User:Svinson00/Project2

Project Preference

 * 1) Bioengineering
 * 2) MakerBot PLA Material Characterization
 * 3) Wind Turbine

Problem Statement
Our group will characterizing PLA and its use in 3D printing. Upon completion of this project cycle, we will need to create a CDIO Implement Report.

Project Plan
Throughout the project cycle, out group will be testing different variations of PLA each week, including color, temperature, strength and fill direction. Determining the PLA's elastic modulus will determine how stiff the material is.

Week 1 Narrative
My task for the first week was to perform a 3-point bending test on a black rectangular beam of PLA. The beam's original dimensions had a length of 189 millimeters, a width of 9.87 millimeters, and a height of 5.06 millimeters (15 millimeters were subtracted from the length on each side to accommodate the triangular supports). I began the test by adding a 50 gram weight hanger onto the string at the center of the beam. I began adding 200 gram increments to the weight hanger, while stopping to mark its position along the beam. The string broke while adding 1100 grams (for a total of 1150 grams). I restarted the whole test to prevent error. After the test, I measured the distance between the base line and each deflection using a digital caliper. Next, I substituted each value into the equation of {FL^3}/{4wh^3δ} to find its modulus of elasticity.

Once Eavg had been calculated, I could use sample masses of 950 and 1350 grams to test how accurate the experimental value of Eavg is using the equation of δ = {FL^3}/{4wh^3E}

Group CDIO Report

Week 2 Narrative
Since the MakerBot was disabled during this week, we decided (along with advice from Professor Edelen) to replicate the previous trial 9 more times (for a total of ten trials) to eliminate bias from performing just one trial test. I continued using the black beam from last week which had the dimensions of 189 mm by 9.87 mm by 5.06 mm. I used the same procedure from last week; nothing changed except performing the test 9 more times. The equation of {FL^3}/{4wh^3δ} was used to find the modulus of elasticity.

Week 3 Narrative
My task for Week 3 was to collect data for a beam whose cross-section was length by height. The PLA beam had a length of 19 centimeters, a height of 5.05 centimeters and a width of 10.07 centimeters. A teammate had written a code for the group to use in MATLAB to help calculate the Modulus of Elasticity; I didn't have MATLAB to use at home. Instead, I generated a table of results in Microsoft Excel and used formulas to calculate the average of E in each trial, and the average in all 10 trials.

Week 4 Narrative
During weeks one through three, we focused on calculating the stiffness or the modulus of elasticity for different variations of PLA such as color and fill direction. For the last week, we tested the strength of PLA through a 2 point test. A hole was drilled at the edge of the beam so a weight hanger could be attached. The other side of the PLA beam was clamped to the table. We added weights of 200 grams until the beam was deformed permanently. Weight was increased again in increments of 200 grams until the beam snapped.