Cardboard Chairs:
The Plan:
After building the passive solar studio, we needed to fill the building with furniture. If the students were the master minds behind the studio, the students should decorate the building with their own creative ideas. That is why we built cardboard chairs. Some might say it is an art to construct these chairs with no adhesive materials. The single material is cardboard. In our case, a toddler of at least fifty pounds must be able to securely sit on the cardboard chair. Other rules including a ration of 64 square feet of cardboard, no use of glue or other binding mediums, and no cardboard thicker than a quarter inch. A stable structure is not the only important component. We also had to incorporate aesthetics, economy, and function. With an exhausting round of trial and error, we were rewarded with a solid cardboard chair.
The Plan:
After building the passive solar studio, we needed to fill the building with furniture. If the students were the master minds behind the studio, the students should decorate the building with their own creative ideas. That is why we built cardboard chairs. Some might say it is an art to construct these chairs with no adhesive materials. The single material is cardboard. In our case, a toddler of at least fifty pounds must be able to securely sit on the cardboard chair. Other rules including a ration of 64 square feet of cardboard, no use of glue or other binding mediums, and no cardboard thicker than a quarter inch. A stable structure is not the only important component. We also had to incorporate aesthetics, economy, and function. With an exhausting round of trial and error, we were rewarded with a solid cardboard chair.
Key Physics Concepts:
Tensile Strength - measures maximum amount of tensile strength, or pulling, an object can withstand without ripping. This is important to the structure of the chair during the initial sitting process. The force is distributed out as you sit in a chair. That outward motion can collapse the chair if the supports and shape are unable to endure the force.
Compressive Strength - measures the maximum amount of stress an object can sustain with a crushing load, or downward force. For obvious reasons, a chair can not crumple when you sit on it. Compressive strength is maintained with different sizes and shapes, but the vertical corrugation of the cardboard also served as a huge factor in the chair's compressive strength. When the corrugation was placed horizontal, the chair already was weak and vulnerable in the corrugation of the cardboard.
Compressive Strength - measures the maximum amount of stress an object can sustain with a crushing load, or downward force. For obvious reasons, a chair can not crumple when you sit on it. Compressive strength is maintained with different sizes and shapes, but the vertical corrugation of the cardboard also served as a huge factor in the chair's compressive strength. When the corrugation was placed horizontal, the chair already was weak and vulnerable in the corrugation of the cardboard.
Center of Gravity - the specific point in an object where the body's mass is concentrated. The center of gravity is vital in the stability of any chair. The higher the center of gravity, the more tolerant the object is to toppling. The lower the object, the more sturdy the object.
Toppling - when an objects center of gravity crosses over the object's base. The wider the base, the more likely the center of gravity will stay contained in the object. A tall skinny chair will topple at the touch of a pin. A short wide chair will serve as a durable cardboard chair.
Tensile and Compressive Strength Lab:
Some of the major concepts include tensile and compressive strength. We tested these principles by using Manila folder cut-outs to replace cardboard. First, our group designed different shapes to challenge the strength of pulling or tensile strength. Our shapes consisted of a square, a pentagon, and a trapezoid. Out of our options, the square worked the best. Because of its concrete shape, the tension was equally distributed among the square. The square, a name of equality, can withstand the spreading tension caused paper. Next, our group challenged the forces of compressive strength. We used Manila folder cylinders to hold the weight of a number of books, depending on how much each size cylinder could support. We began with a cylinder a foot in height and a half inch in diameter. This was proven to be the weakest contestant. The taller its center of gravity and the smaller the base, the least likely for the cylinder to stand stable. As we continued the experiment, we concluded that the cylinder with a height of four inches and a diameter of two inches worked the best. An object can not topple unless its body goes over its base. The wider the base, the more difficult for the object to exceed those boundaries. Not to forget that the closer the object's center of gravity is to the ground, the more likely for the object to stay sturdy. Our experiment provided great research to start building our cardboard chairs.
Some of the major concepts include tensile and compressive strength. We tested these principles by using Manila folder cut-outs to replace cardboard. First, our group designed different shapes to challenge the strength of pulling or tensile strength. Our shapes consisted of a square, a pentagon, and a trapezoid. Out of our options, the square worked the best. Because of its concrete shape, the tension was equally distributed among the square. The square, a name of equality, can withstand the spreading tension caused paper. Next, our group challenged the forces of compressive strength. We used Manila folder cylinders to hold the weight of a number of books, depending on how much each size cylinder could support. We began with a cylinder a foot in height and a half inch in diameter. This was proven to be the weakest contestant. The taller its center of gravity and the smaller the base, the least likely for the cylinder to stand stable. As we continued the experiment, we concluded that the cylinder with a height of four inches and a diameter of two inches worked the best. An object can not topple unless its body goes over its base. The wider the base, the more difficult for the object to exceed those boundaries. Not to forget that the closer the object's center of gravity is to the ground, the more likely for the object to stay sturdy. Our experiment provided great research to start building our cardboard chairs.
Construction:
Once we gained some perspective on the mechanics of cardboard chairs, we started building a scale model consisting of Manila folders. Initially, we planned to create a full sized chair to support a hundred fifty pounds. Our scale was one inch is equal to eight inches, therefore our scale model would have to support forty-three grams. This was the infamous "Parabola Chair." The scale model succeeded with flourishing colors but the actual full sized model failed miserably. Its ruins are now in the San Marin parking lot dumpster. We realized that the toddler chair would better suit our purpose since our evidence clearly exhibited that the wider the base and the shorter the center of gravity, the sturdier. It was time for Plan B: The Tot Lounger.
As a group, we congregated and looked back at the weaknesses of our "Parabola Chair." A very little amount of cardboard was contacting the ground, which couldn't support the tall chair's weight. The design was disproportional. Also, our design was overly complex. If your own project is not clear, it is almost certain not to work. Finally, we needed to position the cardboard with vertical, not the vulnerable horizontal, corrugation. With knowledge of our mistakes, we built the Tot Lounger. We only needed to cut three different shapes of cardboard and a wide base contacted the ground. The vertical corrugation also kept the cardboard durable. For more information, look at our new and improved cardboard chair.
Once we gained some perspective on the mechanics of cardboard chairs, we started building a scale model consisting of Manila folders. Initially, we planned to create a full sized chair to support a hundred fifty pounds. Our scale was one inch is equal to eight inches, therefore our scale model would have to support forty-three grams. This was the infamous "Parabola Chair." The scale model succeeded with flourishing colors but the actual full sized model failed miserably. Its ruins are now in the San Marin parking lot dumpster. We realized that the toddler chair would better suit our purpose since our evidence clearly exhibited that the wider the base and the shorter the center of gravity, the sturdier. It was time for Plan B: The Tot Lounger.
As a group, we congregated and looked back at the weaknesses of our "Parabola Chair." A very little amount of cardboard was contacting the ground, which couldn't support the tall chair's weight. The design was disproportional. Also, our design was overly complex. If your own project is not clear, it is almost certain not to work. Finally, we needed to position the cardboard with vertical, not the vulnerable horizontal, corrugation. With knowledge of our mistakes, we built the Tot Lounger. We only needed to cut three different shapes of cardboard and a wide base contacted the ground. The vertical corrugation also kept the cardboard durable. For more information, look at our new and improved cardboard chair.
Reflection:
The cardboard chairs were at the back of our minds amongst the commotion at the end of the school year. Honestly, we were worried about the completion of this project. Our first chair truly brought us down. The collapse of the chair was quite disheartening. It felt like in volleyball when someone blocks your hit and it goes down right on your own side of the court. We looked at pictures in books and online to create a new chair. We pulled bits and pieces from each source to build the Tot Lounger. This project taught me to use my research to build a successful product. Just winging it won't always work. By using the evidence we collected from the collapsed "Parabola Chair" and the Tensile and Compressive Strength Lab, we were able to create an efficient chair that served the purpose well. Notes aren't just busy work. They can always be helpful throughout projects in the rest of my school and career years.
Like I said before, being in a group with Cate and Ananya is great. We respect each other's opinions but also know when to resign each other's ideas. I could've been even more exasperated, but it was nice to know that we had each other's back. I can not imagine a better group than the one I've been working with for the past month and a half.
The cardboard chairs were at the back of our minds amongst the commotion at the end of the school year. Honestly, we were worried about the completion of this project. Our first chair truly brought us down. The collapse of the chair was quite disheartening. It felt like in volleyball when someone blocks your hit and it goes down right on your own side of the court. We looked at pictures in books and online to create a new chair. We pulled bits and pieces from each source to build the Tot Lounger. This project taught me to use my research to build a successful product. Just winging it won't always work. By using the evidence we collected from the collapsed "Parabola Chair" and the Tensile and Compressive Strength Lab, we were able to create an efficient chair that served the purpose well. Notes aren't just busy work. They can always be helpful throughout projects in the rest of my school and career years.
Like I said before, being in a group with Cate and Ananya is great. We respect each other's opinions but also know when to resign each other's ideas. I could've been even more exasperated, but it was nice to know that we had each other's back. I can not imagine a better group than the one I've been working with for the past month and a half.
THE TOT LOUNGER