Introduction: Bike Prototype
For Design and Engineering we had to produce a bike for a certain persona. Throughout the class we learned about how bikes operate, gears, laws of motion, etc. I also learned what my brother likes about bikes when I interviewed him. Through the interview I learned how my brother uses his bike, and I drew a diagram of his morning bike ride and what he liked and didn't like about his bike ride. I am proud of working with my partner and reinventing the wheel, which was one of the biggest challenges I have ever encountered. The purpose of this assignment was to produce a bike that would best suit the person we were making a bike for.
When researching about bikes we found that skinny hard tries are good for going fast and thick and softer tires don’t go really fast but there is more control for going over bumps. We also learned how electric bikes make it easier for elderly people to use a bike and that electric bikes are really expensive to buy. To understand other people’s thoughts on a bike I interviewed my brother and he said, "no matter how many people work on it there can never be the perfect bike.” What I got from this is that when it comes to bikes you have to take on one issue at a time, and make a bike to fix that issue. This is why I am trying to make a bike that will be both light and comfortable.
My user is a 13 year old girl who needs a bike to ride to school. Her ride to school is on a paved, bike path in a park and she stores her bike 5 steps underground. This is why she wants her bike to be comfortable, lightweight, and able to go up hills. The bike I produced is made of titanium to make it easy to carry up and downstairs. It has microfiber bands that are bound together to make a wheel that absorbs any discomfort. It will have a crescent shaped seat made of memory foam which makes it extra comfortable to not only sit on but ride on. The handlebars are two feet long and are made up of ergonomic material to allow easy grip and better stability.
Here are some statistics to show how the bike would work and what it provides. Christina lives three miles from school. She wants to take a nice scenic ride to school, so she probably goes about 12 miles per hour. Time = Distance / Speed Time = 3 miles / 12 mph = .25 hour x 60 minutes = 15 minutes to get to school Her average speed is 12 mph Meters per second = meters / seconds= (3 miles x 1,609 meters) / (15 minutes x 60 seconds) 4827 meters / 900 seconds = 5.36 meters per second My bike uses a wheel with a diameter of 25 inches Circumference = Pi x D = 3.14 x 25 = 78.5 inches There are 63,360 inches in a mile so 63,360 x 3 = 190,080 inches in my persona’s journey. Total inches / Circumference in wheel = number of rotations 190,080 inches in my journey / 78.5 inches = 2,421 rotations The scale conversion is every 1 ½ inch on the model is 25 inches in real life: (1 ½-25)
While we were keeping in mind the fact that the new bike has to be comfortable, lightweight, and ride-able on hills we encountered a couple of obstacles along the design process. The first obstacle we encountered was how to make the bike really lightweight. After we found the simplest of frames we put only what we needed on the bike. The wheels were the last part we looked at and figuring out how to make the wheel frame even simpler wasn't easy. I figured out this problem when I went to McDonald's and had to get multiple drinks, so I got the multiple cup holder that McDonald's carries. Once I finished passing out drinks I noticed that the spots where the cups go had a interesting design, the same design I was going to use to make a lightweight wheel frame. There was only one issue with the design though, it was already made and mass produced. So then I tackled an even bigger question, “how do I reinvent the wheel.” First I started to look at nature whether it be plants, animals, or minerals to see if I could find the next wheel; unfortunately this was a dead end. After all the brainstorming it finally hit me, literally the idea was flung at my head. My brother is applying for high school so he has been going to high school fairs and taking their brochures and other pieces of merchandise. One of which was a rubber bracelet that my brother was messing around with and flung it at my head. I picked up the band noticing its flexible properties and bending it in different positions, by doing this I wondered what if there was a bunch of these bands that were bound together in a circle. So I tested this theory out fictionally and having these act as wheels would not only make the bike comfortable, but make it lighter as well. There was one flaw with theses wheels and that was that you can’t turn without them folding over each other, so I decided to put covers on them and it fixed the issue. The second obstacle we encountered was how to make the bike comfortable, without adding any more weight than there needs to be. For the handles we went back to a previous presentation we watched on ergonomics, and we designed ergonomic handles that fit the human hand better. The second part to this problem was making a comfortable seat, but this was figured out differently. When I was watching T.V. a commercial came on for the Tempurpedic mattresses, and we tried to make a Tempurpedic seat for the bike.
If I won a laser cutter with this project the first thing I would do is bask in the glory for a minute or two and then immediately call my STEAM teachers saying that our school finally has a laser cutter. For quite a while my school has been building a new maker lab and we have been trying to find a laser cutter to put in this new lab. The labs purpose is to serve our school's students and help them to better understand the connection between what they are learning and the outside world. Having this laser printer we could teach students new skills to better their and the world's future. We already are having a class that is dealing with different CNC cutters and we have talked about a laser cutter, but we don't have the budget to buy a laser cutter. Here is the link to my school's website, were you can see for yourself what our mission is and what we offer. I hope that you understand our need for this fantastic tool and we would be honored to have one. Thank you for looking at my project, which wouldn't be possible without the resources of my school.