Tension vs. relaxation
Two separate elements are inflexibly connected with each other by using adequate tension. If an arm is strongly flexed its separate parts, the upper arm and the forearm, cannot be moved against each other.
We took on this aspect and integrated it into a series of hinges. Two areas are connected in two places each and thereby linked horizontally.
If one of these connections is loosened it expands towards the opposite direction and forms an angle. This way a hinged joint is developed which is flexible in two directions.