For this unit, Faster, in our STEAM class, Design and Engineering, we took our knowledge of simple machines and geometric shapes from Unit 1 and applied it to circles and movement. We learned about velocity, mass, acceleration, how to graph them, and how they can apply to wheels. We also learned about simple machines that use circles, such as the pulley and the wheel and axle. During this unit, we had many interesting Field Experiences, such as visiting Beyond Design, an industrial design firm, volunteering at Working Bikes, a partial charity, partial bike shop, and talking to an employee of Divvy Bikes, Chicago’s bike sharing network. For our Action project this unit, we had to design a bike for a specific persona, a made-up person who describes a common issue with a product. If you would like to learn more, you can see my partner, KM’s blog, here.
I learned that there is not much variation on bike frames and wheels. Almost all of the bikes have the familiar triangle shaped frame with upright handlebars and 2 tires on either end. Usually, new designs seemed to alter smaller portions of the bikes instead of larger changes. I also noticed that huge issues seemed to be with comfort and security. A common problem I have found with bikes is the comfort, especially with the seat shape and material. As I found in my interview with Sharon Holmes, an avid biker, “My seat is hard, and I can’t find one that’s comfortable enough, soft enough, or comfortable for long rides."
Persona and Goals
Our goal for this project was to design a bike for Peter, an 18-year-old resident of Hyde Park, Chicago. He uses his bike to get to school and back every day, and he takes the Lakefront Path, alongside the beach. He has a very long ride, about 11.5 miles, and it takes him more than an hour every morning. He has problems with his arms being in the same position for so long, and his legs get very tired after a long ride. He has also had his bike stolen from outside of his school before, so security is a concern. So, his main issues were with his comfort, efficiency, speed, and security.
Peter's Journey
Total Time= 1 hour and 10 minutes
Total Distance= 11.5 miles
Average Speed= 11 miles/hour
4.5 feet/second
Bike Dimensions and Calculations
Bike Height= 3 to 4 feet (adjustable)
Bike Length= 6 to 6.5 feet (adjustable)
Bike Width= 3 feet 4 inches
Back 2 wheels
Gear Ratio
Driven (wheel)- 48 cogs
Driver (pedal)- 26 cogs
48/26= 1.8/1 gear ratio
We decided to have a gear ratio where the pedal's gear is larger because this makes it easier to pedal, although a bit slower. We thought easier pedaling would be the priority for Peter because his journey is so long. With a low gear ratio, his legs will get less tired.
Potential v. Kinetic Energy
As the bike pedals, it will build up momentum and allow the rider to move without pedaling until friction will slow it down. Also as the bike is moving, it is using kinetic energy. Because Peter is riding along the lakefront trail, he will not have much potential energy, as the Lakefront is a very flat road. If there are any hills or bumps on the road, the bike will have the most potential energy at the very top of the hill.
Design Process
When designing this bike, we had a lot of things to keep in mind. Peter had many issues with his current bike, with comfort, speed, efficiency, storage, and getting tired easily. This made the design process very difficult for me and my partner. We had to come up with a bike that was comfortable, fast, efficient, had storage space, and allowed Peter to pedal for 11.5 miles without getting tired. This is why we decided to create a recumbent bike. A recumbent bike also called a lay-down bike, is typically used for professional bikers in races, not long distance rides. So, we had to modify the usual recumbent design to fit our needs. We added two sets of pedals, for the legs and the arms, to allow Peter to switch between them, giving his muscles a break, or use both at once, to be more efficient. We also added a water tank, as riding for too long without water can be very dangerous, especially for younger people. We also added a motor assist to the back wheels, that can be charged overnight, to make the long journey less tiring. The seat back is adjustable as to not make Peter's muscles stay in the exact same place for too long, and the cushion is made out of memory foam. The Blessed Express is perfect for a student like Peter, with its extra storage space, phone charger, and Bluetooth speaker. Saftey and security were also big issues, as his last bike was stolen from outside his school. That is why the bike folds up into a dolly. This way, Peter can roll the bike into his building easily to keep an eye on it. Because he takes the Lakefront path every morning, it can get pretty crowded, and with a recumbent bike, because they are low to the ground, they can be hard to see. We added two flags, both reflective and neon colored so he can be seen, and a telescoping and adjustable mirror so Peter can see behind and around him.
Conclusion
At first, my partner and I had a lot of difficulty coming up with a design that satisfied all of Peter's needs. It is hard to make a comfortable bike also fast, and an efficient one that also has storage. After doing some research about unusual bike shapes and frames, we decided on a unique version of the recumbent bike. I enjoyed getting to build the model and adding all of the details that weren't quite possible in a 2D sketch or graph. If I did this project again, I would ask for more time to get the basic design down, as I felt a little rushed to get to the modeling. Thank you for reading, I hope you enjoyed.
Works Cited
MDS, and Sharon Holmes. “Biker Interview.” 13 Oct. 2017.
“Recumbent Bike Shop .” Amlings Cycle, Amlings Cycle.
I learned that there is not much variation on bike frames and wheels. Almost all of the bikes have the familiar triangle shaped frame with upright handlebars and 2 tires on either end. Usually, new designs seemed to alter smaller portions of the bikes instead of larger changes. I also noticed that huge issues seemed to be with comfort and security. A common problem I have found with bikes is the comfort, especially with the seat shape and material. As I found in my interview with Sharon Holmes, an avid biker, “My seat is hard, and I can’t find one that’s comfortable enough, soft enough, or comfortable for long rides."
Persona and Goals
Our goal for this project was to design a bike for Peter, an 18-year-old resident of Hyde Park, Chicago. He uses his bike to get to school and back every day, and he takes the Lakefront Path, alongside the beach. He has a very long ride, about 11.5 miles, and it takes him more than an hour every morning. He has problems with his arms being in the same position for so long, and his legs get very tired after a long ride. He has also had his bike stolen from outside of his school before, so security is a concern. So, his main issues were with his comfort, efficiency, speed, and security.
What does our bike do better?
- Long distance bikes are almost always built for very experienced or professional riders. Ours is built for casual, ‘normal’ people.
- Our bike is specifically built for people who work or go to school. It is built to be relaxing before and after a long day of work.
- Our bike is perfectly designed for the lakefront and in Chicago, where no other bikes have been before.
- Peter's main issue was his long ride and staying comfortable throughout it. This is why we decided to create a recumbent, or lay-down bike. This allows him to seat with a comfortable seat with back support for his ride.
- Peter also got very tired pedaling for over an hour twice a day, so we added both hand and foot pedals so he can do both at once, or switch between them to give his muscles a rest. The back 2 wheels also have the option of motor-assistance, to relieve some of the force needed to pedal.
- Because Peter rides his bike to high school every day, he needs somewhere to store it while he is at school without it being stolen. This is why the bike folds into itself to make a dolly. This way, he can roll it easily into school with him so that it stays safe.
- As part of our class, we have:
- Interviewed an avid biker,
- Learned how to fix bikes at Working Bikes,
- Been taught by Amanda, an employee at Divvy Bikes, Chicago's Bike Sharing program,
- Learned how to build models with the Dyson Foundation,
- Researched unusual bikes and how they work,
- And we learned how to calculate Velocity, Kinetic Energy, Potential Energy, Momentum, Acceleration, and Gear Ratios
Peter's Journey
Total Time= 1 hour and 10 minutes
Total Distance= 11.5 miles
Average Speed= 11 miles/hour
4.5 feet/second
Bike Height= 3 to 4 feet (adjustable)
Bike Length= 6 to 6.5 feet (adjustable)
Bike Width= 3 feet 4 inches
Back 2 wheels
- Diameter- 30 inches
- Radius- 15 inches
- Circumference=πd=94 1/4 inches
- Diameter- 23 inches
- Radius- 11.5 inches
- Circumference=πd=72 1/4 inches
1 Mile- 63,360 inches
63,360 inches/94.25 inches= 672 rotations per mile(back wheels)
672*11.5= 7,728 rotations per journey
63,360 inches/74.25 inches= 853 rotations per miles(front wheel)
852*11.5= 9,798 rotations per journey
63,360 inches/94.25 inches= 672 rotations per mile(back wheels)
672*11.5= 7,728 rotations per journey
63,360 inches/74.25 inches= 853 rotations per miles(front wheel)
852*11.5= 9,798 rotations per journey
Bike Models
Drawing with Labels
Graphed Model
1/20 scale model
Drawing with Labels
 |
| Bike Labels, KM and MDS, 2017. |
Graphed Model
 |
|
1/20 scale model
 |
| Biking along the Lakefront Path, MDS and KM, 2017 |
 |
The Blessed Express, MDS, and KM, 2017. |
Gear Ratio
Driven (wheel)- 48 cogs
Driver (pedal)- 26 cogs
48/26= 1.8/1 gear ratio
We decided to have a gear ratio where the pedal's gear is larger because this makes it easier to pedal, although a bit slower. We thought easier pedaling would be the priority for Peter because his journey is so long. With a low gear ratio, his legs will get less tired.
Potential v. Kinetic Energy
As the bike pedals, it will build up momentum and allow the rider to move without pedaling until friction will slow it down. Also as the bike is moving, it is using kinetic energy. Because Peter is riding along the lakefront trail, he will not have much potential energy, as the Lakefront is a very flat road. If there are any hills or bumps on the road, the bike will have the most potential energy at the very top of the hill.
Design Process
When designing this bike, we had a lot of things to keep in mind. Peter had many issues with his current bike, with comfort, speed, efficiency, storage, and getting tired easily. This made the design process very difficult for me and my partner. We had to come up with a bike that was comfortable, fast, efficient, had storage space, and allowed Peter to pedal for 11.5 miles without getting tired. This is why we decided to create a recumbent bike. A recumbent bike also called a lay-down bike, is typically used for professional bikers in races, not long distance rides. So, we had to modify the usual recumbent design to fit our needs. We added two sets of pedals, for the legs and the arms, to allow Peter to switch between them, giving his muscles a break, or use both at once, to be more efficient. We also added a water tank, as riding for too long without water can be very dangerous, especially for younger people. We also added a motor assist to the back wheels, that can be charged overnight, to make the long journey less tiring. The seat back is adjustable as to not make Peter's muscles stay in the exact same place for too long, and the cushion is made out of memory foam. The Blessed Express is perfect for a student like Peter, with its extra storage space, phone charger, and Bluetooth speaker. Saftey and security were also big issues, as his last bike was stolen from outside his school. That is why the bike folds up into a dolly. This way, Peter can roll the bike into his building easily to keep an eye on it. Because he takes the Lakefront path every morning, it can get pretty crowded, and with a recumbent bike, because they are low to the ground, they can be hard to see. We added two flags, both reflective and neon colored so he can be seen, and a telescoping and adjustable mirror so Peter can see behind and around him.
Conclusion
At first, my partner and I had a lot of difficulty coming up with a design that satisfied all of Peter's needs. It is hard to make a comfortable bike also fast, and an efficient one that also has storage. After doing some research about unusual bike shapes and frames, we decided on a unique version of the recumbent bike. I enjoyed getting to build the model and adding all of the details that weren't quite possible in a 2D sketch or graph. If I did this project again, I would ask for more time to get the basic design down, as I felt a little rushed to get to the modeling. Thank you for reading, I hope you enjoyed.
Works Cited
MDS, and Sharon Holmes. “Biker Interview.” 13 Oct. 2017.
“Recumbent Bike Shop .” Amlings Cycle, Amlings Cycle.
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