Dandelion seeds can stably diffuse owing to the dominant drag rather than the lift-based mechanism of the streamlined leaves of the plant, where this is known to favor their long-distance dispersal with the steady vortex attached. However, the generation mechanism of the vortex and the aerodynamic force exerted on the seeds through multiple filaments remain unknown. Clarifying these subjects may help realize the optimal performance of porous structures under different flight conditions. This study conducts numerical simulations to illuminate the influence of gaps and the Reynolds number (Re) on the wake structures and consequent drag force of dandelion seeds. We fabricate the seeds into circular disks composed of evenly distributed square cylinders placed in a vertical flow field with Re of 100 and 400, with the porosity of the pappus (ε) ranging from 0.887 to 0.964. We explain the geometric properties of the attached, steady vortex rings and clarify their generation mechanism, i.e., the base bleed and convection effects competed with vorticity generation, based on which the gaps are confirmed to delay chaotic vortices from occurring compared with the solid case. The weakened leeward pressure is critical for the increase in the drag coefficient to reach the peak level. The enhanced drag coefficient is several times higher than that in the solid case, endowing the seeds with a high loading capacity, and the porosity corresponding to its peak is beneficial for the structural design. These conclusions provide positive insights into the design of ventilated aircrafts with optimal long-distance dispersal performance.

In order to solve the inevitable instability problem of dandelion-like unpowered aircraft, transient simulations are carried out for the transition to turbulence of the wake from stable to unstable stage under different Reynolds numbers, and the vortex mode characteristics presented by the vortex structure as the Reynolds number increases are identified. Furthermore, by monitoring the velocity and lift and drag coefficients at different positions in dandelion flow field, the spectral characteristics of flow velocity and aerodynamic coefficients in the turbulent phase triggered by extreme aerodynamic environment are revealed. Compared with solid disk, it is found that the bandgap structure is more conducive to expanding the stable flight threshold of the dandelion-like aircraft, that is, the canopy configuration has weakening effect on airflow fluctuations. In addition, an evaluation method for unsteady boundary Reynolds number and load capacity of a dandelion-like aircraft is presented. The proposed method aims to plan a reasonable number of filaments (or porosity) for further designing dandelion-like aircraft with flight stability and high load capacity under aerodynamic conditions at different Reynolds numbers.

Asteroid detection is of great significance to the study of the formation of the solar system and the origin of life. However, there are many types of asteroids, and they are far away from the earth, and the understanding of their various characteristics is not clear, which brings huge technical challenges to the landing and attachment of star catalogs. At present, the world is mainly based on surround, overflight, and short-term contact detection, and long-term attachment detection has not yet been realized. In order to solve the long-term attachment detection requirements of asteroids, focusing on the geological characteristics of various types of stars, this paper proposes a new type of asteroid attachment mechanism based on the beetle bionic theory, which can realize intelligent and flexible attachment and has strong adaptability. Around this design, this paper analyzes the mechanism of adhesion and realizes the adaptive matching of unascertained terrain landing point adhesion. On this basis, a prototype of the asteroid landing attachment mechanism was developed and verified by experiments. The experiment proved that the mechanism has strong multiterrain matching ability and can obtain an adhesion force of not less than 36 N on ordinary concrete ground.

Triply periodic minimal surface (TPMS) lattices are promising lightweight impact absorbers, but high-fidelity finite element modeling is costly, and uniform designs can develop high stress peaks during densification. This study presents a voxel-based finite element framework and a topology–density dual-gradient (TDDG) TPMS absorber. A convergence study selected a voxel size of 0.33 mm, yielding a 1.11% relative-density error and converged mechanical responses. Compared with a converged C3D4 tetrahedral model, the C3D8R voxel model reduced wall-clock time from 4222 to 497 s. Following validation against quasi-static compression tests, P, G, and IWP topologies at 20%, 30%, and 40% relative densities were screened. IWP20 and P40 were assigned to the impact- and support-facing regions and connected by normalized sigmoid interpolation. Under a 125 J impact, simulations predicted that TDDG-IWP20-P40 reduced peak nominal impact stress by 32.2% and 24.6% relative to U-P30 and DG-P20-P40, respectively, while maintaining comparable SEA. Additional simulations at 62.5 and 160 J confirmed lower peak stress than U-P30, with the added benefit over density-only grading becoming more pronounced at higher impact energy. Progressive crushing and delayed densification demonstrate the potential of TDDG TPMS absorbers for impact-load mitigation and future aerospace buffer designs.

To support in situ lunar regolith resource utilization for a lunar base Controlled Ecological Life Support System (CELSS), this study selected the nitrogen-fixing cyanobacterium Nostoc commune and halophyte Suaeda salsa (L.) Pall. based on extremophile soil amelioration theory. Three cultivation treatments were established: Nostoc commune monoculture (Group A), co-culture of N. commune and S. salsa (Group B), and S. salsa monoculture (Group C). Stratified sampling (0–0.5 cm surface, 1–1.5 cm middle, 2–3 cm deep) was conducted on day 45 to quantify pH, electrical conductivity (EC), organic matter, total nitrogen, available macro/meso/trace elements, and elemental correlation of plant residues. The results showed that both species survived in lunar regolith simulant; co-culture generated significant synergistic growth promotion for S. salsa. All treatments significantly reduced initial alkaline pH (8.80 ± 0.1). Group A neutralized surface/middle layers most effectively and maximized surface available N/K; Group C exhibited superior surface available P activation; Group B achieved uniform vertical pH/EC regulation and stable carbon–nitrogen residue accumulation. Residual biomass acted as a stable C/N reservoir and altered medium/trace element bioavailability via adsorption and complexation. Group A is suitable for N/K-deficient regolith, Group C for P-limited substrates, and Group B provides comprehensive long-term balanced nutrient supply matching CELSS demands. This study verifies extremophile-based lunar regolith bioremediation and provides differentiated amelioration strategies for lunar in situ resource utilization.