The tearing mechanical properties and the deformation field distribution of 45 degree oblique direction of the crack tip was studied on the stratospheric airship envelope reinforced by plain woven Kevlar-fiber composite. Here, the material samples were prefabricated with the initial length of 20mm unilateral incision, and the digital speckle correlation experimental method was used to obtain the perpendicular crack tip displacement and strain fields with artificial spots under mono-axial tear test. The results show the deformation field changes with the characteristic of discrete step and the strain concentration phenomenon, and the strain concentration zone expands as increasing tensile load. The warp and weft step maximum displacement reaches 6.00mm and 1.7mm, and deformation in every step exhibits a diminishing step law, the warp deformation in the rear area of the crack tip are evenly, while the shear and weft strain volatile in a wide range

Inflatable structures have many potential applications in space collapsible structures, this paper based on the premise of the same exploring features on the Planetary Exploration Device (PED) designs a new type of inflatable and lightweight model of PED. The device structure is designed to be a wheel style, which can be folded together in the transport process and in non-working state. Comparing with traditional devices, the new Wheeled Planetary Exploration Device (CWPED) reduces the space of transporting the exploration equipments and decreases the transport costs, moreover, this device provides convenient conditions for the equipment package of the CWPED, and there are evident advantages in the aspects of handing, solar absorption, volume and quality. This article mainly introduces the preliminary design of the CWPED, and the structural characteristics of the device, the principle of motion control and the design of wheeled body skin material are analyzed.

Inflatable space vehicle (ISV) has a variety of advantages of light mass, volume changeability and low cost, and becomes the hotspot in space vehicle research recently. But most researchers concentrate their efforts on applications of ISV in their dedicated domains, and the holistic viewpoint of ISV is indistinct. In this paper, the new developing space vehicle, ISV is classified into flatness, lenticula, sphere and cabin in brief due to its different structures and applications. Each type owns its special materials for folding, inflation-deployment, rigidization and resistibility in the space rigorous environment. Materials utilized in typical ISV are summarized subsequently, which can be sorted by polymer films, flexible rigidizable composites and multiple-layer laminates. Finally, the properties of ISV materials including environment endurance, mechanics, fabrication technologies and special functions are concluded, which is useful in material design and optimization.

Original defects in the envelope material easily torn damage under overpressure, when the stratospheric airship in use. This paper based on linear elastic theory studied the tear strength of envelope material containing initial center crack and proposed theoretical model for this problem. Choose Vectran fiber as a reinforcing layer of stratospheric airship envelope material, Combined with digital speckle method measuring tear strength of envelope materials containing different initial center crack length. Comparative analysis found that the theoretical model applicable to estimate the tear strength of envelope material, that center initial crack width ratio is less than 50%.It estimation error within 5% .It satisfies the requirement of engineering application accuracy.

For High altitude airship (HAA) with long time affected by space harsh environment, due to the occurrence of natural light radiation aging physical and mechanical properties, fiber-reinforced airship envelope material results in degradation of the mechanical load performance, even causing damage to the balloon airship. Based on the ground aging simulation of the airship envelope material under the natural light, the morphology of airship envelope material in the natural aging process can be observed and the specimen comparison test is carried on for its fracture strength and breaking elongation to qualify its mechanical properties. The specimens with the axial angle of 0°and 90°were respectively tested to get its mechanical properties and the comparative analysis on degradation of fracture strength and breaking elongation before and after its 720h aging is developed too. The test results shows that the mechanical properties of different specimens decrease, wherein the maximum degradation is 0° specimens and that of 90°specimens t is not very significant weakening. Natural aging characteristics of airship envelope material provide support for the design and improvement of anti-aging properties of the airship envelope material.