In this paper, the carbon dioxide (CO₂) plasma-assisted method was firstly developed for the preparation of dopamine coating polydimethylsiloxane (PDMS). The PDMS films were pre-treated by CO₂ plasma at the power of 30–60 W for 5–10 min and then modified by dopamine for 18 h. The results showed that many polar groups such as C-O bonds, C=O bonds, and O-C=O bonds were introduced into the surface of PDMS films, which successfully promoted the formation of poly(dopamine) coating. Finally, the results of contact angle measurements showed that the surface of the plasma-assisted dopamine grafted samples changed from 118° to 64°. The shearing adhesion strength increased from 2.22 N/cm² to 6.02 N/cm², almost three times that of the original sample. This method provides a successful strategy for obtaining good poly(dopamine) coating layers on PDMS with strong hydrophilicity and shearing adhesion, which can be widely applied in the fields of medical and adhesive materials.

The article presents a novel control strategy for cable-driven aerial manipulators (UAMs) aimed at enhancing impedance control during contact operations in complex environments. A fractional-order nonsingular terminal sliding mode control (FONTSMC) integrated with a disturbance observer (DOB) is proposed to improve the robustness and precision of the UAM under lumped disturbances. This developed approach utilizes the flexibility of fractional calculus, the finite-time stability of nonsingular terminal sliding mode, and the real-time disturbance estimation capabilities of the DOB to ensure smooth and compliant contact interactions. The effectiveness of the proposed control strategy is validated through comprehensive simulation studies, which demonstrate significant improvements in control performance, stability, and disturbance rejection when compared to traditional methods. The results indicate that the FONTSMC-DOB framework is highly suitable for complex aerial manipulation tasks, offering both theoretical and practical insights into the design of advanced control systems for UAMs.

Objective: To reduce hip joint muscles’ activation during walking with an active hip exoskeleton. Background: Few studies examine the optimal active assistance timing of the hip exoskeleton based on muscle activation characteristics. Methods: Sixteen gender-balanced healthy adults (mean age 28.8 years) performed four tasks (each over 20 min). Tasks were different in loading and assistance. Muscle activation was collected by surface electromyography. The collected oxygen consumption evaluated the performance of the proposed active assistance strategy. Results: Experimental results verified that lower muscle activation and metabolism could be achieved when the active assistance gait phase was 9–60% of the gait cycle than that of all-gait-cycle active assist. Conclusions: Regulating the exoskeleton’s active assistance timing according to muscles’ activation characteristics can improve functional assistance.

Although a lot of research has been carried out on the adhesion mechanism of gecko bristles, the research on the adhesion mechanism of materials inspired by gecko bristles is still unclear.