FDA / Future Iterations

Our device is a hybridization of a bicycle and a hematocrit centrifuge. This device has a far way to go before anyone would consider spending the money to undergo FDA approval. However I believe this prototype has given the project a clear foundation to build from, and with this foundation an FDA application won't alter much with further redesign.

In 2007 FDA reclassified blood centrifuges from class III to class II (special controls). This means that new blood centrifuges are now allowed to cite presently marketed devices which have receive approval to benefit their claim. This is the path out device would take. We would issue for 510(k) clearnece on the bases that own device performs the same function as pre-marketed hematocrit centrifuges. This would cut down on cost and speed up the process. And then hopefully be approved as a class II device.

Future implimentations as suggested by others have been discussed in previous blogs. However there were a few things I would've liked to implement if we had more time.

1. A housing for the centrifuge plate. I would like this part of the device to basically mimic that which is used in the lab. The only difference is that it should be power differently.

2. A digital read out to tell the user how fast he/she is going and maybe a time on the bike to let them know after 10 minutes.

3. An incentive. There is a cool exercise bike at the gym where you play a game while you workout. On the screen you are in a race. We could use a version of this where we just tell the user what spot they are in and how far ahead the next person is. A simplier idea is to make something light up to let them know they're doing it right.

4. Fill the seat and handlebars so you can see the centrifuge. If the casing is clear, the user would be able to tell exactly when the pack cell volume is seperated from the plasma.

Power point

I learned a great deal about Power Point through this project. I have always been a chalk talk person, I feel it is much more engaging. However, I was assigned by my group to put together to poster. After a half hour spent on Google searches to answer all my questions, I was ready to go. My first mistake was not setting the size of the poster before starting to add things to it, because after a while I realized I should have much more space then I allotted myself. This was bad because everything was now thrown out of dimension. I fixed this and moved on. Next I learned how to create arrows, change backrounds, etc... I was becoming a real pro. Look below to check out our poster.

But how fast is it?

After we had assembled the pieces and got the prototype working, we had to test how fast the centrifuge plate was moving. Originally we had calculated that the plate would move around 5,252 RPM. This number was found by assuming the average biker rides at a speed of 15 mph, with a bike wheel radius of 1.5 feet and a diameter of 1 inch for the plastic piece.

((1320 / pi) / .12) * 1.5 = 5 252.11312

These are the projects we had calculated, and now was the time to put our prototype to the test. We got the tachometer. We started pedaling. We touched it down. It read 5,000!! Success.

Lessons learned

Over the course of my engineering career, I have been reminded on more then one occasion of the importance of having a fresh pair of eyes review my work. Many times, I am so focused on what I think I need to fix that I don't see the simple answer. This was the case one of the nights I was working with Jess. As jess has stated in previous blogs, we had trouble with the alignment of the bike. First we couldn't remember how it looked before we took it off and secondly we were convinced that we could fix it with a little man power and tight screws. This was not the case, as ever time we got it going it would fall back out of alignment. The prototype was due in two days are we were scared. We needed some fresh eyes. Ryan, one of the mentors who was a great asset, took a quick look at the bike and realized a different peice was screwed in sideways. We realigned this part and everything else fell into alignment. I have two lessons to offer from this expereince.

1. Taking things apart is a great way to learn how they work, however take pictures of things before you take them apart.

2. Get a pair of fresh eyes to look at your work because they will always see something you overlooked. I guess it's human nature.

Off to Edgerton

After assessing the materials we had purchased, we realized what we thought we could accomplish by simply drilling was no longer the case. The plastic piece we hoped to attach to the rod which held the centrifuge which the belt wrapped around. After talking to Dennis, the D-lab machinist, we agreed the best bet would be to mill the steel out and use the lathe to keep to piece concentric. If this piece was not concentric then the centrifuge would not spin evenly. Thus I took the piece home and planned to stop by the Edgerton Center in the morning.

The Edgerton Center is a student workshop at MIT open daily. To gain access, all you need is to have lab experience though classes or through a workshop held by the center. I had previous experience so all I need to do was attend a safety lecture about the shop. Luckily I had been planning on working there this summer so I had easy access to a lathe. The milling was easy, however keeping the part still in the lathe gave my quite some trouble. The plastic was thin so I did not want to deform it be clamping down too hard, and at the same time the thin walls did not give me much to grab on to. In the end I figured it out with some help from Marc, the head of Edgerton. I took it back to D-lab and my calculations were correct. The rob fit perfectly through it.

The Final Event

Last Wednesday, we gave our final presentations to the class and our mentors. Emily and I walked the bike over to the presentation room. Everyone we passed gave us funny looks because we had what looked like a beat-up bike with a strange platform on top, complete with a toilet plunger. Our presentation basically discussed why we picked centrifuges as a project, our design process, our manufacturing process, and how we would take the Cyclo-Fuge to market. I was nervous, but I knew the presentation was going to be our biggest opportunity, besides the MIT Museum fair, to show off the Cyclo-Fuge and get people interested in it. Once our group got to the front of the room, my nervousness disappeared, and our presentation and demo went well.

Cyclo-Fuge is Great Because..

Our prototype was great/saved us a lot of time because it was modular, and because it was easily adjustable. If we wanted to play with a certain dimension or tweak something, most of the time we didn't have to machine or buy a new part. I think that's a sign of a good prototype--it can be played with, so the final design is as good and as appropriate as possible.