Traditional Culture Encyclopedia - Hotel accommodation - The movable clothes rack is triangular or quadrilateral.

The movable clothes rack is triangular or quadrilateral.

The clothes rack is triangular.

Because only triangles are stable and parallelograms are unstable, retractable doors are designed by using parallelogram instability, and parallelograms are unstable. According to this characteristic, people can design telescopic doors, elevators and other items in daily life, and according to the stability of the triangle, it has the characteristics of stability and compression resistance.