39-245
Rapid Design through
Virtual and Physical Prototyping
Carnegie Mellon University
Spring 2003
The concept behind this toy is very simple. Combining the idea that heat rises with the principle of why this is so, can easily explain why a hot air balloon floats off the ground with relative ease. Physically, when a gas is heated the molecules become more excited causing them to push farther and farther apart from one another, this increase of empty space between the separate molecules causes the hot air to become less dense than the air around it. As can be seen in many other physical models, such as a air bubble in water, the less dense material rises. Although a young child may not be able to understand this concept, he/she can view it happening by playing with this toy. The original sketch is included below.
The child would probably play with this toy with a friend or parent. The two could separate the tasks of either holding onto the balloon or heating the air inside. The heat in the balloon should not be sufficient enough to raise more than 10lbs from the ground. This toy will be fun to play with as, once the air in the balloon is heated, it will rise, and then slowly return to the earth as the air in the balloon returns to its original temperature.
The construction cost would be minimal, if a hair dryer was used, the material in which the balloon was manufactured out of could be any assortmant of lightweight fabric. I believe a "kite-material" would be effective. This should not cost more than $10 to manufacture the balloon with a string attached so that the child could hold onto it. The hair dryer would not have to be included. During the construction process, steps could be taken to increase the durability of the fabric used, otherwise, it will depend on how the child takes care of it. This hot air balloon should be relatively safe, just as safe as a kite.
