It is an important link to realize the safe production of coal mine to accurately identify the support state of the side guard and judge whether the side guard interferes with the shearer. This paper presented an anomaly detection method of side guard based on improved YOLOv5s, which set up a data set of side guard called hb_data2021 and improved the YOLOv5s model. It could be judged whether the state of the side guard was abnormal, according to the label classification based on the detection results of the improved YOLOv5s. In order to reduce the parameters of YOLOv5s model, MobileNetV3 and the lightweight attention mechanism NAM (normalization-based attention module) were used to replace the backbone feature extraction network. In order to improve the detection accuracy of side guard, the loss function was improved to α-CIoU and knowledge distillation was conducted. The experimental results showed that after distillation, the average precision of the network was improved by 1.0%, the parameters was reduced by 33.4%, and the reasoning speed was accelerated by 34.2%; the abnormal detection method of side guard based on the improved YOLOv5s had a good effect. It could be deployed on the NVIDIA Jetson Xavier platform to meet the requirements of real-time video detection. Transplanting the detection model to the embedded platform of the patrol robot can realize the abnormal detection of the side guard and meet the actual needs of the coal industry.

Aiming at the problem that the horizontal rotating equipment of space station cabin is easy to deform in the length direction after bearing load of 30 t, a six-point leveling algorithm and synchronous control method was proposed. On the basis of installing one screw lifting outrigger at each of the four corners of the original horizontal rotating equipment of space station cabin, one screw lifting outrigger was added at the center of two long sides, and the levelness of the horizontal rotating equipment upper plane was within 0.001° through the coordinated control of the height of each screw lifting outrigger, so as to ensure the centroid stability and no structure deformation of the space station cabin. At the same time, the feasibility of six-point leveling algorithm and synchronous control method was verified by theoretical simulation. The experimental test showed that the proposed method had good leveling effect, and the synchronous control error of six screw lifting outriggers was less than 8 ms; after leveling, the maximum error of upper plane levelness of the horizontal rotating equipment was 0.000 8°, and the maximum deformation was 0.074 mm, which could be ignored and met the expected goal. The results showed that the application of the six-point leveling algorithm and synchronous control method effectively avoided the deformation in the length direction of the horizontal rotating equipment of space station cabin after bearing load of 30 t, improved the levelness of the horizontal rotating equipment and extended its service life, and ensured the centroid stability of the space station cabin after it was placed on the horizontal rotating equipment, which could provide technical support for the subsequent space station assembly process.

Aiming at the problems of traditional rigid picking manipulators, such as small scope of application, poor environmental adaptability and great damage to fruits and vegetables, a rigid-flexible coupling pneumatic soft picking manipulator for crabapple picking was designed. According to the characteristics and picking requirements of crabapple, the six-finger wrapped picking form was determined. Taking Longfeng fruit as an example, the bending angle calculation model for the soft finger of picking manipulator was established, and the bending angle of single finger was determined; the HY-E620 type silicone was selected as the material of soft fingers through the tensile contrast experiment of three kinds of silicone materials; the ABAQUS finite element simulation analysis of the influence of various structures on the bending performance of soft fingers was carried out, and the optimal structure was determined; the corresponding relationships between the bending angle and the output force of a single soft finger under different driving pressure conditions were measured by experiments, and the three-finger grasping experiment for various fruits under the driving pressure of 0.08 MPa was carried out, which verified the rationality of the soft finger structure. Finally, a six-finger wrapped pneumatic soft picking manipulator was trial-produced, and the picking experiments were carried out on crabapple, apple, pear and orange. The results showed that the designed picking manipulator could not only pick clustering crabapples containing 3?6 fruits with a success rate of 80%, but also pick apples, pears, oranges and other spherical fruits, which had a certain versatility, and could provide a new idea for the design and research of fruit picking manipulator.

In order to meet the rehabilitation training needs of patients with lower limb motor dysfunction at different stages, a traction lower limb rehabilitation robot that could realize the training modes of lying and sitting postures was proposed in view of the single training mode of existing lower limb rehabilitation robots. Firstly, according to the motion mechanism and bionic principle of human lower limbs, a five-degree-of-freedom hybrid mechanism configuration was designed. Then, the kinematics model of the robot was established, and the forward and inverse kinematics solutions were calculated, respectively. Then, taking the workspace coincidence degree between the end of human lower limb and the end of robot as the objective function, the mechanism parameters of robot were optimized by the genetic algorithm, and the effective workspace ratio of human lower limb in the sagittal plane of the human-machine system was 0.71. Finally, three kinds of rehabilitation training trajectories including CPM (continuous passive motion), circular motion and spiral motion were planned, and a robot prototype was built according to the optimized mechanism parameters. Through motion capture experiments, the rationality of the robot structure design and optimization results and the correctness of trajectory planning were verified, which indicated that the robot could meet the rehabilitation needs of patients with lower limb motor dysfunction.

Aiming at the problems of insufficient oil suction and slow system response caused by the unreasonable parameters of the distribution check valve in single plunger pump system, a multi parameter optimization method based on linear regression was proposed. Firstly, the simulation analysis of single plunger pump system was carried out by AMESim software, and the relationship between different check valve parameters (spring pre-tightening force, spring stiffness and valve core mass) and oil inlet flow was discussed by using MATLAB fitting toolbox. Then, on the basis of using the principal component analysis method to eliminate the correlation between the parameters, taking the oil inlet flow as the dependent variable, the spring pre-tightening force, spring stiffness and valve core mass as the independent variable, and the value range of each parameter as the constraint condition, a check valve parameter optimization model based on linear regression was established, and the genetic algorithm was used to optimize the solution. Finally, according to the parameters of the check valve before and after optimization, the simulation analysis and experimental verification of the single plunger pump system were carried out. The simulation results showed that the oil inlet flow was increased by 21.3% after optimization; the experimental results showed that the actual oil inlet flow was increased by 16.8% after optimization. The research shows that the proposed multi parameter optimization method is an effective method, which can provide reference for the parameter optimization of the distribution check valve in single plunger pump system.

Rational modification of cycloidal gear can greatly improve the transmission performance and bearing capacity of RV (rotary vector) reducer. In order to further optimize the contact stress of the "inverse arch-shaped " tooth profile, a two-stage modification method was proposed based on the comprehensive analysis of the influence of combined modification on the meshing force and contact stress of the inverse arch-shaped tooth profile. In this method, the cycloidal gear tooth profile was divided into two sections, and different modification quantities were adopted for different working sections according to the needs, so as to design the cycloidal gear tooth profile more flexibly. Taking RV-40E reducer as an example, the force analysis model of cycloidal gear was established by using MATLAB software, and the modification amount and equation of the new tooth profile were determined according to the two-stage modification method; then, the finite element model of contact between cycloidal gear and needle tooth was established by ANSYS software, and the contact stress between the new tooth profile and the inverse arch-shaped tooth profile was compared. The theoretical calculation results showed that the maximum contact stress of the new tooth profile was reduced by 8.34%; the finite element simulation results showed that the maximum contact stress of the new tooth profile was reduced by 4.39%, and the possible error sources were analyzed. The research shows that the two-stage modification method can improve the contact stress of cycloidal gear tooth profile and prolong the service life of cycloidal gear, which provides a certain reference for the modification design of cycloidal gears.

Lightweight is an important way to make automobile industry develop towards safety, energy conservation and environmental protection. The Al/CFRP (carbon fiber reinforced plastic) hybrid material can improve the lightweight effect while taking into account the material cost and structural crashworthiness. In order to explore the best combination mode of Al/CFRP hybrid thin-walled structure with square cross section, firstly, Al square tubes, CFRP square tubes and Al/CFRP hybrid square tubes were prepared, and quasi-static crushing experiments were carried out. Then, the finite element model that could accurately simulate the crushing response of Al/CFRP hybrid square tube was established. Finally, the multi-objective certainty and reliability optimization design for the Al/CFRP hybrid square tube was carried out by combining experimental design method, agent model technique, multi-objective optimization algorithm and Monte Carlo simulation technology, and the reliability optimization solution with good effect was verified by simulation. The quasi-static crushing experiment results showed that the Al/CFRP hybrid square tube had excellent crashworthiness; the optimization results showed that the constraint reliability of the reliability optimization solution was 10.96% higher than that of the certainty optimization solution, which greatly reduced the failure probability and had stronger practicability. The research results are expected to provide a reference for the optimal design of Al/CFRP hybrid thin-walled energy-absorbing components.

In order to improve the current loop frequency response capability and speed response performance of the surface-mounted permanent magnet synchronous motor, and aiming at the problem of excessive unknown parameters of the expected interconnection matrix due to the coupling of d-axis and q-axis current in the passive controller design process, a new design method of passive controller based on current decoupling was proposed by combining with voltage feedforward decoupling control. Firstly, according to the energy balance principle and voltage feedforward decoupling control, the port control Hamilton system with dissipation (PCHD) model of surface-mounted permanent magnet synchronous motor based on current decoupling was constructed. Then, the passive controller of surface-mounted permanent magnet synchronous motor was designed by the interconnection and damping assignment passive-based control (IDA-PBC) method, and the voltage feedforward decoupling control was introduced in the design process to eliminate the coupling between d-axis and q-axis current, so that the unknown parameters of the expected interconnection matrix were reduced from 3 to 1. Finally, the test platform of surface-mounted permanent magnet synchronous motor was built for experimental verification. The experimental results showed that when the passive controller based on current decoupling was used in the current loop of surface-mounted permanent magnet synchronous motor, the q-axis current response frequency increased from less than 250 Hz to more than 333 Hz; the speed response time at rated speed decreased from 0.16 s to 0.11 s, the overshoot decreased from 2.0% to 0.6%, and the steady-state error decreased from 5.98 r/min to 1.15 r/min. The research results can provide a new idea for the passive controller design of permanent magnet synchronous motor.

In view of the problem that the transmission accuracy of RV (rotate vector) reducer decreased due to the wear of its parts in the working process, a dynamic reliability model of the transmission accuracy of RV reducer considering the wear of cycloid wheel was established, the reliability of transmission accuracy was analyzed, and the tolerance of key parts and the modification parameters of cycloid wheel were optimized. Taking a heavy-load RV reducer as the research object, the wear depth of cycloidal gear was calculated by using Archard wear formula, the distribution of gear tooth profile wear was analyzed, and the wear amount was predicted by using Gaussian process regression model based on numerical simulation data; the reliability model of RV reducer transmission accuracy with dynamic wear was established, and its dynamic reliability was solved by Monte Carlo method; an optimization model was established with the dynamic reliability of transmission accuracy as the constraint condition, the minimum machining cost and the minimum maximum wear in the rated life cycle as the optimization objectives, and the optimal solution was obtained adopting multi-objective genetic algorithm. The results showed that after optimization, the wear of cycloidal gear was slightly increased, and the machining cost of reducer was obviously reduced; the reliability of transmission accuracy of the reducer had been significantly improved, and the reliability within the rated life of 6 000 h met expected requirements. The research results can provide reference for the design of high-precision RV reducer.

In order to overcome the problems of low accuracy of the magnetic field and analytical thrust model of large stroke Maxwell reluctance actuator caused by the large magnetic flux leakage under large air gap and the uneven distribution and strong nonlinearity of magnetic field distribution in the air gap, the calculation method of three-dimensional magnetic flux leakage distribution of the reluctance actuator was improved by using the magnetic circuit modeling method considering the weighted magnetic flux leakage coefficient of integrated Gaussian function. Thus, an analytical model which could accurately describe the functional relationship between thrust and input current was obtained, which provided an important basis for the design and control of this kind of actuator. Firstly, the working magnetic circuit of the large stroke Maxwell reluctance actuator before and after considering magnetic flux leakage was established, and the function of permanent magnet bias magnetic circuit and the reason why it still had nonlinearity after using permanent magnet bias structure were analyzed. The analytical thrust model for large stroke Maxwell reluctance actuator was established by using the Ampere’s loop law, the Ohm’s law of magnetic circuit and the superposition of magnetic field. Then, a weighted magnetic flux leakage coefficient calculation method based on Gaussian distribution curve was proposed to optimize the analytical model, and the three-dimensional magnetic field distribution and magnetic flux leakage coefficient of the large stroke Maxwell reluctance actuator were analyzed and calculated by using the finite element simulation software, so that the analytical thrust model considering the weighted magnetic flux leakage coefficient was obtained. Finally, the thrust test system for large stroke Maxwell reluctance actuator was built, and the accuracy of the analytical model was verified by comparing the calculated thrust of analytical model before and after optimization with the simulated thrust and the measured thrust. The results showed that the root mean square error of the analytical model after optimization was only 11.1% of that before optimization. At the same time, the root mean square error between the calculated thrust of analytical model after optimization and the measured thrust was less than 0.6 N, which verified the high accuracy of the optimized model. The research results have certain significance and reference value for the design of new ultraprecision driving components in high-end micro/nano-manufacturing equipment and measuring instruments.

With the increasing complexity and diversity of 3D printed parts, the single-material parts can no longer meet various special performance requirements. Functionally graded material parts have gradually become a research hotspot in rapid prototyping manufacturing industry. In order to meet the manufacturing requirements of functionally graded material, a spatial mapping modeling method for functionally graded material based on coordinate transformation was proposed. The key of this method was to effectively combine geometry information with material information. Firstly, the material space of functionally graded material model was constructed by using the single gradient source method and multi-gradient source method. When the cross-gradient source model was encountered, the material distribution was calculated by using a specific intersection operator with a certain weight ratio. Then, in the process of combining the geometric space and the material space, the coordinate system of material space and geometric space was cleverly cooverlapped through coordinate transformation to realize the mapping of material space to geometric space, so as to obtain a functionally gradient material model with material information. The required functionally graded material model could be obtained by modifying the gradient source, material distribution function and coordinate transformation method. The results of visual analysis of the instance model through Visual Studio 2019 and OpenGL programming languages showed that the proposed modeling method greatly shortened the modeling time compared with most valuation modeling and non-valuation modeling methods, and fundamentally solved some problems of insufficient storage space and cumbersome modeling process caused by some algorithms. The spatial mapping modeling method for functional gradient material based on coordinate transformation can provide a new modeling method for the additive manufacturing industry and has good application value.

Due to the complex terrain and landform in Sichuan and Chongqing area, there are some problems such as larger distortion of excitation signal and larger dissipation of excitation energy when vibroseis vibrates on rural roads. In order to solve this problem, a road excitation model of vibroseis was established, an evaluation system of road excitation effect of vibroseis was established, a study on the road excitation effect of vibroseis in Sichuan and Chongqing area was carried out, and the energy dissipation of road excitation of vibroseis was analyzed. The results showed that the proposed evaluation system could comprehensively evaluate the road excitation effect of vibroseis in Sichuan and Chongqing area; compared with gravel soil road, the ground transmission energy was 48.31% lower, the amplitude of surface contact center point was 77.44% lower, the amplitude of interaction force was 77.44% lower, the signal distortion was 34.69% higher, when vibroseis vibrated on non-defective cement road and the excitation effect was poor; the road defects had obvious weakening effect on the excitation effect, especially the round hole road defects, in which the ground transmission energy decreased by 54.94%, the amplitude of the surface contact center point decreased by 5.57%, the amplitude of the interaction force decreased by 21.16%, and the signal distortion increased by 36.17%; when vibroseis vibrated on roads in Sichuan and Chongqing area, the structural energy dissipation of the flat plate was relatively large, accounting for about 90% of the total energy dissipation of the system. The research results can provide theoretical guidance for the improvement of rural road excitation effect of vibroseis in Sichuan and Chongqing area.

In order to solve the problem that the traditional tunnel drilling rig is not convenient for rapid installation and operation due to its huge volume when conducting the water exploration and drainage operation in the tunneling roadway, an airborne water exploration and drainage drilling rig of excavating and anchoring all-in-one machine was designed. This paper introduced the structure of the airborne water exploration and drainage drilling rig and the overall structure of its automatic electronic control system, designed the hardware of the control system, analyzed its work flow, and conducted industrial experiments in the factory and underground for the water exploration and drainage drilling rig. The experimental results verified the feasibility of the control system of the designed drilling rig. The developed water exploration and drainage drilling rig can significantly improve the efficiency of water exploration and drainage, and has a good application prospect.

In order to solve the problems of long processing cycle and low production efficiency caused by inputting the size information of manually measured paper drawings or model samples into the computer and converting it into electronic processing drawings in garment, packaging and other processing industries, a control system of plane machining machine tool based on machine vision was proposed to realize the rapid detection of paper drawings or model samples. The master-slave motion control system was built by using "ARM+DSP" mode, and the functional modules of each part of the system were designed. A visual detection system of "industrial computer+industrial CCD (charge coupled device) camera+light source control" was built. An improved FAWS (feature adaptive wavelet shrinkage) algorithm was proposed by combining the FAWS algorithm and the sparrow search algorithm to reduce image noise, and the Canny algorithm was used to complete achieve image edge detection so as to achieve the accurate extraction of image contour. The processing programs of image contour extraction, contour data conversion to processing data, data communication, etc. were designed to realize rapid detection based on machine vision and human-computer interaction in the system processing process. Finally, the system was tested and the actual machining effect was evaluated. The results showed that the proposed control system of plane machining machine tool could not only significantly improve the production efficiency, but also reduce the error of image contour. Its performance is stable and reliable, and has certain engineering practical value.