The shortest route around the world

Through interactive exhibits, visitors can learn about the shortest path on the sphere, understand the principle of shortest path, and be able to diverge their thinking, as well as learn how to find the shortest path in other geometric shapes. The exhibit consists of an Earth model, interactive display screen, graphic board, and L-shaped booth. The Earth model is horizontally fixed on the exhibit stand, the graphic version is perpendicular to the exhibit stand, and the interactive display screen is embedded on the graphic version. The city name is displayed on the Earth model, with small holes attached to the name for visitors to insert plastic round rods and fix the starting point. A thin rope is tied to the round rod for measuring distance. Visitors choose any small hole on the Earth model, insert a plastic round rod as the starting point, and then straighten the string according to their own judgment to determine the endpoint of the shortest path from the city to Lishui. The route that matches the length of the rope will appear on the electronic map displayed on the screen. Visitors observe whether this path is a straight line or a curve.

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.

Map projection is the theory and method of using certain mathematical rules to transform the meridians and parallels of the Earth's surface into a plane. Due to the fact that the Earth is an irregular pear shaped sphere with a slightly wider equator and slightly flattened poles, its surface is an unpalatable curved surface. Therefore, any mathematical method used for this transformation will result in errors and deformations. To reduce errors according to different needs, various projection methods have been developed. Reference materials.