Play equipment that can be in a wave, spiral, open bed, hump, curved, a spiral combo, or custom?

A play equipment that you can move easily and without interruption backward and forward or from one side to the other, especially from a fixed point, or to cause something or someone to do this?

It requires a lot of arm strength in relation to total body mass, as well as much stronger hand grip.

A long plank balanced in the middle on a fixed support, on each end of which children sit and swing up and down by pushing the ground alternately with their feet.

It is a device consisting of a piece of taut, strong fabric stretched between a steel frame using many coiled springs.