The PEZ deployment force is provided by a constant force spring, which provides a constant force independent of extension length. The spring is mounted such that the motion of the spring re-coiling itself will deploy the Exo-Structure. The motion of the system is retarded by a rail-interference and pin-setting system that is best pictured: Figure 5.
The stowed state is maintained by a Frangibolt assembly. The Frangibolt is composed of a shape memory Ti-Ni alloy (SMA) encompassed by an insulated heating element. Once a voltage is applied and the actuator is heated the SMA expands supplying adequate tension to break a pre-notched TiAl6 bolt. This actuation is pictured in Figure 6 below.