In recent years, triboelectric nanogenerators (TENGs) have attracted increasing attention in sensing applications. Numerous studies have confirmed that TENG can be used as a sensor to monitor various environmental parameters. However, these works often concentrate solely on a single parameter. Here, we report a highly sensitive multiparameter triboelectric wave sensor (MTWS), comprising a sliding-mode TENG incorporated into flexible magnet layers, a foam ball buoy, and a connecting bar constrained within a linear bearing. A theoretical model, coupled with magnetic prestress, is formulated to predict the electro-mechano behavior of the sensor in response to actual test waves. The experimental results indicate that external magnetic prestress enhances sensor sensitivity, and the predicted wave height aligns well with the commercial sensor results. Based on the proficient energy transmutation advantage of sliding-mode TENG, a remarkable sensitivity of 33.627 μ A/(m/s) and a minimal resolution of 0.00137 m/s are reached in wave velocity monitoring. Importantly, the MTWS shows the ability to monitor wave height, wave speed, and wave period simultaneously. Our research establishes the substantial potential of MTWS as a multifaceted wave-sensing apparatus, rendering it highly adaptable for integration within marine wave surveillance systems.

Due to their high energy density and favorable load-to-weight ratio, shape-memory alloy (SMA) materials are ideal actuation sources for soft robots. However, the relatively long cooling time of SMA wires in soft bodies limits their response speed. In this study, we designed and fabricated a novel SMA artificial muscle. When active heat absorption was enabled through thermoelectric modules and the evaporation/dehydration effects of hydrogels, the cooling rate of the SMA wires increased significantly. Simulation and experimental results demonstrate that with the proposed heat-dissipation scheme, the cooling speed of the SMA wires improved notably, with a temperature drop of 9.6 °C within 4 s. Additionally, the designed agar/polyacrylamide hydrogel, which has a porous skeleton structure, achieved a water-absorption expansion rate that was 600% of the previous value. When a PVC elastic substrate was used, the bending angle of the SMA artificial muscle reached 71°, with minimal bending attenuation after 45 consecutive cyclic tests. A soft gripper composed of the novel SMA artificial muscles was capable of manipulating objects of various shapes. Overall, the combination of active and passive heat-dissipation strategies enabled the SMA artificial muscle to achieve excellent durability, rapid heat dissipation, and strong versatility, demonstrating its significant potential for various applications.

The existing human–computer interaction often presents problems such as bulky components, simple interaction methods, and poor universality. Here, we proposed a flexible electronic tattoo keyboard (FETK) system based on an electronic tattoo triboelectric nanogenerator (ET-TENG), which consists of an improved thermoplastic polyurethane (i-TPU) and conductive silver paste. The i-TPU is fabricated by adding tributyl citrate (TBC) and calcium carbonate (CaCO₃) powder to TPUs to improve its flexibility and wear resistance. Considering the portability in practical use, we have designed a signal acquisition circuit and several postprocessing programs to obtain and identify signals from human finger touch accurately and stably. Furthermore, we proposed a dual-mode/multichannel strategy to increase the number of channels and achieve one-to-one triggering of commonly used keyboard keys. Finally, we demonstrated the interactive process of using it as a keyboard to control computer output. It is worth mentioning that the FETK system we prepared can be used as a universal keyboard for plug-and-play portable use.