Wednesday, April 17, 2013

Week Three

We received our printed plastic model of a simple mouse femur.

We got the CT Scan of the mouse femur, and used ImageJ to view the it in 2D. We then imported the extracted file to ITK Snap in order to see the femur in 3D and tried to convert the file type to .stl so that we could import it to Creo.

By the end of class we were able to get a model together, but we had difficulties in sending it to the printer.  Our first files were too large to send, and then when we tried compressing the files, they came out corrupted and weren't able to print.

The initial CAD model we created
After much struggling with trying to simplify the model to decrease the file size, we had a breakthrough over the weekend when an additional feature of InVesalius was discovered that allowed the removal of extraneous parts.  Not only did this reduce the file size by almost half, but it also enabled us to eliminate things such as the knee cap which showed up in the CT scan, but are not studied in this project.  A walk-through will be posted sometime this week.
Unfortunately, we still have few ideas for how we might be able to edit the model, but that task will be tackled when it comes time.
The second healthy bone model we created.  This one lacks the extraneous portions, and the surface of the bone is smoother, simplifying the file and reducing the amount of waste that would be created during printing.

Wednesday, April 10, 2013

Week Two

We started lab section htis week with an overview of the math behind this project.  As a class, we derived the equations to relate stress, strain, modulus of the material, force applied, moment of inertia, and length.  We then created a simple Matlab script to plot displacement versus the estimated forces using inputted properties of the flexural test.  We took a trip up to the sixth floor of Bossone to see the Three Point Flexural Test machine, so that we could know the minimum length that can fit on the machine.  We rounded this out by creating a simple CREO model to test on the machine next week.


Our simple  model

Wednesday, April 3, 2013

Week One

           This week marked the start of our Engineering 103 Freshman Design Project. After getting some background information on what exactly we would be doing, we began by creating an outline for our design proposal. The most involved portion of today was setting up our blog. Below is the template we formatted for our design proposal:


INTRODUCTION:
  • Describe genetic mutations & properties/mechanisms of a bone
  • Explain how mutations affect bones
  • Objective = design bone out of weaker plastic that is still as strong/stiff as a healthy bone.
  • Tasks= create 3 bones, test bone strengths, use CREO
  • Challenges= figure out how to convert image files, how to apply math equations, and improve bone design and geometry.
  • Outcomes= a successful bone design made out of weakened plastic.

DELIVERABLES:
  • 3 bones:
    • one healthy, one mutated, and the design.

  • CREO drawings
  • stiffness/force equations
  • lab results and analysis of each modified bone design.

TECHNICAL ACTIVITIES:
3.1= Healthy Bone
3.1.1= CAD Model
3.1.2= Printing/Mechanism
3.2= Mutated Bone
3.2.1= CAD Model
3.2.2= Printing Mechanism
3.3= Designed Bone
3.3.1= CAD Model
3.3.2= Printing Mechanism

TIMELINE:
      Week
TASK
1
2
3
4
5
6
7
8
9
10
Set up blog
x
x








CAD design

x
x







Testing

x
x







Analyzing Data



x






Redesign




x





Testing





x
x



Analyze






x
x


Redesign







x


Final Proposal








x
x

FACILITIES:
  • Labs
  • CREO
  • Literature related to bones/mutations
  • 3D Printer
  • 3-Pt Bending Machine
  • CT Scan of bone

EXPERTISE:
  • CREO
  • Blogging
  • Ability to apply math
  • Knowledge of bones
  • Image J (skills on converting files)