CONCEPT 3: SPRING BALL
This is a variation on a normal ball that incorporates the physical principles of motion due to expanding and compressing springs. Its main structure consists of three interlocking plastic rings. At each of the six interlocking points (which are indicated in the sketch of the toy), a spring is attached which has its other end attached to a chair in the center of the ball. On this chair is seated a little toy man who is free to move with the chair in any direction as dictated by the compression or expansion of the springs. To allow the toy to be more like a ball, the open space is covered with transparent plastic. This allows children to freely roll the ball while allowing them to watch the inner motion at all times.
This toy will be a little more expensive to construct than my other two toys. This greater cost will emerge due to the transparent plastic covering and due to the greater number of springs involved. This toy will be less durable than my other two toys since this one will definitely invite rougher play and will therefore be more prone to being tossed around thus possibly causing the plastic shell to crack. For the same reason, I would expect the toy to be targeted at children at least 6 years old so that they know not to touch cracked plastic in case the shell breaks.
Author: Rohit Rao (rur@andrew.cmu.edu)