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The intuitive and effective haptic feedback interaction is essential for human–machine interfaces. However, most current commercial haptic feedback solutions are rigid, simplex, and insufficient to fully immerse users in virtual and teleoperated environments. Here, we report the design, fabrication and performance of a low-cost and lightweight self-sensing actuator (SenAct) that provides accurate force and vibration feedback to recreate the tactile perception. The SenAct shows good performance such as fast response (10 ms), high robustness (>10,000 cycles), and large output force (up to 1.55 N) with high controllable resolution (up to 0.02 N) based on the real-time closed-loop control. It is capable of providing the corresponding haptic feedback to the wearer through external force or vibration signal input. With this prototype, we presented a haptic feedback glove that supports precise operation by enhancing immersion and comprehensive sensation. Furthermore, we demonstrated it could shape appropriate interaction in different scenarios, including touching or grasping objects in virtual reality and teleoperation, illustrating its potential applications in human-in-loop interaction system and metaverse.

Teleoperation robots remain superior to fully automated robots in complicated and unstructured environments (e.g., in-orbit assembly). However, the collision risk is also greatly increased in these environments. Therefore, the teleoperation robot should possess the capability of collision risk perception and be configured with security assistance strategy to improve safety and efficiency. With this objective in mind, this paper proposes a collision risk assessment system based on fuzzy theory, which comprehensively considers the effects of shortest distance, operation speed, and delay time. The introduction of fuzzy theory makes the risk assessment results more accurate. Furthermore, this paper also proposes a creative discrete expandable bounding box method to make the calculation of the nearest distance between complicated obstacles and the robot more efficient and faster. Secondly, to improve the safety and efficiency of teleoperation, this paper proposes a set of teleoperation assistance strategies for teleoperation robots based on collision risk. The strategies include partial view highlighting, variation in the motion mapping ratio, and haptic risk warning, all of which are achieved in the graphical interactive interface. Finally, this paper verifies the proposed collision risk model and the operation assistant strategy through experiments. The results show that the proposed fuzzy collision risk model has a correct trend with risk factors, and the proposed operation assistance strategies can effectively reduce the robot collision risk and improve the safety of teleoperation robots. In conclusion, this research contributes to the collision risk assessment and obstacle avoidance assistance strategy of teleoperation robots.

In order to support the development of high–precision spacecraft, the current state of the Stewart vibration isolation platform in the field of aerospace micro–vibration was surveyed. First, based on analyses of the causes and characteristics of spacecraft micro–vibration, the principles, characteristics, advantages and disadvantages of four vibration isolation technologies are summarized. Second, the development process of the Stewart vibration isolation platform, from structural proposal and theoretical calculation to application in various fields, is introduced. Then, the current state of kinematics, dynamics and braking control algorithms of the Stewart platform is investigated, and related work on rigid/flexible platforms in the field of aerospace micro–vibration is introduced in detail. Finally, the idea that the Stewart platform can be fabricated by 4D printing technology is proposed. The novel Stewart platform can be combined with artificial intelligence algorithms and advanced control strategies, allowing for further development in the direction of an integrated omnidirectional, full–frequency and multi–function platform with variable stiffness.

Shape memory polymers (SMPs) have been applied in aerospace engineering as deployable space structures. In this work, the coupled finite element method (FEM) was established based on the generalized Maxwell model and the time–temperature equivalence principle (TTEP). The thermodynamic behavior and shape memory effects of a single-arm deployment structure (F-DS) and four-arm deployment structure (F-DS) based on SMPs were analyzed using the coupled FEM. Good consistency was obtained between the experimental data and simulation data for the tensile and S-DS recovery forces, verifying that the coupled FEM can accurately and reliably describe the thermodynamic behavior and shape memory effects of the SMP structure. The step-by-step driving structure is suitable for use as a large-scale deployment structure in space. This coupled FEM provides a new direction for future research on epoxy SMPs.