Final Week

Today was the day of our final presentation.  The final deliverable completed all of the objectives that we set out to achieve.  The presentation went very well too.

We would like to thank the following individuals for their assistance and contributions to our project:

Dr. Jennifer Atchison
Marjorie Austero
Dr. Caroline Schauer
The Drexel Engineering 103 Staff

We would also like to thank Drexel University for providing us the opportunity to participate in a hands-on engineering project.

Week 9

Figure 1: The final well plate design

This week, the final design of the well plate was completed.  In contrast to the previous design, in the final design the rod holders spaced out 1 mm more each.  Also, the bed that they polymer sat in was reduced from 12 mm x 11 mm to a 9 mm x 9 mm square.  Finally, the wire hole was enlarged so a banana jack could be incorporated into the final design.  The banana plug replaced the bare wire to charge the polymer, and it was a much safer option because there was less exposed metal with the banana plug as compared to the bare copper wire.  The well plate will be printed by the end of next week, and will be used in the final presentation of the project next Friday.

Week 8

Figure 1: Printed Well-Plate

Figure 2: Printed Well-Plate

Figure 3: Printed Well-Plate

Figure 4: Team Member Chris Sets Up Electrospinning Tests

Figure 5: Printed Well-Plate

Figure 6: Electrospinner with Well-Plate

Figure 7: Electrospinner in Action

During the past week, the group received the printed design of the well-plate. Figures 1-7 show different angles of the well plate and how it fits into the structure of the electrospinner. The group immediately realized that the well had a couple of problems. One was that the dimensions of the well were too large, and the second was that the support arms were too high, causing the well to be too far from the stringed electrospinning wheel. The group decided that a change from the original 11cm x 10cm to 9cm x 9cm. In order to do this, the support arms will be lengthened in order to keep its original positioning, but it will also be lowered by 1 cm to correct the second issue.

Additionally, the group tested some samples with the new well-plate to check its effectiveness. These samples and some previous samples will be viewed under a Scanning Electron Microscope (SEM) in the coming week.

Week 7

Figure 1: Test settings

Figure 2: Run 2

During the past week, the group finalized the design of the well-plate. Subsequently, the design was sent to the 3-D Printer to be physically created. The well-plate printing should be completed early in week 8, allowing the group to test the functionality of the design and see if it works as anticipated. In addition, the group conducted more sample tests of the electrospinner. 2 samples were collected and viewed under an optical microscope. Figure 1 shows the first sample, in which the electrospinner used a random assortment of settings in order to get a feel for the instruments used. Figure 2 demonstrates the second sample, in which the electrospinner used a 4% PEO solution at 23.8 degrees Celsius and at 41% humidity. The electrospinner was run for 20 minutes, using a fly height of 14 cm, the normal speed of the motor, and 14 kV of electricity.

During the lab section, the group spun more samples with the electrospinner at different settings.  In the coming week, the group hopes to view these samples under the optical microscope in order to see the effectiveness of each setting.

Week 6

Figure 1: Thinner Well Plate Design

Figure 2: Electrospinning Demonstration

During the past week, the group needed to make changes to specific design decisions and began trials for the new electrospinner. The design of the well-plate was determined to be in need of efficiency maximization. Some problems realized were that it was too thick and that the second wire hole was not necessary since the wire is not particularly malleable. It is in the process of being updated to cut out unnecessary materials. A PEO solution of 300 mL, 600,000 molecular weight and 5 weight % was obtained to electrospin. During lab, the group spun 3 samples, 1 at each geared motor speed. The set up included the use of a power supply, the polymer solution, and the new electrospinner. The power supply was kept at 13 kV, the electrospinner held a constant distance of 14 cm from the base to the aluminum foil sheet, and the electrospinner was run for 20 minutes in each trial. Figure 1 shows the new changes to the well-plate design, and Figure 2 shows a demonstration of the electrospinner.

Week 5

                       Figure 1: Team Member Chris Muhrer demonstrates the gearbox design

Figure 2: Well-Plate Design

Each gear speed was tested this week.  Figure 1 displays all of the speeds that the electrospinner achieved.  This week, the group worked on designing a well plate using Pro/ENGINEER. Figure 2 displays the well plate design as of week 5.  The group focused on making the well plate adjustable in height with the addition of protrutions that connected to the supporting rods of the electrospinner. Additionally, two holes were included in the design to prevent the copper wire from shifting during experimentation. Further tweaks were made to the gearbox, finalizing its design as well. In the coming weeks, the groups hopes to print the well-plate design with ABS plastic using a 3-D printer and begin to perform lab tests in order to determine the effectiveness of the design changes.

Week 4

Figure 1: Control Design of Electrospinner

Figure 1 displays the original Electrospinner design.

Figure 2: Motor w/ Gears

Figure 3: Alternate view of  the Motor w/ Gears

Figure 4: Another Alternative View of the Motor w/ Gears

Figure 2, 3 and 4 are all views of the motors with the gears attached to it.

Figure 5: Modified Electrospinner Base to Attach to Geared Motor



Figure 6: Top View of the Modified Electrospinner Base

Figure 5 and 6 are the front and top view of the base of the modified electrospinner.

Figure 7: Assembled Gearbox

Figure 7 is the fully assembled gearbox.

Figure 8: Assembled Gearbox Speed Variation 1

Figure 9: Assembled Gearbox Speed Variation 2

Figure 8 and 9 are the views of the gearbox variations.

In Week 4, several goals were achieved by the team. A working gearbox (Figure 7) was designed and completed, although slight improvements to it were continuously being worked upon.  The gearbox is capable of running three different speeds. Additionally, further testing of electrospinning was done in order to gain an understanding of how the process works and a new design of the well-plate was sketched in Pro/ENGINEER. The testing parameters for future tests became clear. In the coming week, the team hopes to begin testing the new design of the electrospinner and view the results under a microscope.

Weeks 1-3

Figure 1 is displays the original design of the electrospinner built by Jennifer Atchinson.

Figure 1: Jennifer Atchinson's Original Design

Figures 2 and 3 are some other views of the original design.

Figure 2: Original Design Front View

Figure 3: Original Design Side View

During the past 2 weeks, the team accomplished several tasks.  Primarily, the team brainstormed ideas about improving the initial design of the electro-spinner. Some improvements discussed included the development and incorporation of a gearbox for the motor and a secure container for the polymer and the wire which goes into the polymer. The gearbox should allow the team the ability to control the speed of the motor, while the container for the polymer and wire will fortify the electro-spinning mechanism and shield outsiders from the wire.  The team built a second electro-spinner in order to track our modifications to the initial design. Additionally, the team completed the design proposal as a group and created a weekly work schedule in order to achieve reasonable goals on time. Furthermore, the team designed the blog and have been steadily polishing its layout.