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Chang’e-4 lunar rover is the first achievement of human exploration on the far side of the moon. New working environment brings challenges to the dormancy and wake-up of the lunar rover. The dormancy and wake-up constraints of the lunar rover are analyzed, including energy, thermal control, etc. Then combined with the complex terrain and relay communication, a dormancy and wake-up control strategy is designed for the lunar rover. The strategy includes skyline recognition, dormancy and wake-up time calculation, rover expected attitude calculation, sleeping position planning and moving, sleeping setting, wake-up setting and so on. Finally, the effectiveness of the control strategy is verified by the real on-orbit status.

Utilizing the in-situ reducing method, a reduced graphene oxide (rGO) paper for 13~14 um was obtained and exhibits great Terahertz (THz) absorbing capability. The absorption of rGO paper exceeds 43% in the whole frequency band from 0.3~1.2 THz and maximum absorption reaches 59.33% at 1.13 THz. This makes it possible to realize ultra-thin broadband THz absorbing materials.

China's first Mars rover Zhurong has successfully began its exploration on Mars surface. It is important to estimate the rover slip while driving on the Mars, for the slip has a negative impact on the navigation accuracy and passing safety. In this paper, we establish the slip estimation model by BP and GA-BP algorithm for Zhurong rover. Pitch and roll of the rover, average current and velocity of the wheel drive motors are selected as input features to train the model. All data are obtained by Zhurong validator's indoor slip experiment. The results demonstrate that genetic algorithm effectively optimizes the weights and thresholds of the BP network, so that GA-BP performs better than the BP neural network in rover slip estimation. The GA-BP model established in this paper has reference value for the slip estimation of Zhurong rover.

China's Zhurong rover successfully reached the Mars surface and began its exploration on May 22nd, 2021. As of June 15, the cumulative driving distance exceeded 100m. The rover will slop when it is driving on the Martian surface, which will affect the accuracy of scientific detection. In view of this phenomenon, an adaptive fuzzy control method based on slip compensation is proposed. The kinematics equation of the Zhurong rover in the process of curvature driving is established, and an adaptive fuzzy controller is designed to compensate the steering radius and driving time of the wheels in the slip process. The simulation results show that the method based on adaptive fuzzy control can compensate the deviation of the rover on the Mars surface. It effectively tracks the ground planning trajectory and has better tracking and security. Finally, the effectiveness of the controller is verified by on-orbit application.

Aiming at the problems of the low automation level of distribution network, the limited available monitoring data and the difficulty in fault location, this paper proposes a fault location method based on sequence current matching idea, which only uses the monitoring data of the first end of feeder in substation to realize fault location. The fault branch is located by matching the actual fault data with the data in node fault library. And then calculate the fault distance using the curve function of the fault branch, the fault distance is determined and the actual fault point is found. The analysis of an example shows that this method has a good positioning effects.

In the complex and dynamic urban road environment, conflicts in time and space between different traffic participants are inevitable. In this paper, a model to predict the trajectories of oncoming straight vehicles is proposed based on the Gaussian Process Regression (GPR) model with the consideration of analysis of left-turn potential conflict behaviors. Then, a conflict resolution method for left-turn behavior of autonomous vehicles at urban intersections and a driving action selection method considering multiple factors, such as safety, efficiency, comfort and altruism, are proposed. Experiments show that the model can guide the unmanned vehicles to complete the task with a success rate of more than 90%. The research results can provide decision-making support for autonomous vehicles passing through urban intersections safely.

This Paper conducts effective mining to wind vibration disaster data of power transmission line conductor by using the clustering analysis method. The main influential factors which cause different types of wind vibration disasters are analyzed. This paper laying a foundation for the subsequent correlation analysis and machine learning model. On the basis of K-Means method, the significant degrees of different influential factors on forecast of galloping, wind deviation and sub-span oscillation disaster are studied. The results show that: the span, conductor icing thickness and wind direction are main influential factors of conductor galloping; the included angle between wind and conductor and span are main influential factors of insulator wind vibration; the span, spacer span, and number of spacers are main influential factors of subspan oscillation.

The accurate and reasonable theoretical model of conductor vibration is one of necessary conditions for analyzing dynamics characteristics of conductor accurately. In this paper, low-order nonlinear dynamics characteristics, such as first-order natural frequency and steady state response of four-bundle and 8-bundles LGJ-500/45, has been analyzed by both theoretical (including traditional theoretical model and one in this paper) and test ways and compared to get the differences between them, which verified the validity of the conductor vibration model based on curved beam model. The result shows that the characteristics obtained from the model in this paper is more accurate that compared with the traditional model. Most importantly, conclusions in this paper provides theoretical and test basis for the further research on vibration of conductors.