The pattern shown above exhibits a very rich configuration space, allowing it to morph between several surfaces. However, the tradeoff is that the patterns such as this have a large amount of kinematic freedom; the above pattern has 84 degrees of freedom. This introduces the challenge of how to actuate the structure between each configuration.

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Multi-stability is a promising concept for simplifying actuation. By introducing springs throughout the structure (i.e., torsional springs on each fold), a design problem can be formulated to select spring parameters such that multiple target configurations are stable equilibrium configurations. If multiple configurations are stable, relatively simple actuation is required to snap the structure between stable configurations.

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This design problem can be further extended to include mechanical stops (i.e., angle restrictions on each fold). Specified configurations can be made effectively rigid due to contact in the stops which is maintained by the spring forces. Below is a prototype of a morphing phased-array antenna that has two effectively rigid configurations that correspond to spherical and flat surfaces.