Recent Patents on Engineering - Volume 17, Issue 1, 2023

Data mining has been instrumental in the extraction of some useful knowledge from data. The purpose of data mining has always been to focus on searching for methods to extract instead of revealing the implicit models of the data. The outcome of the process of data mining is the knowledge that is represented by different visualization techniques. Knowledge obtained through data mining is not effective without the intervention of a domain expert who uses that knowledge to make a decision. On the other hand, human participation has the potential to influence and predispose decisions. Human participation in the process of data mining is still subjective and cannot be automated. A possibility to look into this quandary is the conversion of these subjective factors into some measurable parameters. This predicament leads to the development of an area that can be referred to as "Wisdom Mining," which will consist of procedures to add wisdom to the extracted knowledge. Wisdom mining, if it is proposed as an extension to data mining, exhibits the need for certain factors, methods, and measures beyond the methods and measures used in the data mining process. The factors proposed in this article for a seamless transition from data to wisdom mining are context, utility, time, and location. There are two possibilities to use these factors for the extraction of wisdom from data. One is to develop new algorithms for wisdom mining from scratch, keeping these four factors as major placeholders. The second approach is to add these four factors to the existing algorithms of data mining to get wise patterns as outcomes. The paper proposed a second approach for laying the foundation of this new domain of wisdom mining.

Background: Friction stir welding technology is widely applied in the welding of dissimilar metal materials because of its high welding efficiency, low welding process cost, high welding joint strength and reliability, and green environmental protection. The research on the processing methods and working principle of friction stir welding of dissimilar metals is beneficial to improve the mechanical properties of the joint and reduce weld defects. Therefore, the development of reliable friction stir welding technologies for dissimilar metals joining has been paid increasing attention in recent years. Objective: The study aims to satisfy the processing of various dissimilar metals and improve the joint performance and weld defects. Friction stir welding has developed into bobbin tool friction stir welding and stationary shoulder friction stir welding. Methods: This paper retraces various current representative patents relative to friction stir welding, bobbin tool friction stir welding, and stationary shoulder friction stir welding. Results: Through the investigation of a large number of patents on friction stir welding, the main current existing problems, such as poor mechanical properties of the joints and defects in the welds, are summarized and analyzed. In addition, the development trend of friction stir welding in dissimilar metal welding is also discussed. Conclusion: The research on friction stir welding methods and devices is beneficial to improve the mechanical properties of welded joints and reduce weld defects. More correlative patents will be invented in the future.

Background: Three-dimensional printing technology is widely applied in the medical, aviation, automotive, construction, and consumer goods industries because of its characteristics of forming shapes without mold, not limited by part complexity, and fully digitalization control. The control system, a core element of a three-dimensional printer, controls the orderly working procedure of all elements of the printer and plays a vital role in the printing efficiency and printing quality of the three-dimensional printing. Therefore, the development trend of the control system of the three-dimensional printer has been paid increasing attention. Objective: To evaluate the latest technology in the 3D printer control system, we assess the existing 3D printer control system to improve printing accuracy and printing efficiency. In this review, the open-loop control system and closed-loop control system of the 3D printer are discussed emphatically. In conclusion, the future research direction of a 3D printer control system is discussed. Methods: This paper reviews the current various representative patents related to the control system of a 3D printer. Results: Through investigating a large number of patents on the control system of 3D printers, the closed-loop control system and the opened-loop control system of the 3D printer are analyzed, and the development trend of the 3D printer control system is discussed. Conclusion: The optimization of the control system of the 3D printer is conducive to increasing printing efficiency and printing quality in the 3D printing process. More relevant patents need to be invented in the future.

Background: Surface condition of mechanical parts has a significant impact on the machine performance. The use of surface microtexture technology based on bionics is an effective method to improve the comprehensive performance of the surface of machine parts. Surfaces with microscopic pits, convex-hulls, microgrooves, and scale textures can reduce wear, improve friction, enhance lubrication, decrease drag, and minimize noise. Surface microtexture technology has been widely used in many types of machinery, embodying various properties in working conditions. Objective: The purpose of this study is to provide an overview of recent patents and related research on surface microtexture technology, and to serve as a guide for future applications. Methods: The paper describes the development of surface microtexture technology, reviews the representative patents on surface microtextures and their applications in industrial field, including cutting tools, bearings, gears, blades, etc. The advantages and disadvantages of various surface microtextures are discussed. Results: In this study, the influence of surface microtexture on friction, wear, lubrication, sealing, noise reduction, and hydrophobicity is examined through the analyses of various microtexture produts. The main problems in future development of surface microtexture technology are summarized. Conclusion: Machine elements with different types of microtexture perform different functions. The geometrical parameters of the microtexture contribute greatly to the surface properties of the machine elements. Therefore, the surface performance of machine elements can be improved by designing and optimizing the geometric parameters of the microtexture. In the future, more patents focused on surface microtexture will be reported.

Background: Under the influence of complex external environment and the internal parameter perturbation of the system itself, many interference problems hinder the development of the controlled object according to the predetermined trajectory. Objective: The objective of this study is to provide the corresponding anti-interference control methods for different degrees of interference and introduce their respective characteristics. Methods: This paper mainly summarizes the application examples of anti-interference control algorithms in the face of different interference problems, which are mainly divided into three categories. Especially two new concepts, whose names are composite anti-interference control and innovative anti-interference control algorithm design, are presented. At the same time, this paper not only summarizes the outstanding contribution of anti-interference control in the mechanical field, but also expounds on the application examples of coupling of anti-interference control in electrical aspect and describes the application of anti-interference control in other planets. Results: From the interference problem on the earth to the anti-interference control of outer space, the control algorithm shows the unique charm step by step. In the future, to cope with the complex and changeable environment, the anti-interference algorithm will continue to be optimized in depth, letting the control system run steadily in direction of fast, accurate and stable on the expected track. Conclusion: Anti-interference control plays an important practical role in the control of systems. Whether in the mechanical field or coupling in other aspects such as electrical, it can help the system run better according to the needs of the controller. It is effective and reasonable to combine different strategies for the systems, so that the systems are more accurate and stable.

Background: The large amount of data generated by intelligent bearings still needs to be processed manually, which results in low efficiency, untimely access to status and fault diagnosis information, and a lack of the best maintenance period for machinery and equipment. Objective: By analyzing the research achievements and patents on intelligent bearings, a summary of the development trend provides a reference for the development of intelligent bearings. Methods: This paper introduces the key technologies associated with intelligent bearings and reviews various representative patents relating to intelligent bearings. The advantages and disadvantages of these patents are also analyzed. Results: At present, the development of intelligent bearing technology relies primarily on the sensor bearing. Most intelligent bearing patents have utilized the bearing gap to best arrange monitoring devices, and in some cases, the bearing structure has been changed to obtain the best arrangement. These intelligent bearings can achieve a degree of self-monitoring. For the integration of detection data processing and big data, research on the self-adaptation aspect of bearing is the initial step. Conclusion: Adapting to the host operation requirements is the direction of the development of intelligent bearings, and this requires intelligent bearings to involve self-awareness, self-decision, selfdiagnosis, and self-adaptation functions. In the future, these functions should be realized from the perspectives of systematization, diversification of monitoring information, and intelligent data analysis.

Background: As a kind of device applied to grinding, the robot grinding end-effector, combining force control structure, adaptive structure, and other structures, has been widely used in machine grinding. Grinding end-effectors can greatly help industrial robot technology used in operations that require continuous contact, such as polishing, grinding, deburring, chamfering, and assembly. Therefore, the structure design of the end-effector will become an inevitable trend in the research on robot grinding in the future. Objective: The existing grinding end-effectors for robot grinding are summarized, and their classification, characteristics, and development are introduced. Methods: Various products and designs related to grinding end-effectors are summarized. The structural features, differences, and applications of typical grinding end-effectors are introduced. Results: Three typical end-effectors are analyzed. The structural features and functions are summarized, and the development trend has been prospected. The current situation and future research direction of grinding end-effector products and patents are discussed. Conclusion: Grinding end-effectors are classified into the force-controlled grinding end-effector, the adaptive grinding end-effector, and the special structure grinding end-effector. The grinding end-effector plays an important role in promoting the development of the robot grinding industry, improving the surface quality of parts and the finishing process. The grinding end-effector needs further improvement in image processing, humanization, force control, and so on. More in-depth research should be carried out in this direction.

Background: The digital twin as an integrated technology has been widely used in the medical field. Currently, the application of digital twin technology in the field of respiratory science is mostly theoretical exploration, with less applied technical research. Therefore, this has greatly limited the development of lung-airway models and devices that cope with digital twin technology in clinical settings and has also hindered the development of digital twin technology. Objective: The aim of this study is to propose an effective physical model to simulate the human environment as an efficient means to develop and improve the digital twin technology. Methods: A representative set of patents related to physical models of the respiratory tract and lungs is presented, including methods for model building and ways to assess and predict the diagnosis of respiratory diseases. Results: Current patents are analyzed and compared in three aspects: physical models, model building methods, and respiratory disease assessment and prediction. A digital twin modeling approach, including mechanical effects, biological evolution, physiological tissue changes, and physical entity coupling is proposed based on the hardware support involved in rapid prototyping techniques and method patents. The advantages and disadvantages of the existing models are analyzed, and the systematicity, applicability, modeling techniques, and fidelity of the digital twin physical model are discussed. Conclusion: Lung airway models are already based on complete morphological data, but purely physical models cannot reproduce the real environment of the human body. Therefore, in order to reach the heights of digital twins, the intervention of numerical theory and related auxiliary hardware is often required.

Background: With the rapid development of spatial technology and mankind's continuous exploration of the space domain, expandable space trusses play an important role in the construction of space station piggyback platforms. Therefore, the study of the in-orbit assembly strategy for space trusses has become increasingly important in recent years. The spatial truss assembly strategy proposed in this paper is fast and effective, and it is applied for the construction of future large-scale space facilities effectively. Objective: The four-prismatic truss periodic module is taken as the research object, and the assembly process of the truss and the assembly behaviors of the spatial cellular robot serving for on-orbit assembly are expressed. Methods: The article uses a reinforcement learning algorithm to study the coupling of truss assembly sequence and robot action sequence, then uses a q-learning algorithm to plan the strategy of the truss cycle module. Results: The robot is trained through the greedy strategy and avoids the failure problem caused by assembly uncertainty. The simulation experiment proves that the Q-learning algorithm of reinforcement learning used for planning the on-orbit assembly sequence of the truss periodic module structures is feasible, and the optimal assembly sequence with the least number of assembly steps obtained by this strategy. Conclusion: In order to address the on-orbit assembly issues of large spatial truss structures in the space environment, we trained the robots through greedy strategy to prevent failure due to the uncertainty conditions both in the strategy analysis and in the simulation study. Finally, the Q-learning algorithm in reinforcement learning is used to plan the on-orbit assembly sequence in the truss cycle module, which can obtain the optimal assembly sequence in the minimum number of assembly steps.

Background: Microfabrication has gradually become a hot spot in the manufacturing industry in recent years, and in the process of microfabrication, the processing of microelectrodes is very important. The precision and error control of the microelectrodes play a vital role in the final machining results. Based on digital image processing technology and Matlab software, this paper designs a microelectrode automatic measurement system. Through preprocessing and image segmentation of the microelectrode image, the electrode size can be obtained quickly. Compared with the size measured by the microscope, the detection size of this system has an error of less than 4% and coaxiality measured error within 6%. The results show that the system has the characteristics of high measurement accuracy and fast detection speed and can meet the requirements of rapid size measurement of microelectrodes. Objective: The purpose of this research is to improve the efficiency of size detection when manufacturing a large number of microelectrodes by developing an automatic detection system. This system has made relevant optimization on the error control of the size detection to ensure that the error is within the allowable range. Methods: Firstly, the original images of the microelectrodes were obtained using an electron microscope. Secondly, the necessary image processing had been done for the image: gray processing, binarization, median filtering, morphological processing, and large background noise removal. These processes are automatically carried out in the system. In addition, three methods of measuring coaxiality error are proposed, and the first measurement algorithm with the minimum deviation is selected and put into the system, which can ensure the accuracy of coaxiality offset. Finally, the diameter of the microelectrode was measured, and the coaxiality offset of the microelectrode was measured by various methods. After the comparison of the measured values manually, the algorithm with the minimum deviation was selected and put into the system. Results: The diameter and coaxiality of the cylindrical microelectrode and the cylindrical microelectrode with a ball head are successfully measured, and the measurement error is within 4% after comparison, showing that the automatic measurement system has great measurement efficiency. Conclusion: The comparison of the electrode measurement results of this system with the manual measurement results shows that the automatic measurement system developed in this paper can meet the accuracy requirements for measuring the diameter of the microelectrodes, and can significantly improve the measurement efficiency compared with manual measurement.

Background: Preparation of the superhydrophobic surface on the metal substrate can effectively solve the problems of easy corrosion and easy ice coating of metal materials, and it is given the functions of self-cleaning, oil-water separation, lubrication and drag reduction. Constructing micro-nano rough structures and reducing surface potential energy are the key factors in preparingsuperhydrophobic surfaces. There is no macroscopic cutting force between the electrode and workpiece in the WEDM process, the surface roughness can be changed by controlling the energy, and the complex shape can be manufactured by increasing the degree of freedom. The WEDM method has broad application prospects in the preparation of the superhydrophobic surface. Objective: To verify the feasibility of preparing the hydrophobic surface by WEDM, the micro-nano structure of the EN-GJL-250 (Gray cast iron material) surface was processed by the WEDM method, and the effect of surface roughness on the hydrophobicity of the surface was studied; Simultaneously, in the process of WEDM, the effects of peak current and pulse width on the surface roughness and static contact angle (CAs) of the EN-GJL-250 were studied. The purpose was to improve and control the surface hydrophobicity of the EN-GJL-250. Methods: The micro-nano structure was fabricated on the EN-GJL-250 surface by WEDM. Using the single factor test, by setting different peak currents and pulse widths, the surface roughness and CAs of the processed EN-GJL-250 can be measured. Results: Using the WEDM machine tool, by inserting set dimensions and regular contour parameters, the micro-nano structure with hydrophobic properties can be machined on the EN-GJL-250 surface. Different WEDM processing parameters produce rough microstructures of different scales and affect the hydrophobicity of the EN-GJL-250 surface. Experimental results show that with the increase of pulse width and peak current, the surface roughness of EN-GJL-250 also increases, and the number and size of craters in the microstructure increase, which improves the hydrophobicity of the surface of EN-GJL-250; When the peak current is 16A and the pulse width is 32us, the CAs of the prepared EN-GJL-250 surface is the highest. Conclusion: The surface roughness microstructure of EN-GJL-250 is processed by WEDM, which can realize the hydrophobicity of the surface. The pulse width and peak current will affect the roughness of the processed surface, thereby affecting the hydrophobic properties of the surface. The research data in this paper provides theoretical support for the industrial production of superhydrophobic EN-GJL-250 surfaces.