Vacuum-enhanced zipping actuators for space robotics

Actuating robotic systems in space is challenging, particularly due to the constraints of operating in vacuum. Conventional electromagnetic actuators suffer from heat dissipation and lubrication issues, while electrostatic alternatives, such as dielectric elastomer actuators, remain limited by poor reliability and the lack of space-qualified materials. We present a new class of electrostatic actuators that exploit the dielectric properties of vacuum, turning them from a limitation into an enabling feature. The devices employ multilayer thin-film polymeric structures with dielectric and conductive layers enclosing vacuum gaps. Under electrical activation, these gaps deform freely, generating zipping-like motions that produce actuation. We demonstrate bellow- and rhomboid-shaped architectures capable of delivering millimeter-range strokes over a broad frequency bandwidth.,The proposed actuators are made from standard space-grade polymers and are stackable, power-dense, direct-drive, and show negligible heating in vacuum. These characteristics highlight their strong potential as efficient and reliable solutions for future space robotics.