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In order to meet the needs of intelligent perception of the driving environment, a point cloud registering method based on 3D NDT-ICP algorithm is proposed to improve the modeling accuracy of tunneling roadway environments. Firstly, Voxel Grid filtering method is used to preprocess the point cloud of tunneling roadways to maintain the overall structure of the point cloud and reduce the number of point clouds. After that, the 3D NDT algorithm is used to solve the coordinate transformation of the point cloud in the tunneling roadway and the cell resolution of the algorithm is optimized according to the environmental features of the tunneling roadway. Finally, a kd-tree is introduced into the ICP algorithm for point pair search, and the Gauss–Newton method is used to optimize the solution of nonlinear objective function of the algorithm to complete accurate registering of tunneling roadway point clouds. The experimental results show that the 3D NDT algorithm can meet the resolution requirement when the cell resolution is set to 0.5 m under the condition of processing the point cloud with the environmental features of tunneling roadways. At this time, the registering time is the shortest. Compared with the NDT algorithm, ICP algorithm and traditional 3D NDT-ICP algorithm, the registering speed of the 3D NDT-ICP algorithm proposed in this paper is obviously improved and the registering error is smaller.

In order to realize the autonomous cutting for tunneling robot, the method of cutting trajectory planning of sections with complex composition was proposed. Firstly, based on the multi-sensor parameters, the existence, the location, and size of the dirt band were determined. The roadway section environment was modeled by grid method. Secondly, according to the cutting process and tunneling cutting characteristics, the cutting trajectory ant colony algorithm was proposed. To ensure the operation safety and avoid the cutting head collision, the expanding operation was adopt for dirt band, and the aborting strategy for the ants trapped in the local optimum was put forward to strengthen the pheromone concentration of the found path. The simulation results showed that the proposed method can be used to plan the optimal cutting trajectory. The ant colony algorithm was used to search for the shortest path to avoid collision with the dirt band, and the S-path cutting was used for the left area to fulfill section forming by following complete cover principle. All the ants have found the optimal path within 50 times iteration of the algorithm, and the simulation results were better than particle swarm optimization and basic ant colony optimization.

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In this paper, an analysis method is proposed to determine capture tolerance capability of an orthogonal distributed satellite capture device that exhibits characteristics, including modularization, miniaturization, extensibility, and peripheral layout. The verifiable limit poses of the satellite are obtained when the pose error of the satellite reaches the boundary of the tolerance domain of the capture device. A dynamic model of a body combined with a satellite and robotic arm, and a contact dynamic model between the combined body and the capture device are established to lay the foundation for the capture determination of satellites in limit poses. A pose-iteration method is used to predict the pose trajectory of the satellite during the capture process, and the results of the satellite capture in the limit poses are obtained. The tolerance capability of the capture device is obtained on verifying the success or failure of the capturing satellite in limit poses. The tolerance capability of an example is analyzed by utilizing the proposed analysis method and is tested via simulation software. With respect to the four typical limit poses in the tolerance domain, the simulation results indicate that the capture device successfully captures the satellite. The results reveal the accuracy of the obtained tolerance and also validate the effectiveness of the proposed tolerance analysis method. The contact dynamics model is imported into the method of tolerance capability analysis to realize the accurate calculation of the time-varying dynamic tolerance capability of the capture device.INDEX TERMS Orthogonally distributed, capture device, tolerance capability, pose iteration method.