15 research outputs found
On the construction of characteristic specialty of the local applied undergraduate for the talent training of new engineering course
Combine the requirements of new engineering construction and required by China 2025 for professional personnel training, and meet the industry's demand for high-quality technical personnel. This paper takes the mechanical major as an example, puts forward the construction of characteristic specialty for the construction of new engineering course. Reforming the original talent training mode, strengthening the training of engineering application ability and innovative practice ability, and building a characteristic professional teaching and practice system that meets the needs of enterprises and serves local industries. Throughout the project teaching method and the whole teaching process, which is based on engineering practice education center, furthermore, it deepen cooperation between colleges and enterprises, production and education integration, which establishing an all-round quality guarantee and monitoring system. And it cultivates application-oriented engineering practice and innovation ability of the foundation
On the construction of characteristic specialty of the local applied undergraduate for the talent training of new engineering course
Combine the requirements of new engineering construction and required by China 2025 for professional personnel training, and meet the industry's demand for high-quality technical personnel. This paper takes the mechanical major as an example, puts forward the construction of characteristic specialty for the construction of new engineering course. Reforming the original talent training mode, strengthening the training of engineering application ability and innovative practice ability, and building a characteristic professional teaching and practice system that meets the needs of enterprises and serves local industries. Throughout the project teaching method and the whole teaching process, which is based on engineering practice education center, furthermore, it deepen cooperation between colleges and enterprises, production and education integration, which establishing an all-round quality guarantee and monitoring system. And it cultivates application-oriented engineering practice and innovation ability of the foundation
Research on Electrochemical Controllable Machining Technology of Small-Sized Inner Intersecting Hole Rounding
Small-sized inner intersecting holes are a common structure for large engine nozzles, hydraulic valves, and other parts. In order to ensure the uniform and stable fluid state in the intersecting hole, it is necessary to process the fillet at the intersecting line and accurately control the fillet radius. Limited by the structure and size, the rounding of the small-sized inner intersecting hole is a technical problem, and the traditional machining methods have problems, in terms of efficiency and accuracy. In order to solve this problem, electrochemical machining technology was applied to the rounding of small-sized inner intersecting holes. According to the structure of inner intersecting holes, an electrochemical rounding processing scheme with built-in fixed cathode was designed. The electric field distribution of different cathode shapes was analyzed using finite element method software. The influence of processing voltage and processing time on the current density distribution was studied for different cathode shapes, to determine the most reasonable cathode shape. Taking the inner intersecting hole with a diameter of 2 mm as the research object, and according to the analysis of the influence of processing voltage on the processing effect, a suitable control factor for controlling the rounding was processing time, and the optimal processing voltage was obtained. The formulas of fillet radius and processing time were obtained by regression analysis and verified using machining examples. The results provide a feasible method for the accurate and controllable machining of small-sized inner intersecting hole rounding
Design of a Parallel Quadruped Robot Based on a Novel Intelligent Control System
In order to make a robot track a desired trajectory with high precision and steady gait, a novel intelligent controller was designed based on a new mechanical structure and optimized foot trajectory. Kinematics models in terms of the D-H method were established to analyze the relationship between the angle of the driving joint and the foot position. Inspired by a dog’s diagonal trot on a flat terrain, foot trajectory planning in the swing and support phases without impact were fulfilled based on the compound cycloid improved by the Bézier curve. Both the optimized cascade proportional–integral–derivative (PID) control system and improved fuzzy adaptive PID control system were applied to realize the stable operation of a quadruped robot, and their parameters were optimized by the sparrow search algorithm. The convergence speed and accuracy of the sparrow search algorithm were verified by comparing with the moth flame optimization algorithm and particle swarm optimization algorithm. Finally, a co-simulation with MATLAB and ADAMS was utilized to compare the effects of the two control systems. The results of both displacement and velocity exhibit that the movement of a quadruped bionic robot with fuzzy adaptive PID control systems optimized by the sparrow search algorithm possessed better accuracy and stability than cascade PID control systems. The motion process of the quadruped robot in the co-simulation process also demonstrates the effectiveness of the designed mechanical structure and control system
Profile Evolution and Cross-Process Collaboration Strategy of Bearing Raceway by Centerless Grinding and Electrochemical Mechanical Machining
Roundness is one of the most important evaluation indexes of rotary parts. The formation and change of roundness in the machining of parts is essentially the formation and genetic process of profile. Centerless positioning machining is one of the main surface finishing methods of rotary parts. The rounding mechanism of centerless positioning machining determines its unique roundness profile formation and genetic characteristics. How to eliminate the roundness error of centerless positioning machining has become one of the important issues in the research of high-precision rotary part machining. This paper explores the influence of process parameters on the roundness error from the perspective of profile evolution during centerless grinding and electrochemical mechanical machining, with the aim of providing a cross-process collaboration strategy for improving bearing raceway accuracy. Through an experiment of centerless grinding, the influence law and mechanism of process parameters on the profile are discussed. On this basis, electrochemical mechanical machining experiments are designed to explore the variation rules and mechanisms of different profile shapes in the machining process. The cross-process collaboration strategy is studied, and reasonable parameters of centerless grinding and electrochemical mechanical machining are determined. The results show that in the centerless grinding stage, increasing the support plate angle can form a multiple-lobe profile with high frequency within a wide range of process parameters. Electrochemical mechanical machining can effectively smooth the high-frequency profile and appropriately expanding the cathode coverage can improve the roundness error and reduce the requirement of initial accuracy of a multiple-lobe profile workpiece to a certain extent. Therefore, the combined machining technology of “centerless grinding + electrochemical mechanical machining” provides an efficient technical means to realize the precision machining of rotary parts such as bearing raceways
Design of a Parallel Quadruped Robot Based on a Novel Intelligent Control System
In order to make a robot track a desired trajectory with high precision and steady gait, a novel intelligent controller was designed based on a new mechanical structure and optimized foot trajectory. Kinematics models in terms of the D-H method were established to analyze the relationship between the angle of the driving joint and the foot position. Inspired by a dog’s diagonal trot on a flat terrain, foot trajectory planning in the swing and support phases without impact were fulfilled based on the compound cycloid improved by the Bézier curve. Both the optimized cascade proportional–integral–derivative (PID) control system and improved fuzzy adaptive PID control system were applied to realize the stable operation of a quadruped robot, and their parameters were optimized by the sparrow search algorithm. The convergence speed and accuracy of the sparrow search algorithm were verified by comparing with the moth flame optimization algorithm and particle swarm optimization algorithm. Finally, a co-simulation with MATLAB and ADAMS was utilized to compare the effects of the two control systems. The results of both displacement and velocity exhibit that the movement of a quadruped bionic robot with fuzzy adaptive PID control systems optimized by the sparrow search algorithm possessed better accuracy and stability than cascade PID control systems. The motion process of the quadruped robot in the co-simulation process also demonstrates the effectiveness of the designed mechanical structure and control system
A Multi-Strategy Improved Arithmetic Optimization Algorithm
To improve the performance of the arithmetic optimization algorithm (AOA) and solve problems in the AOA, a novel improved AOA using a multi-strategy approach is proposed. Firstly, circle chaotic mapping is used to increase the diversity of the population. Secondly, a math optimizer accelerated (MOA) function optimized by means of a composite cycloid is proposed to improve the convergence speed of the algorithm. Meanwhile, the symmetry of the composite cycloid is used to balance the global search ability in the early and late iterations. Thirdly, an optimal mutation strategy combining the sparrow elite mutation approach and Cauchy disturbances is used to increase the ability of individuals to jump out of the local optimal. The Rastrigin function is selected as the reference test function to analyze the effectiveness of the improved strategy. Twenty benchmark test functions, algorithm time complexity, the Wilcoxon rank-sum test, and the CEC2019 test set are selected to test the overall performance of the improved algorithm, and the results are then compared with those of other algorithms. The test results show that the improved algorithm has obvious advantages in terms of both its global search ability and convergence speed. Finally, the improved algorithm is applied to an engineering example to further verify its practicability
A Multi-Strategy Improved Arithmetic Optimization Algorithm
To improve the performance of the arithmetic optimization algorithm (AOA) and solve problems in the AOA, a novel improved AOA using a multi-strategy approach is proposed. Firstly, circle chaotic mapping is used to increase the diversity of the population. Secondly, a math optimizer accelerated (MOA) function optimized by means of a composite cycloid is proposed to improve the convergence speed of the algorithm. Meanwhile, the symmetry of the composite cycloid is used to balance the global search ability in the early and late iterations. Thirdly, an optimal mutation strategy combining the sparrow elite mutation approach and Cauchy disturbances is used to increase the ability of individuals to jump out of the local optimal. The Rastrigin function is selected as the reference test function to analyze the effectiveness of the improved strategy. Twenty benchmark test functions, algorithm time complexity, the Wilcoxon rank-sum test, and the CEC2019 test set are selected to test the overall performance of the improved algorithm, and the results are then compared with those of other algorithms. The test results show that the improved algorithm has obvious advantages in terms of both its global search ability and convergence speed. Finally, the improved algorithm is applied to an engineering example to further verify its practicability