Lin, MaohuaVatani, MortezaChoi, Jae-WonDilibal, SavaşEngeberg, Erik D.2024-06-132024-06-1320200924-42471873-306910.1016/j.sna.2020.1122212-s2.0-85089814718https://doi.org/10.1016/j.sna.2020.112221https://hdl.handle.net/11501/1221Design, sensing, and control of underwater gripping systems remain challenges for soft robotic manip-ulators. Our study investigates these critical issues by designing a shape memory alloy (SMA) actuation system for a soft robotic finger with a directly 3D-printed stretchable skin-like tactile sensor. SMA actuators were thermomechanically trained to assume a curved finger-like shape when Joule heated, and the flexible multi-layered tactile sensor was directly 3D-printed onto the surface of the fingertip. A nonlinear controller was developed to enable precise fingertip force control using feedback from the compliant tactile sensor. Underwater experiments were conducted using closed-loop force feedback from the directly 3D-printed tactile sensor with the SMA actuators, showing satisfactory force tracking ability. Furthermore, a 3D finite element model was developed to more deeply understand the shape memory thermal-fluidic-structural multi-physics simulation of the manipulator underwater. An application for human control via electromyogram (EMG) signals also demonstrated an intuitive way for a person to operate the submerged robotic finger. Together, these results suggested that the soft robotic finger could be used to carefully manipulate fragile objects underwater.eninfo:eu-repo/semantics/openAccessSoft RobotTactile SensorMulti-Physics SimulationShape Memory AlloyElectromyogramArticle34629752Q1315WOS:000588262900004Q1