Fiber Waveguide Photoactuator for Long-Distance Polyarticular Manipulation

Fiber waveguide photoactuators (FWPAs) have shown great potential in space-relevant manipulation due to their electromagnetic interference immunity, compact and lightweight structure, and dexterous motion. Current FWPAs face severe limitations, including short manipulation distances, low light power programmability, low temperature shock tolerance, and limited articulation sites, resulting in low manipulation capacities in space applications. Herein, we first develop a high-performance FWPA that employs the bending loss characteristics of optical fibers for coupling internal light power with external thermal-sensitive materials. The FWPA features high optical coupling efficiency (absorptivity is ∼98.9%) and programmable light power supplies that enable a large bending angle of >200°, as well as exceptional kilometer-scale series polyarticular cascading manipulation along the optical fiber with low energy consumption (17 mW/°, 53 mW/mN), which fit the requirements of space-relevant manipulations. The proposed FWPA exhibits a high stability of deformation and force, as well as immunity to electromagnetic interference (performance variation <5.5%) and wide temperature shock (-196 to 175 °C). Nine fundamental designs of FWPAs and four distinct flexible FWPA cascading devices are developed by reconfiguring fiber arrangements and power distributions for different space applications, such as twisting, grasping, axial extension, and hinge actuation.