Exact constraint for flexible bodies

A mechanism for constraining a flexible body comprising:

• the flexible body;
• a first pivot rocker, a second pivot rocker, and a third pivot rocker, each of which has a pivot connection to a base, an axis of each said first, second and third pivot rockers oriented parallel to a common plane;
• wherein the first pivot rocker is connected to the second pivot rocker with a first joint that constrain said first and second pivot rockers to move together in a direction normal to said common plane at a location of the pivot connection;
• the first pivot rocker is connected to the third pivot rocker with a second joint that constrain said first pivot rocker and said third pivot rocker to move together in the direction normal to said common plane at a location of the second joint connection,
• the second pivot rocker is connected to the flexible body at two locations, and the third pivot rocker is connected to the flexible body at another two locations.