Rover release mechanism Four releasable Frangibolts securely bind the robot to the lander deck. These are stiff and strong during flight, and they reliably, intentionally release after landing. The secure mechanical coupling between lander and rover is essential since guidance avionics reside in the rover, but require a high fidelity of dynamic coupling with the lander deck. The high stiffness is also essential to preclude flexure during launch and flight maneuvers. The bolts are pre-notched to establish precise, predictable breaking conditions. The intentional breaking is induced by heating a cylinder of TiNi memory metal that surrounds the notched bolt. The expanding memory metal tensions the bolt beyond its tensile limit. The bolt breaks, as predicted, at the notch.

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