Search

Based on the review of planetary drilling and coring technologies, this paper elaborates the mechanical properties of planetary regolith and the preparation method of the soil simulant. Then, the experimental and theoretical drilling and coring characteristics are analyzed respectively. Meanwhile, the self-adaptive drilling strategy containing the drilling states recognition and autonomous drilling control are carefully researched. Based on the above foundations, the technical prospects and advices have been proposed for China lunar exploration. [ABSTRACT FROM AUTHOR]

The thin Martian atmosphere provides the necessary condition for Mars unmanned aerial vehicle (UAV) flight. The research background, flight environment and technical difficulties of the Mars UAVs are discussed. Furthermore Mars UAVs developed by different institutes worldwide are summarized. The difficulties of the Mars UAVs in aerodynamic theory, flight control and system integration are combed. The simulation and experimental achievements of the Mars UAVs are also summarized and the development trends of the Mars UAVs are forecasted. [ABSTRACT FROM AUTHOR]

The hexapod mobile robot, which can bear the heavy load and traverse in the unknown environment of the lunar surface, is a necessary device for lunar exploration. Although the hexapod robot walking over a rugged terrain can be accomplished by employing the ground contact and attitude information, and can make a reflex action when encountering the small obstacles, however, the obstacle avoidance based on visual information is an important issue in the field of the legged locomotion when faced with the insurmountable obstacles. For an electrically-driven and radially-symmetrical hexapod robot, the terrain modeling for the lunar surface is based on the information from the laser range finder. In this paper, a virtual trunk body model is presented to achieve the autonomous obstacle avoidance strategy in the unknown environment, and the real-time optimal feasible directions and minimum distance are acquired to avoid the obstacles. The path trajectory of the trunk body and foot trajectories are planned to walk toward the feasible direction. The experimental result shows that the hexapod robot can track the yaw angle and in real time accurately from the obstacle avoidance method to achieve the obstacle avoidance autonomously in the unknown environment. The key techniques will lay a foundation for the research of the heavy-duty multi-legged robots for lunar exploration. [ABSTRACT FROM AUTHOR]

When the wheels of a manned lunar roving vehicle (LRV) are driven by the same torque both on the Earth and the Moon, the vehicle will produce the different linear acceleration caused by the different gravities. In view of the above questions, a single wheel is concentrated, and the force model of the vertical load, drawbar pull force, and driving torque is established. Then, by analyzing the moving condition of producing the same linear acceleration for a single wheel both on Earth and the Moon, the imitation algorithm for driving the wheel is derived. Finally, to verify the imitation algorithm, the linear accelerations of a single wheel under three conditions, including the lunar condition, the Earth condition with the imitation algorithm, and the Earth condition without the imitation algorithm, are compared. The comparison results show that the wheel on Earth driven by the torque using the imitation algorithm can produce the same linear acceleration with that of the wheel on the Moon. However, the wheel without using imitation algorithm cannot produce the same linear acceleration. [ABSTRACT FROM AUTHOR]

For the lunar regolith drilling mission, a novel screw-cone drill is proposed and a theoretical model of chip removal performance of the screw-cone drill is established. Based on the model, the drill structural parameters are optimized. On that basis, the cutting parameters of the screw-cone drill is analyzed and the prediction model of drilling load is built based on the theory of passive earth pressure. The prediction model is well verified by the experimental results. The research results show that the screw-cone drill has a better performance of cuttings discharging compared with the linear blade drill. The research results would have an important reference value for drilling bit design for China′s lunar exploration and sampling project. [ABSTRACT FROM AUTHOR]

The wheel slippage affects the rover mobility and localization accuracy in lunar terrains. In view of the rover slip ratio detection problem, this paper suggests a method for estimating the rover vehicle wheel slip ratio by detecting trace imprint image frequency feature. The defuse analysis model of trace imprint is built by analyzing the wheel-terrain-interaction process and trace imprint formation mechanism. The slip ratio estimation model based on the imprint image fundamental frequency characteristics is built by the defuse analysis model of trace imprint and the frequency domain analysis of trace imprint image. Further, the trace imprint image process and frequency domain feature extraction process for this method are also proposed. The slip ratio can be measured without contact only by detecting the fundamental frequency of the trace imprint image precisely. The test results show that the relative accuracy of the wheel slip ratio is 3% by using this method. [ABSTRACT FROM AUTHOR]

The conditions of the deployable units which constitute the double-layer hoop truss deployable antenna mechanism are proposed. A lightweight crank slide block type unit with high stiffness is designed. The comprehensive evaluation index of the unit features is established，and the evaluation and optimization of the element characteristics of the seven types of deployable units are discussed. The structure dimension of the optimally selected deployable unit is optimized, and the optimization design parameters of the deployable unit are also obtained. The structure design of the double-layer hoop truss deployable antenna mechanism with a caliber of 20m is completed. Furthermore，the research not only develops the two kinds of new sample machines, both contained with elastic-plastic hinge，one for the single-layer hoop truss deployable antenna mechanism and the other for unit-structure of the double-layer hoop truss antenna，but also takes experimental verification for the deployable functions and the repeated accuracy of these two sample machines. At last，the correctness and feasibility of the deployable unit proposed in this paper and the large-size hoop truss deployable antenna mechanism are verified. [ABSTRACT FROM AUTHOR]