Autonomous Recovery from Spacecraft Plan Failures by Regulatory Repair While Retaining Operability

Pre-designed spacecraft plans suffer from failure due to the uncertain space environment. In this case, instead of spending a long time waiting for ground control to upload a feasible plan in order to achieve the mission goals, the spacecraft could repair the failed plan while executing another part of the plan. This paper proposes a method called Isolation and Repair Plan Failures (IRPF) for a spaceship with durable, concurrent, and resource-dependent actions. To enable the spacecraft to perform some actions when a plan fails, IRPF separates all defective actions from executable actions in the pre-designed plan according to causal analysis between the failure state and the established plan. Then, to address the competition between operation and repair during the partial execution of the plan, IRPF sets up several regulatory factors associated with the search process for a solution, and then repairs the broken plan within the limits of these factors. Experiments were carried out in simulations of a satellite and a multi-rover system. The results demonstrate that, compared with replanning and other plan-repair methods, IRPF creates an execution plan more quickly and searches for a recovery plan with fewer explored state nodes in a shorter period of time.

An Attitude Prediction Method for Autonomous Recovery Operation of Unmanned Surface Vehicle

The development of launch and recovery technology is key for the application to the unmanned surface vehicle (USV). Also, a launch and recovery system (L&RS) based on a pneumatic ejection mechanism has been developed in our previous study. To improve the launch accuracy and reduce the influence of the sea waves, we propose a stacking model of one-dimensional convolutional neural network and long short-term memory neural network predicting the attitude of the USV. The data from experiments by “Jinghai VII” USV developed by Shanghai University, China, under levels 1–4 sea conditions are used to train and test the network. The results show that the stabilized platform with the proposed prediction method can keep the launching angle of the launching mechanism constant by regulating the pitching joint and rotation joint under the random influence from the wave. Finally, the efficiency and effectiveness of the L&RS are demonstrated by the successful application in actual environments.

GDM progenies exhibit sex disparity in metabolism after respective therapies of insulin, glibenclamide and metformin in dams during pregnancy

Background： The drug treatments for the pregnant women with gestational diabetes mellitus (GDM) have been concerned with their effects on both mothers and offspring. The aim of this study was to compare the intergenerational effects of insulin, glibenclamide and metformin on glucose and lipid metabolism in the offspring born to GDM mice. Methods: The murine GDM was induced by high fat diet. The offspring were grouped based on the treatments in maternal mice. ITT and GTT were performed at 4th week and 8th week of age, respectively. Serum levels of TC, TG, HDL-C and LDL-C plus hepatic levels of TG and TC, were respectively determined by enzymatic kits. Western blotting was conducted to detect related proteins in the livers from offspring. Results: The normalization of the dyslipidemia, hepatic lipid abnormality and insulin insensitivity elicited by the respective therapies of insulin, glibenclamide and metformin during maternal pregnancy still persisted in the male adult offspring. Specifically, the decreases in plasma TC, TG, LDL-C levels (29%, 37.8% and 57.7%, respectively, p˂0.05) and hepatic lipid contents (TC 31.3% and TG 39.2%, p˂0.05), the increases in hepatic phosphorylation levels of AKT, CPT1A ,PPAR- α and PPAR-γ (57.1%, 91.7% , 68% and 173.3%, respectively, p˂0.05) and the inhibition of G6Pase, PEPCK, HMGCS1 (35.7%, 68.8% and 77.3% respectively, p˂0.05) were still observed in the male offspring born to treated GDM mice from 4th to 8th week of age. Unexpectedly, the female progeny born to untreated GDM mice showed an autonomous recovery in glucose and lipid metabolism. Conclusions: Respective treatments in GDM mice during pregnancy with insulin, glibenclamide and metformin have the long-term persisted effects in male offspring, while female progenies born to untreated dams showed an autonomous inhibition of intergenerational relay of glucose and lipid dysregulation. Our current findings may shed a new light into GDM clinical practice.

Marine UAV–USV Marsupial Platform: System and Recovery Technic Verification

Heterogeneous unmanned systems consisting of unmanned aerial vehicles (UAVs) and unmanned surface vehicles (USVs) have great application potential in marine environments. At present, the fully autonomous recovery of UAVs is a key problem that restricts any significant application of a heterogeneous unmanned system. This paper presents a novel fully autonomous recovery system, covering the entire process of recovery of small fixed-wing UAVs on mobile platforms at sea. We describe methods or solutions for the key problems encountered by the current system, including active modeling of the UAV–USV heterogeneous platform motion model, accurate estimation of the highly dynamic relative motion of the heterogeneous platform, dynamic analysis of the arresting cable system, and compliance control of the manipulator recovery system. Based on these methods, a physical simulation platform for the fully autonomous recovery system, including an actively adjustable arresting cable, manipulator compliance recovery system, and other subsystems, is developed and verified through experiments. The experiments show that the system proposed in this study can achieve full autonomous recovery of a small ship-based fixed-wing UAV with a high success rate in a short period. This system is the foundation for practical applications of UAV–USV heterogeneous unmanned systems in the marine environment.

Increasing Patient Empowerment in TKA-Recovery Via a Mobile Application: an Observational Study

During the last few years, total knee arthroplasty has evolved from basic surgery to restore basic function, to a fast-track procedure to relief pain and get the patients back to a high level of activity.. However, the way physiotherapy is performed, remained the same. This paper presents the results of 185 patients that used a mobile health application to track their recovery. Adherence and clinical results were evaluated and reported. Our study demonstrated an excellent patient acceptance and compliance of the outpatient autonomous recovery app. Patient satisfaction was outstanding, and functional recovery was securely within conventional range.