Strange wheels

Through the interaction of non-circular wheels, understand the principle of fixed width curves in mathematics. The exhibit consists of tracks and non-circular wheels. One set consists of square wheels and curved tracks. When pushing the square wheels to roll on the curved tracks, it can be seen that the square wheels run smoothly because the side length of the square wheels is the same as the arc length of the tracks. The other group consists of Lelot triangle wheels and flat tracks. Place the board on top of the triangle wheels, push the board by hand, and drive the triangle wheels to roll on the flat track. It can be seen that the triangle wheels can also move smoothly, demonstrating the principle of fixed width curves in mathematics. The so-called fixed width curve refers to a shape clamped by two parallel lines. If the distance between these two parallel lines is equal in any direction, then this shape is called a fixed width curve. So the Lelot triangle wheel is a fixed width curve, which, although not circular, can still roll smoothly between the board and the flat track. Target group.

Interaction type: Interactive installation. The unit is designed for unsupervised public use: controls are recessed or shielded, moving parts are enclosed, and the interface is operable by a child of about six with no instruction. Where a screen is used, the language can be switched without changing the hardware, and the content can be replaced on site.

1. Fixed width curve: Circles and circular triangles have a characteristic that the distance between two parallel lines is always the same, regardless of the direction in which they are clamped. We refer to shapes with this property as "equal width curves" (or fixed width shapes). The original definition of an equal width curve was given by Franz Reuleaux, a German engineer in the 19th century: placing a curve graph between two parallel lines so that it is tangent to these two lines, no matter how the curve graph moves, as long as it is still within these two parallel lines, it will always be tangent to them. The distance between these two parallel lines is called the width of the equal width curve. 2. Luluox triangle: It is a special type of triangle that refers to a curved triangle formed by taking the vertex of a regular triangle as the center and its side length as the radius to form an arc. The triangle composed of these three arcs is called Luluox.