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In the era of Industry 4.0, the demand fluctuation has become fiercer due to the characteristics of diversification, customisation, and uncertainty. Reconfigurability of manufacturing systems has been proven to be a useful and necessary feature when it comes to handling demand uncertainty. This feature can be achieved through the implementation of reconfigurable manufacturing system (RMS) and delayed reconfigurable manufacturing system (D-RMS). D-RMS is a subclass of RMS that focuses primarily on improving the convertibility of the manufacturing system. The two main phases involved in implementing D-RMS are part family formation and configuration design. Therefore, we proposed a multi-objective joint optimisation method of part family formation and configuration design according to the philosophy of D-RMS. Firstly, we develop a multi-objective joint optimisation model that takes into account investment cost, reconfiguration cost, similarity coefficient, and delayed reconfiguration to optimise the part family and configuration of D-RMS simultaneously. Three types of machine tools namely dedicated machine tools, flexible machine tools, and reconfigurable machine tools are considered in the optimisation model. Secondly, the non-dominated sorting genetic algorithm-III (NSGA-III) is adopted to solve the proposed multi-objective integer programming problem. Finally, numerical experiments are presented to demonstrate the effectiveness of the proposed multi-objective joint optimisation method. [ABSTRACT FROM AUTHOR]

Hybrid transmissions have attracted great attention in the automotive industry due to their energy-saving, low-emission properties, and have become a focus of research and development. This paper presents a new method to design the configuration of two mode power split hybrid transmission using the combination of the simple planetary gear trains (PGT). For this purpose, the hybrid transmission structure is divided into two substructures, which achieve different operation modes respectively. Then the output of one substructure is reconnected with the components of another substructure to obtain the complete hybrid transmission configuration. In addition, by adding additional shifting elements, the hybrid configurations can also realize the fixed gear mode as a traditional automatic transmission. As a result, 38 hybrid transmissions are obtained, and the kinematic analysis of a new configuration is performed for the subsequent optimization. Furthermore, using this decomposition and recombination method, the hybrid transmissions with multiple PGTs and different operation modes can be synthesized by changing the predefined modes. [ABSTRACT FROM AUTHOR]

The Sun-Earth L 2 libration point configuration is one of the options for space-based gravitational wave detection. Long-term configuration stability is crucial for high-precision measurements, challenged by the strong nonlinear dynamics of the Sun-Earth three-body system. This paper proposes an efficient design method and determines the feasible parameter domain for the libration point gravitational wave observatory. First, the dynamic model for the libration point configuration is established, and the stability indexes are defined. The sensitive parameters that affect the relative geometric configuration are discussed and the phase angle is found to be the key factor. Then, an efficient design method is proposed, and the procedure is divided into two steps. The phase angle of the Earth phase offset orbit and the libration point configuration are optimized successively. Finally, the proposed method is applied to the LAGRANGE mission concept. The results show that the three stability indexes decrease by 59%, 42% and 23%, respectively. Moreover, a mapping between configuration parameters and stability indexes is established. The feasible parameter domain for the stable libration point configuration is discussed. The feasible amplitudes domain in the x and z directions of the libration point orbit should be less than 6200 km and 42000 km, respectively, to guarantee configuration stability. This research could provide a reference for the stable design and implementation of gravitational wave detection missions utilizing libration point configuration in the future. • An efficient design method for the libration point GWs observatory is proposed. • Sensitive parameters of configuration are discussed; phase angle is the key factor. • Phase angle of Earth offset orbit and stability indexes are optimized successively. • A mapping between configuration parameters and stability indexes is established. [ABSTRACT FROM AUTHOR]

Copyright of Systems Engineering & Electronics is the property of Journal of Systems Engineering & Electronics Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

To meet the in-orbit construction needs of super-large spacecraft for ultra-long rod structures, this paper proposes an innovative on-orbit roll forming method for polyetheretherketone (PEEK)-based rod stock. This method ingeniously integrates temperature gradient control into a continuous deformation surface cavity design to achieve an efficient forming of resin rod components. A parametric model of the forming die cavity was established based on the comprehensive bending and downhill methods, and the boundary conditions for the temperature distribution gradient within the cavity were determined. Through the simulation and analysis of the PEEK rod curling and stitching forming process, the influence of the cavity configuration parameters on the forming load was determined. By constructing a test platform for the roll forming characteristics of resin rod components, the effects of different forming methods, stitching temperatures, and feed rates on forming quality and load were verified, and the main factors affecting the width of the welding zone, the roundness of the rod, and the straightness of the weld were analyzed. Experimental results show that the proposed continuous roll forming scheme can achieve an efficient and continuous forming of resin rod structures. When the length of the member is processed to 300 mm, at a formed rod diameter of 20 mm, by employing a cavity deformation zone length of 210 mm, a cavity clearance of 0.1 mm, a sheet width of 61 mm, a feed rate of 1 mm/s, and a sealing zone temperature setting of 335 °C, optimal rod forming quality can be achieved, characterized by a straightness error of 0.0133 ± 0.005 mm and a roundness error of 0.19 ± 0.07 mm. The proposal of this scheme provides a reliable basis for the continuous manufacturing of rod structures in the on-orbit construction of large space structures in terms of both the scheme and the parameter selection. [ABSTRACT FROM AUTHOR]

Capturing noncooperative targets in space has garnered continuous research interest in aerospace applications. This study addresses the demands of large-scale, multifaceted activities and varied working conditions for space capture missions by designing a space capture robot composed of multiple cable-driven manipulators operating in parallel. First, single- and multi-segment cable-driven robot models were designed, and a geometric model was subsequently built. The optimal number of segments was determined by analysing the condition number of a Jacobian matrix using the Monte Carlo method. Subsequently, based on the constant-curvature assumption, a kinematic model of the cable-driven space capture robot was formulated, and capture methods for different capture targets were designed using the Monte Carlo method. Finally, an eight-segment cable-driven robot prototype was developed, and compliance and driving experiments were conducted. This robot exhibits promising application potential for space noncooperative target capture and can be feasibly manufactured using on-orbit 3D machining technology. [ABSTRACT FROM AUTHOR]

Copyright of China Mechanical Engineering is the property of Editorial Board of China Mechanical Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of China Mechanical Engineering is the property of Editorial Board of China Mechanical Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The problem of lunar interferometric synthetic aperture radar (InSAR) satellite formation configuration design is studied. Firstly, the relative dynamic model of lunar InSAR satellite based on relative eccentricity/inclination (E/I) vector is established. Then, the long-term stable flight conditions of formation flying under the perturbation environment of lunar orbit are studied. Taking the relative altimetry accuracy and fuzzy altitude as optimization indexes, and considering the inter-satellite safety, the objective function of formation configuration design is given. In response to the existing research methods are unable to solve the multi-objective problem of configuration design, an improved multi-objective ant-lion optimization algorithm in applied to achieve the configuration design of lunar InSAR satellite formations. Simulation results show that the proposed algorithm in better in baseline utilization rate, which verities the adaptability and effectiveness of the proposed algorithm. [ABSTRACT FROM AUTHOR]

The permanent magnet couplings had problems of complex structure, difficult assem¬ly and poor resistance to eccentric load. In terms of transmission performance evaluation, the finite lement simulation calculation took a long time and the analytical calculation accuracy was low. There¬fore, a new type of cylindrical permanent magnet coupling configuration was designed. The trapezoidal magnet and the wedge slot may realize the self-priming assembly of permanent magnets. Aiming at his configuration, an equivalent magnetic charge-magnetic circuit analytical calculation method was proposed to calculate the transfer torque and an absorption-repulsion composite permanent magnet oupling configuration was designed. The transfer torques where the relative deflection of inner and outer rotors as 0°-45° and the foces responde to radial relative offset --3.8-3.8 mm of two perma¬nent magnet couplings were simulated and verified by experiments. The results show that the errors of he proposed analytical algorithm decreases 50% than that of the simulation results, and the analytical alculation time is shortened from 2 h to 2 min. Compared with cylindrical configuration, the maxi¬mum radial eccentric load of the suction-repulsion composite configuration is as 48.59%. Reasonable uggestions are put forward for design optimization of permanent magnet couplings. [ABSTRACT FROM AUTHOR]

A cloud manufacturing (CMfg) system is presented as a novel service- and customer-oriented manufacturing paradigm that integrates the distributed manufacturing enterprises to share their manufacturing capabilities or resources and collaborate as an interconnected system in a dynamic environment. Since the high performance of this system depends on the formation of a suitable group of manufacturing service providers, this paper develops an integrated c onfiguration design and capacity planning problem for the CMfg system by considering the dynamic environment of this system. In this regard, dynamic service providers and dynamic demand are considered as two aspects of the dynamic nature of this system. A multi-period multi-objective mathematical model is proposed by maximising the utilities of all three stakeholders of the system. Moreover, three extensions of a discrete multi-objective grey wolf optimiser (DMOGWO) algorithm are devised to solve the medium- and large-scale instances. A comprehensive computational experiment is conducted to assess the performance of the developed meta-heuristic algorithms. Furthermore, by carrying out a sensitivity analysis, some managerial insight is suggested for the managers. [ABSTRACT FROM AUTHOR]

The electrification of heavy duty commercial vehicles is one of the critical path for solving its problems of high energy consumption and high pollutant emission. And the configuration scheme design and parameter matching of electric drive systems are the foundation of heavy duty commercial vehicle electrification. The dual driving axles of heavy duty trucks are taken as the research object. Then, the electric drive configuration scheme and parameter matching of the dual electric driving axles are studied. Several kinds of electrical drive configurations are analyzed and compared. Then, the dual electrical drive axles are determined. Specifically, the number of driving motors and the number of transmission gears are determined. Based on the configuration scheme, the main components structural performance parameters are calculated according to the functional and performance requirements of the vehicle. These parameters include power, speed and torque of the driving motors, the speed ratio of the transmission device, and the terminal voltage and capacity of the power battery. Then, the dynamic model of the electric heavy commercial vehicle is developed based on the designed configuration scheme and the matched components parameters. The dynamic and economy performance of this vehicle are simulated using the model. The simulation results show that the maximum speed can reach 100 km/h, the maximum grade-ability can reach 30%, and the driving range exceeds 300 km. It is illustrated that the configuration and parameters of the electric dual driving axles can meet the heavy commercial vehicle performance requirements. In the end, the relevant research can provide theoretical and technical support for the electrification of heavy commercial vehicles.

Multipurpose，intelligent，and strong terrain adaptability are important trends in the development of helicopters in the future. The landing gear is a key component to ensure the safety of helicopter takeoff and landing. Due to the poor terrain adapt-ability of the traditional landing gear，a leg landing gear system is designed using the bionics design concept to solve the problem of the helicopter's smooth land observation in complex terrain environment. Starting from the design requirements of leg landing gear，the landing architecture is analyzed and the leg structure design is completed. Then，based on the designed leg mechanism，the kinematics analysis and dynamics analysis are completed，and the relevant models are established as the basis for the motion control of the leg landing gear. Finally，motion testing of the leg landing gear is completed in the laboratory，proving the rationality of the structural design and the stability in the lading.

The conceptual design of unmanned aerial vehicles (UAVs) presents significant multidisciplinary challenges requiring the optimization of aerodynamic and structural performance, stealth, and propulsion efficiency. This work addresses these challenges by integrating deep neural networks with a multiobjective genetic algorithm to optimize UAV configurations. The proposed framework enables a comprehensive evaluation of design alternatives by estimating key performance metrics required for different operational requirements. The design process resulted in a significant improvement in computational time over traditional methods by more than three orders of magnitude. The findings illustrate the framework's capability to optimize UAV designs for a variety of mission scenarios, including specialized tasks such as intelligence, surveillance, and reconnaissance (ISR), combat air patrol (CAP), and Suppression of Enemy Air Defenses (SEAD). This flexibility and adaptability was demonstrated through a case study, showcasing the method's effectiveness in tailoring UAV configurations to meet specific operational requirements while balancing trade-offs between aerodynamic efficiency, stealth, and structural weight. Additionally, these results underscore the transformative impact of integrating AI into the early stages of the design process, facilitating rapid prototyping and innovation in aerospace engineering. Consequently, the current work demonstrates the potential of AI-driven optimization to revolutionize UAV design by providing a robust and effective tool for solving complex engineering problems. [ABSTRACT FROM AUTHOR]

To enhance the reliability and self-healing of the system, the research on fault tolerance of the reconfigurable modular centralized control center is its development trend. Most of the previous research has focused on hardware redundancy. Improving fault tolerance performance is an essential topic in the research of centralized control platforms. Firstly, the problem of centralized fault tolerance in the working configuration of a reconfigurable manipulator is studied. The effect of each hinge on fault tolerance in the existing configuration is studied with the criterion of manoeuvrability and tolerable space. The fault module was first modelled to represent the system architecture information. A modular motion rule based on autonomous recombination technology is proposed. A self-organizing deformation algorithm with fault tolerance is studied. The fault tolerance of the motion pairs is compensated by adding a small number of motion pairs to ensure the configuration characteristics. With the addition of a failure compensation device, the joint's range of motion was reduced, and the fault tolerance rate was enhanced. After the failure of the robot arm, the fault tolerant control method can still ensure that the robot arm can perform work in its tolerable working space. The test results show that the fault tolerance analysis method is practical and feasible. It lays a theoretical foundation for the application in aerospace, industry and other fields. [ABSTRACT FROM AUTHOR]

Origami-inspired space deployable structures can be transformed from the folded states into the deployed states in orbit, which satisfied the demands of complex space missions and had been widely used in the space field. It remains to be investigated how the space deployable structures realized a large deployable ratio in the crease design process of origami patterns for the storage space limitation of spacecraft structures. Origami-inspired Regular Polygons Deployable Structures (RPDS) were proposed by designing the origami configurations and analyzing the deployable mechanism from existing space deployable structures, and a novel crease topology with three different approaches was presented in repeating origami modules to enhance the deployable ratio. The topology results indicated that the deployable ratio of RPDS can be increased effectively by shortening the storage height or performing multi-stage deployment, and the flexibility of RPDS can be verified by changing the shape of the central body. The configuration rationality and deployable reliability of RPDS are confirmed by kinematic modeling and numerical simulation. This study provides new insights into extraordinary geometrical and folding properties of origami-inspired deployable structures via configuration design and crease topology, which can be extended to other origami patterns in various origami-inspired applications. [ABSTRACT FROM AUTHOR]

Lunar exploration is a strategic project in China. The last as well as the most vital step is to build lunar research stations. In order to contribute some experience and ideas to the construction, an inflatable rigid-flexible coupling design was proposed. Additionally, the use and function of each layer will be illustrated fully. Through the simulation analysis of commercial software ABAQUS, the situations of static load mode without the influence of moonquakes as well as the dynamic load mode under the influence of quakes were studied. It shows that the designed stations can perform well in mechanical properties under both conditions. It follows that the design can offer some practical help to the engineering project. [ABSTRACT FROM AUTHOR]

The lightweight and high strength toughness of materials are of great significance for achieving energy-saving, environmental protection, and sustainable development strategies. Particle reinforced aluminum matrix composites, due to their combined performance advantages of reinforcing phase and matrix alloy, can achieve high modulus, high strength, and high heat resistance, and have become one of the focuses of high performance light alloy research and development.AlN reinforced aluminum matrix composites have high degree of microstructure design and can effectively improve the strength and toughness of the Al matrix, which has attracted extensive attention from scholars at home and abroad. The mechanical property progress of AlN reinforced aluminum matrix composites was focused in this paper. Firstly, the effects of preparation methods, interface structure regulation, hybrid strengthening and configuration design on the strength and toughness of AlN reinforced aluminum matrix composites were introduced. Influence of configuration design on the strength and toughening effect of AlN reinforced aluminum matrix composites was illustrated at room temperature and high temperature strengthening, respectively. Then, mechanism of the heterogeneous induced strengthening at room temperature and load transfer strengthening at high temperatures were emphasized. Finally, the new preparation technology, precise microstructure design and strengthening mechanism of heterogeneous configuration of AlN reinforced aluminum matrix composites were prospected.

To meet the in-orbit construction needs of super-large spacecraft for ultra-long rod structures, this paper proposes an innovative on-orbit roll forming method for polyetheretherketone (PEEK)-based rod stock. This method ingeniously integrates temperature gradient control into a continuous deformation surface cavity design to achieve an efficient forming of resin rod components. A parametric model of the forming die cavity was established based on the comprehensive bending and downhill methods, and the boundary conditions for the temperature distribution gradient within the cavity were determined. Through the simulation and analysis of the PEEK rod curling and stitching forming process, the influence of the cavity configuration parameters on the forming load was determined. By constructing a test platform for the roll forming characteristics of resin rod components, the effects of different forming methods, stitching temperatures, and feed rates on forming quality and load were verified, and the main factors affecting the width of the welding zone, the roundness of the rod, and the straightness of the weld were analyzed. Experimental results show that the proposed continuous roll forming scheme can achieve an efficient and continuous forming of resin rod structures. When the length of the member is processed to 300 mm, at a formed rod diameter of 20 mm, by employing a cavity deformation zone length of 210 mm, a cavity clearance of 0.1 mm, a sheet width of 61 mm, a feed rate of 1 mm/s, and a sealing zone temperature setting of 335 °C, optimal rod forming quality can be achieved, characterized by a straightness error of 0.0133 ± 0.005 mm and a roundness error of 0.19 ± 0.07 mm. The proposal of this scheme provides a reliable basis for the continuous manufacturing of rod structures in the on-orbit construction of large space structures in terms of both the scheme and the parameter selection.

Rigid robots have found wide-ranging applications in manufacturing automation, owing to their high loading capacity, high speed, and high precision. Nevertheless, these robots typically feature joint-based drive mechanisms, possessing limited degrees of freedom (DOF), bulky structures, and low manipulability in confined spaces. In contrast, continuum robots, drawing inspiration from biological structures, exhibit characteristics such as high compliance, lightweight designs, and high adaptability to various environments. Among them, cable-driven continuum robots (CDCRs) driven by multiple cables offer advantages like higher dynamic response compared to pneumatic systems and increased working space and higher loading capacity compared to shape memory alloy (SMA) drives. However, CDCRs also exhibit some shortcomings, including complex motion, drive redundancy, challenging modeling, and control difficulties. This study presents a comprehensive analysis and summary of CDCR research progress across four key dimensions: configuration design, kinematics and dynamics modeling, motion planning, and motion control. The objective of this study is to identify common challenges, propose solutions, and unlock the full potential of CDCRs for a broader range of applications. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Materials Engineering / Cailiao Gongcheng is the property of Journal of Materials Engineering Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Systems Engineering & Electronics is the property of Journal of Systems Engineering & Electronics Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

To provide accurate capacity and functionality needed for each demand period (DP), a reconfigurable manufacturing system (RMS) is able to change its configuration with time. For the RMS with multi-part flow line configuration that concurrently produces multiple parts within the same family, the cost and delivery time are dependent on its configuration and relating scheduling for any DP. So far, the study on solution method for the integrated optimisation problem of configuration design and scheduling for RMS is scarce. To efficiently find solutions with tradeoffs between total cost and tardiness, a multi-objective particle swarm optimisation (MoPSO) based on crowding distance and external Pareto solution archive is presented to solve practical-sized problems. The devised encoding and decoding methods along with the particle updating mechanism of MoPSO ensure any particle a feasible solution. The comparison between MoPSO and ε-constraint method versus small-sized cases illustrates the effectiveness of MoPSO. The comparative results between MoPSO and nondominated sorting genetic algorithm II (NSGA-II) against eight problems show that the MoPSO outperforms the NSGA-II in both solution quality and computation efficiency for the integrated optimisation problem. [ABSTRACT FROM AUTHOR]

A reconfigurable manufacturing system (RMS) can provide a customised manufacturing process to complete changes in operational requirements or machine status. The effective development of an RMS is supported by dynamic reconfiguration management that detects errors in the process and explores the reconfiguration strategy. However, existing studies on reconfiguration focus on production while ignoring inspection. In the RMS, a reconfigurable inspection system (RIS) is developed for data-oriented detection of product quality with the minimally sufficient number of inspection machines. We propose a key feature-based method for designing the RIS's configuration to achieve a satisfactory RIS design, which detects different processes and satisfies the inspection requirement for each phase of the RMS's lifecycle. The key features of the RIS (i.e. modularity, integrability, customisation, scalability, convertibility and diagnosability) are identified based on the RMS's detection mechanism. An example of the RMS for a spindle box is presented to validate the method. [ABSTRACT FROM AUTHOR]

A station in the Chinese Baijiu box packaging production line has a height difference between the two production lines due to the workshop layout, and the height difference will increase the defective rate of the Chinese Baijiu box base of the station. Aiming at the problem of high defective rate, a 1R2T parallel mechanism is proposed in this research. Based on the screw theory and screw reciprocity principle, a variety of parallel mechanisms that can meet the needs of the station are synthesized. According to the field working conditions, a 2RPS-RPR parallel mechanism is designed, which can realize the 1R2T function and has three degrees of freedom. The inverse solution analysis and workspace description of the parallel mechanism are carried out, and the three-dimensional model of the parallel mechanism is drawn according to the layout of the production line. The rationality of the mechanism motion is analyzed. It is obtained that the combination of configuration design based on the screw theory and actual working conditions is a very effective theoretical analysis method.

The conceptual design of unmanned aerial vehicles (UAVs) presents significant multidisciplinary challenges requiring the optimization of aerodynamic and structural performance, stealth, and propulsion efficiency. This work addresses these challenges by integrating deep neural networks with a multiobjective genetic algorithm to optimize UAV configurations. The proposed framework enables a comprehensive evaluation of design alternatives by estimating key performance metrics required for different operational requirements. The design process resulted in a significant improvement in computational time over traditional methods by more than three orders of magnitude. The findings illustrate the framework’s capability to optimize UAV designs for a variety of mission scenarios, including specialized tasks such as intelligence, surveillance, and reconnaissance (ISR), combat air patrol (CAP), and Suppression of Enemy Air Defenses (SEAD). This flexibility and adaptability was demonstrated through a case study, showcasing the method’s effectiveness in tailoring UAV configurations to meet specific operational requirements while balancing trade-offs between aerodynamic efficiency, stealth, and structural weight. Additionally, these results underscore the transformative impact of integrating AI into the early stages of the design process, facilitating rapid prototyping and innovation in aerospace engineering. Consequently, the current work demonstrates the potential of AI-driven optimization to revolutionize UAV design by providing a robust and effective tool for solving complex engineering problems.

Reconfigurable transfer lines (RTLs), which are highly responsive to demand fluctuations, have gained increasing attention. This research deals with the line configuration design and balancing problem of RTLs under uncertain demand where line configuration can be changed to satisfy a given demand with minimum cost. It is assumed that the demand of a single product is in interval form. Such RTL is composed of a sequence of workstations and each workstation consists of several identical CNC machining centres. The RTL production capability could be adjusted by adding/removing machines or overtime work. The line configuration and balancing decision is to determine the number of workstations, specify the set-up and the number of machines in each workstation, then assign operations to workstations with various constrains satisfied. Interval optimisation theory is introduced to cope with demand uncertainty. A two-stage optimisation model is developed to handle the primary RTL design and the necessary system reconfiguration. A heuristic algorithm based on greedy randomised adaptive search procedure combined with variable neighbourhood search is given for operation assignment. An industrial case study is carried out and multiple near-optimal solutions are obtained. The feasibility and effectiveness of the proposed method is verified by the comparison of computational experiments. [ABSTRACT FROM AUTHOR]

With the increasing competition in the manufacturing market, reconfigurable manufacturing system (RMS) is gaining more and more attention because it can quickly respond to the changes in the market by adjusting manufacturing resources and organizational structure. Reconfigurable flexible job-shop (RFJS) is one of the main forms of RMS, which is composed of multiple reconfigurable manufacturing cells (RMCs). Each RMC contains several manufacturing equipment which can process a job simultaneously or continuously without multiple clamping. For RMS, both manufacturing resource configuration and production scheduling have direct impacts on its production efficiency, and they are strongly coupled and need to be considered simultaneously. In addition, multi-machine cooperative machining (MCM) has been realized and applied in various manufacturing scenarios with a wide application of intelligent manufacturing equipment such as mechanical arms. However, it is rarely considered in the production plan of RMS. Based on this background, this paper proposes a reconfiguration scheduling problem considering multi-machine cooperation (MCRSP) for RFJSs. Firstly, a multi-phase scheduling method and two manufacturing resource adjustment strategies are designed, and the mathematical model of MCRSP is established with reconfiguration costs and maximum completion time as evaluation indexes. Then, a three-layer coding method is designed, and a Scout and Mutation-based Aquila Optimizer (SMAO) is developed to solve the MCRSP model. In SMAO, the scout bee strategy and gaussian mutation strategy are introduced to improve the exploration ability in later iterations; a new leader selection method is proposed to avoid falling into local optimum prematurely; the balanced mechanism between exploitation and exploration is redesigned to ensure the search efficiency and convergence accuracy. A comparative experiment shows that SMAO contributes 18 optimal values among the 23 standard test functions, demonstrating the enhancement strategies' pertinence and effectiveness. Finally, the calculation and analysis of a practical case show that the proposed MCRSP can significantly improve production efficiency with a limited increase in reconfiguration costs, so it is suitable for practical engineering. [ABSTRACT FROM AUTHOR]

Copyright of Systems Engineering & Electronics is the property of Journal of Systems Engineering & Electronics Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Machine Tool & Hydraulics is the property of Guangzhou Mechanical Engineering Research Institute (GMERI) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Sonic boom suppression is a key technology that must be broken through in the development of a new generation of supersonic civil aircraft. The reasonable design of configuration parameters can make the aircraft have good sonic boom characteristics. In order to break through the bottleneck of evolutionary algorithm in optimizing large-scale design variables, a hierarchical optimization method based on data mining is proposed, and the decision tree (DT) algorithm based data mining is used to extract the design knowledge, obtain the hierarchical information of design variables, and guide the configuration optimization of low sonic boom aircraft. For a low boom supersonic aircraft, five configuration parameters, including sweep angle, aspect ratio, taper ratio, dihedral angle and fuselage slenderness ratio, are selected as design variables to carry out the numerical experiments of hierarchical optimization, and the method is performed with comparison verification with the integrated optimization method. The results show that the hierarchical optimization method can obtain the optimal solution consistent with the integrated optimization method, and the convergence speed of hierarchical optimization method is significantly faster than that of integrated optimization method, and the performance of different optimization processes is more robust.

Rigid origami is a very active branch in the field of origami, which can achieve continuous transformation between two-dimensional and three-dimensional during folding, and there is no strain inside the panel beyond the crease. So it is suitable for a variety of rigid deployable and foldable mechanism. The space deployable and foldable mechanism derived from the rigid origami pattern is characterized by high surface accuracy, large folding ratio, and few degrees of freedom, which can meet the requirements of space engineering for large scale, lightweight and high-precision space folding and unfolding mechanisms. Aiming at the future development tendency, an overview of rigid origami geometry and kinematic fundamentals is provided. The rigid origami typical patterns related to the space folding mechanism are expounded, and the characteristics of various configurations and related research progress are mainly introduced. According to the complexity of the crease, the application and research status of rigid origami for space deployable mechanism is reviewed from different rigid origami patterns. The future development direction and research focus of the space deployable and foldable mechanism based on rigid origami patterns are foreseen from five aspects, ncluding innovative design of configuration, thickness-accommodation design method, dynamic characteristic analysis method, intelligent design method of mechanism, and microgravity unloading method. This research provides a reference for the research and application of large space folding mechanism. [ABSTRACT FROM AUTHOR]

In order to realize stable grasping and dexterous manipulation of irregular objects in unstructured environments, a fully-actuated three-fingered multi-modality dexterous hand with precise perception is developed. To enhance the movement performance of the dexterous hand in 3D space, the axis of the metacarpophalangeal (MCP) joint is perpendicular to the other two joint axes to form the 9-DoF hand mechanism, which effectively increases the grasping modalities of the dexterous hand. Meanwhile, high-precision 6-axis force/torque (F/T) sensors are integrated and embedded in distal interphalangeal (DIP) links and fingertips to improve the perception of the dexterous hand. Finally, the precision experiments on F/T sensors and joint movement with the grasping experiment are carried out to evaluate the performance of the hand. The results show that the force and torque errors of the sensors are less than 1 % and 4 % , the joint movement error of the proposed dexterous hand is less than 1.4 degree. Multi-modality grasping of various objects is performed to show that the high precision and strong grasping capabilities of the proposed dexterous hand. [ABSTRACT FROM AUTHOR]