Cheetah Flex Foot: Diagram

Analysis:
Important Components of Flex Foot
- Carbon fiber material
lightweight
flexible
strong
- Artificial Socket
vertical shock absorber
determines ability to control actions of limb adn amputee's comfort
connected by an inverted pyramid shaped fitting - allows for angular change
- Leg (Calf Shank)
fitted with elastic springs - convert gravitational energy to kinetic energy
largest component of the flex foot
vertical shock pylon - reduces impact to residual limb
- Heel/Foot
fitted with elastic springs - convert gravitational energy to kinetic energy
active tibial progression - forces at heel are translated to linear motion
Carbon X active heel - stores energy during loading responses
energy vector optimization - controls how ground reaction forces are transferred
converts ground reaction forces to kinetic energy.

Springs - responsable for propelling the body forward (similar to a tendon)
converts weight into energy
Body Weight - the matter transferred throughout the flex foot system

The Advancement in Protheses

Technology related to the advancement in prosthetics has exponentially grown in the past years. Evolving from the first prosthetic made, the wooden peg, many new models have been designed that are much more efficient and allow the amputee greater mobility. Prior to the demand in research towards the dynamics in prostheses, those that had lost a limb were confined to limited movements and physical activity was very restricted. Through the success of Oscar Pistorious, the bilateral amputee track and field athlete, it has proven that technology has expanded in such a way that the new models of prostheses now give amputees a mechanical advantage over able bodied athletes. I believe that technology will continue to develop to a point where people merged with machines will become more efficient in every way possible in comparison to naturally made humans. A leap in research has recently been made in the field of bionics. Bionics are able to restore impaired body parts with mechanical devises that are neurologically controlled. This technology is not limited within prostheses, but can be adapted to restore a degree of any lost function. Although scientist are still perfecting this innovative idea, it is apparent that sometime within the next years people will have the ability to control artificial limbs with their brain. This creates a narrower gab between the mobile abilities of amputees in comparison to regular in tact limbed individuals. Technology plays such an important role in our lives today and it makes a person wonder where it will lead us in the future. Will an entire army of robots be constructed that become more efficient that current soldiers in war? How far will the government let scientist delve into applied science mixed in with human nature?

The Cheetah Flex Foot

I was first called attention to this topic of prosthesis technology during the 2008 Olympics in Beijing, China. Because I love watching sports and especially have an interest in track and field, this particular event involving advanced prosthetic legs caught my attention immediately. An amputee sprinter, Oscar Pistorius, was banned by the International Association of Athletics Federations (IAAF)from participating in sanctioned competitions, including the Olympics and World Championships. The IAAF stated that Pristorious's high performance, J shaped, prosthetic leg, the Cheetah Flex Foot, gave him an advantage of able bodied runners. A team of experts and biomechanics then ran experiments on the South African athlete in order to provide statistical proof for the case against of Pristorius vs. the IAAF. The scientific team compared Oscar Pristorius against track athletes with intact limbs to evaluate his energy cost of running, fatigue resistance and sprinting mechanics. All of the following were indeed similar to intact limb athletes except the sprinting mechanics which were markedly dissimilar. At top speed Pristorious exerts considerably less force against the ground in relation to his body weight and he spends 34% less time in the air. In addition he takes 21% less time to reposition his legs between steps and therefore is able to cycle faster. In summary, the results proved that Prisotrious did have an advantage over able bodied athletes and it was the correct decision to ban him from participation.

Locust Walk: The Aorta

Locust Walk may be described as the main artery within campus. It is therefore appropriate to compare Locust to the aorta, the major artery of the human body. The aorta is the largest artery in the body and is responsible for distributing oxygen to all other arteries. The main purpose of the walk is to allocate Penn students and other people of the city to their destination. Just as other arteries branch off of the aorta, multiple paths exetenf rom Locust and are used to distribute students amoung other parts of campus. Similar to these arteries, the other various paths are smaller in size, both length and width. Locust walk is composed of small units of bricks. Together these bricks provide the strength and support of the entire structure. The size of the brick is relative to the size of cells of the aorta. The aorta is made of of numerous cells that work together to make up the structure as a whole.

Analyzing Locust Walk

One of the purposes of the project was to analyze the structure and break it down to three different levels. Quantitatively, Locust walk runs from 34th - 38th street (4 blocks). I broke the length scales down to length, width, and size of the brick which compose the walk.
- Length: The average block of Philadelphia is about 150 meters and therefore locust
runs to about 600 meters in length
- Width: Locust Walk is about 644 cm long
- Brick Size: Locust walk is made up of bricks and within the brick pavement lies a
a design composed of smaller stones. The brick size is 190mm x 90.5mm
while the stone is 100mm x 100mm
The three length scales are very appropriate to the function of Locust Walk. Locust Walk is long enough to extend through the major parts of campus. It is unavoidable to pass through Locust Walk when travelling from the north side of campus to the south side. The main application of the walk is to transport students across campus. Therefore its width is suitable to hold a large portion of the student body however is not useful for holding cars or big motor vehicles. The walk is big enough for the people who travel on it, however it is not too big to interfere with other important parts of campus such as class buildings, sports facilities and various aspects of nature. The size of the brick also fits the function of the structure. The brick provides smooth yet sturdy support for the thousands that walk upon its path. It is fitting that multiple bricks are used so that all the force is not upon one giant rock bed. The size of the brick also make it easier to repair damages to Locust Walk. It is not as costly to rebuild a small section of individual bricks rather than try to replace a large piece of concrete

Penn's Campus

One of the reasons why I chose to attend Penn rather than any other college is because of Penn's beautiful urban campus. I remember walking through the university on my first visit and looking around at all of the fascinating architecture and appealing structures located throughout campus. One of the most aesthetically pleasing structures of this university is located right in the center of everything, Locust Walk. Out of all of my college visits, the thing I remember most is wandering down Locust and just taking in all it has to offer. It was a crazy experience. I really didn't even feel like I was in the middle of Philadelphia anymore and the ambiance seemed so alive with old customs and spirit that I wouldn't have been surprised if Ben Franlkin himself walked out of one of the buildings. This is why I chose Locust Walk for the topic of this project. It had such an important impact on me when I was just getting a feel for each different university and it still remains a striking appearance even though I walk along it almost every day. Discovering this structure wasn't really a matter of discovering like many people use the term. Locust Walk is not difficult to find. I'm sure every one on campus knows where it is and where it leads. Though I believe it is important to discover its impact upon Penn and the students that go here. I think Locust Walk, lying in the heart of campus, really unifies all of Penn and brings the entire student body together. It is easy to see that it is the center of all student activity, whether it is used for socializing, handing out flyers, advertizing a product, or simply to get to class.

Evidence vs. Wishful Thinking

Researching this topic proved to be pretty difficult. There was only limited information on how technology is able to reduce health care cost. Also, many of the sites and references available did not seem like a reliable source. I obviously was unable to think of ten ways that technology could aid in this problem, however I did zero in on a few good ideas and provided significant evidence in how to go about executing these technological advances in order to reduce the errors in health care systems. I don't believe that many of the references vested in personal interest in making the claims, but rather provided suggestions for other sources through extensive research to help solve the issue. This includes recognizing and analyzing the rate of medical administration errors that occur in a hospital and how it deters patient recovery; therefore increasing overall health care cost for others. Most of the references I used in order to verify the role of technology were more than just wishful thinking. However that does not mean that there were not numerous sites with only wishful outlooks out on the web.