Team #17Dynamic Muscle Recorder

Client: Dr. Enderle

Group Members:Michael PetrowiczJames PorteusFarrukh Rahman

Presentation Outline

Client and Objective Muscle Model Isometric and Isotonic Experiments LabView and Optimization Setup Cost Acknowledgements Questions

Client and Objective

Dr. John Enderle

Design and construct a measurement device to record muscle properties in junior level Biomeasurements lab

Specifications

Final product less than $300 LabView interface Record data from isometric and isotonic

muscle contractions

Muscle Model

Theoretical: 5 parameter model developed by Dr. Enderle (pictured right)

Animal Model: leopard frog gastrocnemius

Procedure Collect data from animal model Optimize theoretical model

parameters Reproduce isotonic experiment with

theoretical model

Isometric Contraction

Constructing the length/tension curve A plot of maximum

tension vs. length Multiple trials at different

fixed lengths Purpose: estimation of

K_se and K_lt, which are related by the slope, K’ 27 28 29 30 31 32 33 34

0

1

2

3

4

5

6

f(x) = 0.771428571428572 x − 19.8285714285714

Muscle Length (mm)M

ax F

orc

e(N

)

Implementation

Secure muscle at fixed length and stimulate

FlexiForce force sensitive resistor records force over time

Find max force at each length

Isotonic Contraction

Constructing the force/velocity curve A plot of maximum

shortening velocity vs. load

Multiple trials at different loads

Purpose: estimation of B1 and B2

0 0.5 1 1.5 2 2.5 3 3.50

10

20

30

40

50

60

70

80

90

100

Load (N)

Max

Vel

oci

ty (

mm

/s)

Implementation

Secure muscle to mass and stimulate

Phidgets Hall Effect sensor records position over time

Differentiate data and find max velocity at each load

LabView

Receives force and position signals Controls stimulator Displays data for viewing and writes to

file

Optimization

Matlab routine modified from that developed by Dr. Daniel Sierra

Uses force/velocity and length/tension data with an initial parameter guess to determine the optimum model parameters

Setup CostCost for prototype

Manufacturer Product Model   PriceTeckscan Flexiforce A201-25   $16.25Phidgets Hall Effect 1108   $10.75Home Science Tools Mass set

BS-WTHOOK   $34.95

  Aluminum Frame/Base     $0.00  Electrical Components     $0.00               total $61.95

Other Considerations Frog muscle Additional masses Electrical and aluminum for other setups

Acknowledgments

Dr. John Enderle, our sponsor Dr. Daniel Sierra, matlab optimization Dave Kaputa, LabView Serge and Peter, machine shop

Questions