This paper studies solar sail heliocentric inclined elliptic displaced orbits (HIEDOs) with the application of reflectivity control devices (RCDs). In the solar sail HIEDO, the angle between the line from the Sun to the focus and the elliptic orbital plane is variable. A novel method is given to solve the sail attitude angles and the state of RCDs to achieve HIEDOs. Furthermore, this paper analyzes the problem of multiple solar sail formation flying (MSSFF) around HIEDOs, which consists of a chief and multiple deputies. The chief moves in an HIEDO and does not need to obtain the information from the deputies. The deputies need to receive the information from the chief, and an undirected connected graph is adopted to represent the information exchange structure between the deputies. Considering the convergence speed and reliability of the solar sail formation system, an innovative finite-time fault-tolerant distributed coordinated control scheme is devised. Under this control scheme, the deputies can consistently converge to the expected solar sail formation configuration within a finite time, even in the presence of the actuator effectiveness faults within a certain range. Finally, an example is used to verify the validity of the designed control scheme.

Space deployable masts, as one of the most widely used branches of space deployable structures, can provide driving, positioning, and transmission functions for spacecraft in orbit, which are irreplaceable in complex space activities. The nonmagnetic telescopic tubular mast (NMTTM) is designed and manufactured by the Shenyang Institute of Automation, Chinese Academy of Sciences, aboard the SATech-01 satellite to keep the magnetic probe assembly away from magnetic interference and realize global magnetic field measurement. The NMTTM can withstand complicated vibration and shock during rocket launching in the retracted state of 0.95 m, while it can be stably released and deployed to 5.28 m in orbit. NMTTM was successfully launched into Sun-synchronous orbit on 27 July 2022, fully deployed, and generated the positioning signal after a duration of 19 min and 16 s for the deployment process on 7 November. This paper focuses on the whole process of NMTTM from mission requirements to structure design and manufacture, through to releasing, deployment, and locking technology, environmental simulation tests, up to on-orbit deployment verification, which provides valuable experience for the subsequent development and application of large-scale space deployable masts.

Flasher origami pattern has been widely utilized to improve the stowage efficiency of deployable structures. Nevertheless, flasher origami cannot be folded fully flat, and they still have great potential for optimization in terms of storage volume and folding creases. In this paper, a flat foldable equiangular spiral folding pattern inspired by the sunflower disk is introduced. Then, a parametric design method for this equiangular spiral crease diagram is introduced in detail. Subsequently, a kinematic model of the equiangular spiral folding pattern is established based on the kinematic equivalence between rigid origami and spherical linkages. A simulation of the developed model demonstrates that the equiangular spiral folding pattern can be folded flat. Using the folded ratio as an evaluation index, the calculated results and experiments show that the equiangular spiral crease pattern can yield fewer creases and improve stowage efficiency in comparison to flasher origami pattern. Equiangular spiral folding pattern can save a considerable amount of space and provide a new approach to spatially deployable structures.

Miniaturized, multifunctional, and economical on-orbit service satellites have been increasingly used with the continuous increase of space exploration missions. In this paper, an innovative deployable manipulator is designed, named Cubot, which can be stowed in 1 U-sized (10 cm × 10 cm × 10 cm) space. With CubeSat as the carrier, the deployable Cubot aims to achieve a variety of on-orbit operation tasks including space debris removal and space station on-orbit maintenance, for future on-orbit servicing, assembly, and manufacturing (OSAM). A kinematics modeling method of a space manipulator with passive joints is proposed, and the motion equation of the manipulator is derived. Considered the elastic potential energy stored in the passive joint during deployment, the momentum change of Cubot is simulated and analyzed. As the main forced element, the end effector is analyzed using FEA. Dynamic stress response with respect to the force distribution and the clamping angle is analyzed to evaluate mechanical performances of the end-effector component. Deployment tests are conducted to verify the feasibility of Cubot based on a principled prototype, which aims to provide engineering and practical experience for the development of this field.