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This brief investigates the predefined-time stabilization attitude control for multi-segment cable-driven space continuum robot system in the presence of external time-varying disturbances. By utilizing the theorem of practical predefined-time stability, an adaptive attitude controller based on a nonsingular terminal sliding mode is developed, so that the attitude error can converge into a small neighborhood of the origin within a predefined time. A suitable Lyapunov function is chosen to prove the stability of the robot system. The numerical simulation results demonstrate the effectiveness and superiority of the proposed control strategy.

Spacecraft pose estimation plays an important role in an increasing number of on-orbit services: rendezvous and docking, formation flights, debris removal, and so on. Current solutions achieve excellent performance at the cost of a huge number of model parameters and are not applicable in space environments where computational resources are limited. In this paper, we present the Squeeze-and-Excitation based Spacecraft Pose Network (SESPNet). Our primary objective is to make a trade-off between minimizing model parameters and preserving performance to be more applicable to edge computing in space environments. Our contributions are primarily manifested in three aspects: first, we adapt the lightweight PeleeNet as the backbone network; second, we incorporate the SE attention mechanism to bolster the network’s feature extraction capabilities; third, we adopt the Smooth L1 loss function for position regression, which significantly enhances the accuracy of position estimation.

This present study is a secondary analysis that investigated the association between mean achieved BP in the two treatment groups (SBP target, 110 to <130 vs. 130 to <150 mmHg) and their cardiovascular outcomes in the STEP study (60–80-year-old patients with hypertension).Patients achieving a target in the intensive-treatment group have better cardiovascular outcome than patients achieving a target in the standard treatment arm, supporting the cardiovascular benefits of maintaining SBP <130 mmHg.J-shaped relationships were observed between mean achieved SBP and cardiovascular outcomes (with the nadir around 130 mmHg), but not for stroke.Graphical Abstract