Output)

4 Wires4 Wires

2 Wires

(Mot. Cont. Pwr)

2 Wires

(Linear Amplifier Input)

(Linear Amplifier Output Return)

1 Wires

(Linear Amplifier Power)

Project 11022 Schematic

MCP

Main

Controller+

A/D

Skin

SA

MCC

MCO

PAAS

PAOP

PAP+MCP+SP

SP

Motor

Control

PWM

Gen.

BloodPump

MCC

NSD

Chip

+

Elect.

Chip

+

Elect.

(Sensor Analog)

8 Wires

(Mot. Cont. Control)

3 Wires

(New Signal Digital)

SA

(Sensor Analog)

8 Wires

(Sensor Power)

2 Wires

(Mot. Cont. Cont)

(Mot. Cont. Pwr)

2 Wires

(Mot. Cont. Out)

2 Wires

(PWM Analog Signal)

4 Wires

(PWM Mot Cont Sen Pwr)

2 Wires

(PWM Output)

8 Wires

PADS(PWM Signal)

4 Wires

PAP(PWM AMPLIFIER POWER)

Electronic Details

DAC

ADC

ADC

DN CNT

POR

COUNTERCOUNTER

SKININIT LOGIC

SA

PAAS

MCC

MCT

SA

PADS

MCC

MCT

CLR

INIT LOGICMUX

MUX

FLIP FLOP

External Internal1

3

2

Wire Diagram 1

Wire Diagram 2 (PADS)

Failure What Happen? How we are going to fix it?

Chip Specification • Wrong Number for Bandwidth and clock speed

• Chip did not fit in initial PCB

• Double check calculations• Plan on obtain all chips before

ordering breadboard

Programming the Chip • Underestimated the time required to program chip

• Using integrated circuit design, instead of a microcontroller

Case was not Water tight

Wire was not flexible

Not enough Time for Debugging the System

Too Much Responsibility on One Member

Project 10022 Failures

Internal Case *Design not finalized

Titanium 2 shielded compartments 3 piece design with 2 equally sized halves and shielding plate Main compartment to hold electronics provided by Customer Second smaller compartment to house our new electronics

• Main Compartment: 5.25” x 2.25” x 1.25”

• Second Compartment: 4.5” x 2.15” x 0.5”

• Outer Dimensions: 6.63” x 2.63” x 2.25”

External Case *Design not finalized

Aluminum One compartment Will accommodate 2” x 2” x 0.5”

board Outer Dim. 2.37” x 3.13” x 0.87”

Case Similarities

• Cord grips screw into case• Same 1/16” O-ring • Same square O-ring grooves• Sharp corners and edges eliminated• Adhesive board and cable mounts• Board will be grounded to case• Will be quoted by multiple local shops

Hardware on Cases

Cord Grips: Sealcon products Pressure tested

O-rings: Silicone 1/16” McMaster Additional sealing:

Loctite silicone sealant on O-ring seal Water tight thread tape on cord grip

threads, in addition to stock O-ring Screws: All Stainless Steel from

McMaster No lead time problems expected on

Hardware

Failure What Happen? How we are going to fix it?

Chip Specification • Wrong Number for Bandwidth and clock speed

• Chip did not fit in initial PCB

• Double check calculations• Plan on obtain all chips before

ordering breadboard

Programming the Chip • Underestimated the time required to program chip

• Using integrated circuit design, instead of a microcontroller

Case was not Water tight • Two cable exciting one round port

• Screw entering the case inside the O-ring seal

• ABS Material Not Waterproof

• More reliable materials• Corrected design flaws• Cord grips are guaranteed

Wire was not flexible

Not enough Time for Debugging the System

Too Much Responsibility on One Member

Project 10022 Failures

Intersection Point Temperature(oC)

Center 73.09 66.6955.0

9

Air-Titanium 53.91 47.5135.9

1

Titanium-Air 47.43 41.0329.4

3Tissue 43.00 36.60 25

Heat Transfer Analysis Internal Case

0 0.0020.0040.0060.008 0.01 0.0120.0140.0160.0180.00

10.00

20.00

30.00

40.00

50.00

60.00

70.00

80.00

Tissue

43 °C

36.6°C

25°C

Distance(m)

Tem

pera

ture

(oC

)

𝑞𝑥=(𝑇 ∞−𝑇 𝑖 )∑ 𝑅

Heat Transfer Analysis External Case

𝑞𝑥=(𝑇 ∞−𝑇 𝑖 )∑ 𝑅

0 0.002 0.004 0.006 0.008 0.01 0.012 0.014 0.016 0.01820.00

25.00

30.00

35.00

40.00

45.00

Tissue

43 °C 36.6°C 25°C

Distance(m)

Tem

pera

ture

(oC

)

Intersection Point Temperature(oC)

Center 43.33 36.93 25.33

Air-Aluminum 43.12 36.72 25.12

Aluminum-Air 43.05 36.65 25.05

Tissue 43.00 36.60 25.00

Reduce Cable Diameter Flexibility: the ability to bend a cable through

its full-range of required motion Bend Radius: is the minimum inside radius one

can bend a cable Stiffness: is the resistance of elastic body to

deformation by an applied force along a given degree of freedom

Cable

Cable

Cable Current Cable Designed Cable

Cable Diameter 8 mm 3 mm

Number of Wires

~40 8

Heat Shrink Tubing

Thickness 0.38 mm

36 Gage, 0 A

0.3 mm

22 Gage, 6

A1 mm

22 Gage, 6

A1 mm

Copper Shielding

3 mm

Make cable at RIT Custom cable Manufactures

Coast Wire & Plastic Tech., Inc. Calmont Wire & Cable Merit Cable Carroi’s Medical Cable American Biosurgical

Cable Choices

Failure What Happen? How we are going to fix it?

Chip Specification • Wrong Number for Bandwidth and clock speed

• Chip did not fit in initial PCB

• Double check calculations• Plan on obtain all chips before

ordering breadboard

Programming the Chip • Underestimated the time required to program chip

• Using integrated circuit design, instead of a microcontroller

Case was not Water tight • Two cable exciting one round port

• Screw entering the case inside the O-ring seal

• ABS Material Not Waterproof

• More reliable materials• Corrected design flaws• Cord grips are guaranteed

Wire was not flexible • Wire binding in many places • Quoting cable with professional harness engineering company

Not enough Time for Debugging the System

• Team ran out of time to debug the system

• Plan on ordering components and assemble early, giving us 3 weeks to debug.

Too Much Responsibility on One Member

• To much responsibility on one member of the team

• Design is completed in a manor that allow multiple people to complete the work independently

Project 10022 Failures

Bill of Material# System Part Name

Critical Characteristics/Functions Part Number Manufacturer

Cost per part

Quantity ordered

Shipping Cost

Total Cost

Lead Time

1Cable 22 Gage Wire

Power Wire, Continuous-Flex Miniature Wire 22 Awg, .052" OD, 600 VAC, Red 7071K623 McMASTER-CARR $1.86/ FT 25 FT ? 46.5

1 week

2Cable 36 Gage Wire

Signal Wire, 392 Degree F HI-Flex Miniature Wire 36 Awg, .012" OD, 30 VAC/VDC, Green 9487T112 McMASTER-CARR $0.54/ FT 25 FT ? 13.5

1 week

3Cable Copper sheilding

Copper Foil Tape W/Conductive Adhesive, 3/4" Wide X 6 Yards

Long 76555A713 McMASTER-CARR$14.39/roll 1 roll ? 14.39

1 week

4cable Cable Jacket

Flexible Polyolefin Heat-Shrink Tubing 1/8" ID Before, 1/16" ID After, 25' L, White   McMASTER-CARR

0.3756/FT 25 FT   9.39

1 week

5Cable Cable Cable between the body CWPT-Q10-0848Coast Wire and Plastic Tech., Inc. 13.52/ft 100 ft   1352

6 weeks

6Connector connectors lemo Connectors

 FGG.2K.326.CLAC80Z PEI-GENESIS 136.64 1  136.64

2 week

7Insulations Heat sink Paste

Zalman ZMSTG1 Super Thermal Grease Model:ZM-STG1 Catalog #: 55020842 55020842Radio Shack

$9.95 per container 1 n/a 9.951 Day

8Inner case Large cord grip   CD16MA-BR Sealcon   2      

9Inner case Small cord grip   CD12MR-BR Sealcon 3.94 2 7.46 (a) 24.18  

10Inner case Outer screws 10-32 SS cap screws   Mc Master Carr          

11Inner case Inner screws   90585A225 Mc Master Carr 5.52 1      

12Inner case Titanium Case   *******

Laurel Tool and Die   1      

13Outer Case Aluminum Case   *******

Laurel Tool and Die   1      

14Outer Case Outer screws 8-32 SS cap screws   Mc Master Carr          

15Outer Case Outer cover   9109k72 Mc Master Carr 21.48 1      

16Both Thread Tape   6802k11 Mc Master Carr 1.95 1      

17Both O ring   96505k21 Mc Master Carr 0.24 10      

Bill of Material

# System Part NameCritical Characteristics/Functions Part Number Manufacturer

Cost per part

Quantity ordered

Shipping Cost

Total Cost Lead Time

18Electric

alResistor 10M Keeps sig at a stable value inside 10mqbk-nd ? 5     1 WEEK

19Electric

alAnalog Mux Demux

Converts data from p to s and s to p

both   ? 4      

20Electric

alCounter (74163) Splits time for sigaling both 74HC4040 $0.63 4     1 WEEK

21Electric

alAdr Latch (74259) Memory inside 7400 Series ? 2      

22Electric

alNOR 4 Gate Chip IC to control counter to latch inside 7401 Series ? 2      

23Electric

alPower on Reset chip Provides Clr Signal outside     1      

24Electric

alTerminal Blocks holds wire both   ? 8      

25Electric

alPWB Holds IC components inside   ? 2      

26Electric

alPWB Holds IC components outside   ? 2      

27Electric

alA/D Converter Main part - converts signal inside

TLC2578IPWG4-ND

$15.95 2     1 WEEK

28Electric

alD/A Converter Main part - converts signal ouside TLV563 ? 2      

29Electric

alDC to DC 5v

converterConverts 15v to 5v both   ? 4      

30Electric

alDC to DC 3.3v

converterConverts 15v to 3.3v inside   ? 1      

31Electric

alClock clock (20Mhz) ouside   ? 1      

32Electric

alAdheasive back

stand offHolds the pwba down both 10971.00   18     1 WEEK

33Electric

al10pF Capacitors

Needed for decoupling bet. REFP & REFM on ADC

             

34Electric

al.1pF Capacitors

Needed for decoupling bet. REFP & REFM on ADC

             

35Electric

alParellel load 8 bit

shift regNeede to shift data to carry internal 74AC16652DLG4 $11.70 2     1 week

36Electric

al8 BIT SYNC BINUP DOWN COUNTER

  both 74HC40103PW,112

$1.19 2     1 WEEK

37Electric

alOR GATE   both 74AC32D $0.57 1     1WEEK

38Electric

alNOR 4 Gate Chip   INSIDE CD74AC02M96 $0.77 1     1WEEK

39Electric

alINVERTS   INSIDE

SN74AC240DWR$0.77 1     1WEEK

40Electric

alD FLIP FLOP   both

SN74AC74DR$0.55 1     1WEEK

41Electric

alAnalog Mux Demux   both

74HC4051PW,118$0.58 2     1WEEK

42Electric

alDual 4 bit binary   both

74HC4520DB,112$1.11 2     1WEEK

LVAD Simulation Signal Test Electronics Functionality Test Leak and Pressure Test Drop Test Heat Transfer Test Flexibility Testing

Bend Radius Stiffness

Test Plan

Before connecting to LVAD and Dr. Days Equipment we will be preforming a simulation by monitoring the signals coming in and out using Function Generator and Oscilloscope.

LVAD Simulation Signal Test

They System Must operate Continuously for 6 hours.

Test: 3 one hour test 3 one hour test in Water(dependent on

leak test) 1 six hour test

Electronics Functionality Test

Test fully assembled cases with no electronics inside O-rings will be installed with Loctite silicon

sealant Place cases in water 1 meter deep for 15

minutes Case will experience 10 kPa of pressure Cases will contain a test material to absorb

water Cases will be opened up to ensure success

Leak and Pressure Test

Test fully assembled cases with no electronics inside

Cases will be dropped from height of 1.5 meters Internal case will be dropped onto carpet to

protect surface from marking External case will be dropped onto concrete to

simulate worst case scenario We will inspect the cases to ensure full

structural integrity was maintained Secondary leak test

Drop Test

For feasibility reasons will be preforming the test in Water

Heat Transfer Test

0 0.002 0.004 0.006 0.008 0.01 0.012 0.014 0.016 0.0180.00

10.00

20.00

30.00

40.00

50.00

60.00

70.00

80.00

90.00

100.00Temperature

AirWaterTissue

Distance(m)

Tem

pera

ture

(oC

)

Flexibility Test: Bend Radius

Determine the Stiffness of the individual cables by apply 3 different applied Force.

Flexibility Test: Stiffness

C-Clamp

Cable

δ= Deflection

Applied Force

Spring Scale

RiskID Risk Item Effect Cause

Likelihood

Severity

Importance

Action to Minimize Risk Owner

1Electrics Produce too much heating

Failure of project

Not enough heat dispersion. Electronics heat production not

calculated correctly3 5 15

Research best heat sink options and apply to design.

Chrystal Andreozzi

2 Wire BreaksFailure of project

Too much stress and ware on the wire connects. Not enough analyzing of wire fatigue.

2 5 10Research best Wire fatigue

optionsChrystal

Andreozzi

3 Cass LeaksFailure of project

Case Design fails 2 3 6Research best case options and

leak testCraig

LaMendola

4 Parts arrive lateSchedule is

delayedUnreliable vendor, out of stock part 3 4 12

Constant communication with vendor, use reliable vendors, have

backup parts selectedTeam

5Longevity of component

Failure of project

Manufacture of components 3 3 9Look for quality components Make

Dr. Day are of failure possibility

Yevgeniy Popovskiy and

Vince Antonicelli

6Chips can’t handle

signal speedFailure of project

Poor IC family choice 3 3 9Make sure IC family can handle

the clock rate

Yevgeniy Popovskiy and

Vince Antonicelli

8Miswire of

componentsFailure of project

Rush thru work 1 3 3 Lay out on bread board first Yevgeniy

Popovskiy and Vince Antonicelli

9Electrical

component don’t fit in boxes

Failure of project

Poor design 2 3 6Communicate expected space

needsTeam

10

Unacceptably long time delay is

introduced by signal transmission

Poor LVAD function /

project failure

Poor research, important considerations overlooked,

calculations errors1 4 4

Calculate speed and tolerance needed, analyze alternatives

Yevgeniy Popovskiy and

Vince Antonicelli

11Design more

complicated than needed

Team does excess work,

excesses recourses

consumed

Poor consideration of design alternatives

3 2 6 Review each other’s workYevgeniy

Popovskiy and Vince Antonicelli

12 Project Failure Project FailureOur team does NOT fully understand the mistakes that team 10022 made

and we make the same mistake      Research to the best of our ability Team

?