This paper investigates the configuration design associated with boundary-constrained swarm flying.An analytic swarm configuration is identified to ensure the passive safety between each pair of spacecraft in the radi...This paper investigates the configuration design associated with boundary-constrained swarm flying.An analytic swarm configuration is identified to ensure the passive safety between each pair of spacecraft in the radial-cross-track plane.For the first time,this work derives the explicit configurable spacecraft amount to clarify the configuration's accommodation capacity while considering the maximum inter-spacecraft separation constraint.For larger-scale design problem that involves hundreds of spacecraft,this paper proposes an optimization framework that integrates a Relative Orbit Element(ROE)affine transformation operation and successional convex optimization.The framework establishes a multi-subcluster swarm structure,allowing decoupling the maintenance issues of each subcluster.Compared with previous design methods,it ensures that the computational cost for constraints verification only scales linearly with the swarm size,while also preserving the configuration optimization capacities.Numerical simulations demonstrate that the proposed analytic configuration strictly meets the design constraints.It is also shown that the proposed framework reduces the handled constraint amount by two orders compared with direct optimization,while achieving a remarkable swarm safety enhancement based on the existing analytic configuration.展开更多
Satellite constellation configuration design is a complicated and time-consuming simulation optimization problem. In this paper, a new method called the rapid method for satellite constellation performance calculation...Satellite constellation configuration design is a complicated and time-consuming simulation optimization problem. In this paper, a new method called the rapid method for satellite constellation performance calculation is developed by the Hermite interpolation technique to reduce the computing complication and time. The constellation configuration optimization model is established on the basis of the rapid performance calculation. To reduce the search space and enhance the optimization efficiency, this paper presents a new constellation optimization strategy based on the ordinal optimization (00) theory and expands the algorithm realization for constellation optimization including precise and crude models, ordered performance curves, selection rules and selected subsets. Two experiments about navigation constellation and space based surveillance system (SBSS) are carried out and the analysis of simulation results indicates that the ordinal optimization for satellite constellation configuration design is effective.展开更多
Capture is a key component for on?orbit service and space debris clean. The current research of capture on?orbit focuses on using special capture devices or full?actuated space arms to capture cooperative targets. How...Capture is a key component for on?orbit service and space debris clean. The current research of capture on?orbit focuses on using special capture devices or full?actuated space arms to capture cooperative targets. However, the structures of current capture devices are complex, and both space debris and abandoned spacecraft are non?cooperative targets. To capture non?cooperative targets in space, a lightweight, less driven under?actuated robotic hand is proposed in this paper, which composed by tendon?pulley transmission and double?stage mechanisms, and always driven by only one motor in process of closing finger. Because of the expandability, general grasping model is constructed. The equivalent joint driving forces and general grasping force are analyzed based on the model and the principle of virtual work. Which reveal the relationship among tendon driving force, joint driving forces and grasping force. In order to configure the number of knuckles of finger, a new analysis method which takes the maximum grasping space into account, is proposed. Supposing the maximum grasped object is an envelope circle with diameter of 2.5m. In the condition, a finger grasping maximum envelope circle with different knuckles is modeled. And the finger lengths with corresponding knuckles are calculated out. The finger length which consists of three knuckles is the shortest among under?actuated fingers consists of not more than five knuckles. Finally, the principle prototype and prototype robotic hand which consists of two dingers are designed and assembled. Experiments indicate that the under?actuated robotic hand can satisfy the grasp requirements.展开更多
Configuration design is an essential, creative and decision-making step m parallel manipulator design process, in which modeling and assembly are iterative and trivial. Combined approach with automatic parametric mode...Configuration design is an essential, creative and decision-making step m parallel manipulator design process, in which modeling and assembly are iterative and trivial. Combined approach with automatic parametric modeling and automatic assembly is proposed for parallel manipulator configuration design. The design process and key techniques, such as configuration design, configuration verification, poses calculation of all parts in parallel manipulator, virtual assembly and etc., are discussed and demonstrated by an example. A software package is developed for parallel manipulator configuration design based on the proposed method with Visual C++ and UG/OPEN on Unigraphics.展开更多
The paper studies on case-based reasoning of uncertain product attributes in configuration design of a product family. Interval numbers characterize uncertain product attributes. By interpolating a number of certain v...The paper studies on case-based reasoning of uncertain product attributes in configuration design of a product family. Interval numbers characterize uncertain product attributes. By interpolating a number of certain values randomly to replace interval numbers and making projection pursuit analysis on source cases and target cases of expanded numbers, we can get a projection value in the optimal projection direction. Based on projection value, we can construct a case retrieval model of projection pursuit that can handle coexisting certain and uncertain product attributes. The application examples of chainsaw configuration design show that case retrieval is highly sensitive to reliable results.展开更多
Superheated steam temperature control system is an indispensable part of the unit, its performance and reliability has become an important factor to ensure the safety and economy of the unit. When the superheated stea...Superheated steam temperature control system is an indispensable part of the unit, its performance and reliability has become an important factor to ensure the safety and economy of the unit. When the superheated steam temperature is high, the thermal efficiency of the unit is relatively high. However, when the superheated steam temperature is too high, the metal material of the steam turbine cannot bear it. If the temperature is too low, the efficiency of the unit will be affected. The stability of superheated steam temperature is very important for the safe and economic operation of the unit, so there are higher requirements for its control. In the whole control system of power plant, there are many factors affecting superheated steam temperature, including steam flow disturbance, flue gas flow disturbance and desuperheating water disturbance. The spray desuperheating method is widely used at present, which is beneficial to the safe operation of superheater. Combined with the operation characteristics of the 300MW unit in Diaobingshan power plant, this paper studies and analyzes the superheated steam temperature control strategy, designs a set of control scheme under all working conditions, sets the relevant control parameters, and verifies its effect through simulation. The superheated steam temperature is regulated by two-stage spray desuperheating, and the first stage desuperheating is arranged at the inlet of platen superheater for coarse regulation of steam temperature. The secondary desuperheater is arranged at the inlet of high temperature superheater for fine adjustment. The superheated steam temperature at the outlet of the boiler is maintained at the set value by adjusting the water spray quantity of the primary and secondary superheaters.展开更多
Long-bone fractures are common complaints in orthopedic surgery.In recent years,significant progress has been made in robot-assisted fracture-reduction techniques.As a key medical device for diverse fracture morpholog...Long-bone fractures are common complaints in orthopedic surgery.In recent years,significant progress has been made in robot-assisted fracture-reduction techniques.As a key medical device for diverse fracture morphologies and sites,the design of the reduction robot has a profound impact on the reduction outcomes.However,existing reduction robots have practical limitations and cannot simultaneously satisfy clinical requirements in terms of workspace,force/torque,and structural stiffness.To overcome these problems,we first analyze the potential placement areas and performance requirements of reduction robots according to clinical application scenarios.Subsequently,a 3UPS/S-3P hybrid configuration with decoupled rotational and translational degrees of freedom(DOFs)is proposed,and a kinematic model is derived to achieve the motion characteristics of the remote center of motion(RCM).Furthermore,the structural design of a hybrid reduction robot with an integrated distal clamp and proximal fixator was completed,and a mechanical prototype was constructed.The results of the performance evaluations and static analysis demonstrate that the proposed reduction robot has acceptable workspace,force,and torque performance and excellent structural stiffness.Two clinical case simulations further demonstrated the clinical feasibility of the robot.Finally,preliminary experiments on bone models demonstrated the potential effectiveness of the proposed reduction robot in lower-limb fracture reduction.展开更多
The configuration optimization design of Low Earth Orbit observation mega constellation in complex space environment is a nonlinear problem that is difficult to solve analytically.In this paper,a constellation design ...The configuration optimization design of Low Earth Orbit observation mega constellation in complex space environment is a nonlinear problem that is difficult to solve analytically.In this paper,a constellation design method is proposed,considering satellite imaging width,formation flying of subgroup satellites,and global uniform coverage by payloads.Firstly,a configuration of satellites with the same subsatellite trajectory is proposed,and its orbital analytical expression under J2 perturbation is provided.Then,the relative motion feature points are extracted near the orbit of each satellite,and a group of uniform natural accompanying satellites are set to corresponding points.Afterwards,the orbit parameters of satellite and its companions are set as initial values,and the precise orbits under the High Precision Orbit Propagator model are solved in the neighborhood by using the Nondominated Sort Particle Swarm Optimization algorithm.Finally,the correctness of the configuration design method is verified by numerical simulation.展开更多
The contradiction between manufacturing costs and customer demand of mechatronic products can be balanced by configuration design. The article proposes a customer-oriented configuration model for modular mechatronic p...The contradiction between manufacturing costs and customer demand of mechatronic products can be balanced by configuration design. The article proposes a customer-oriented configuration model for modular mechatronic products which makes up the shortfall in meeting customer needs for the traditional configuration de- sign mode. The elements of the modular mechatronic products configuration model including module, module connection and configuration knowledge are analyzed. And a formal representation method for configuration model elements combining with their characteristics is given. Based on the above research, an abstract configuration model of modular mechatronic products is designed. Finally, an industrial robot is used as an application exam- ple to build a customer-oriented industrial robot configuration model.展开更多
In this work, a novel airframe/propulsion integration design method of the wing-body configuration for hypersonic cruise aircraft is proposed, where the configuration is integrated with inward-turning inlets. With the...In this work, a novel airframe/propulsion integration design method of the wing-body configuration for hypersonic cruise aircraft is proposed, where the configuration is integrated with inward-turning inlets. With the help of this method, the major design concern of balancing the aerodynamic performance against the requirements for efficient propulsion can be well addressed. A novel geometric parametrically modelling method based on a combination of patched class and shape transition(CST) and COONs surface is proposed to represent the configuration, especially a complex configuration with an irregular inlet lip shape. The modelling method enlarges the design space of components on the premise of guaranteeing the configuration integrity via special constraints imposed on the interface across adjacent surfaces. A basic flow inside a cone shaped by a dual-inflection-point generatrix is optimized to generate the inward-turning inlet with improvements of both compression efficiency and flow uniformity. The performance improvement mechanism of this basic flow is the compression velocity variation induced by the variation of the generatrix slope along the flow path. At the design point, numerical simulation results show that the lift-to-drag ratio of the configuration is as high as 5.2 and the inlet works well with a high level of compression efficiency and flow uniformity. The design result also has a good performance on off-design conditions. The achievement of all the design targets turns out that the integration design method proposed in this paper is efficient and practical.展开更多
To improve the power efficiency and optimize the configuration of cold crucible using for continuous melting and directional solidification (DS), based on experimental verification, 3D finite element (FE) models w...To improve the power efficiency and optimize the configuration of cold crucible using for continuous melting and directional solidification (DS), based on experimental verification, 3D finite element (FE) models with various configuration-elements were developed to investigate the magnetic field in cold crucible. Magnetic flux density (B) was measured and calculated under different configuration parameters. These parameters include the inner diameter (D2), the slit width (d), the thickness of crucible wall, the section shape of the slit and the shield ring. The results show that the magnetic flux density in z direction (Bz) both at the slit and at the midpoint of segment will increase with the decrease of D2 or with the increase of the width of the slit and the section area of wedge slit or removing the shield ring. In addition, there is a worst wall thickness that can induce the minimum Bz for a cold crucible with a certain outer diameter.展开更多
An optimal design methodology for the configuration of two rail slider was proposed to get better dynamic performance. The taper length, taper height and the rail width of the reading/writing head are considered as ...An optimal design methodology for the configuration of two rail slider was proposed to get better dynamic performance. The taper length, taper height and the rail width of the reading/writing head are considered as design variables. The complex geometry method is utilized as the search scheme in the optimization process. Optimization results show that the new slider has better dynamic characteristics and is more stable than the original designed slider. The optimization process also demonstrates that the optimum model and optimum method is effective.展开更多
Filter capacitors play an important role in altern-ating current(AC)-line filtering for stabilizing voltage,sup-pressing harmonics,and improving power quality.However,traditional aluminum electrolytic capacitors(AECs)...Filter capacitors play an important role in altern-ating current(AC)-line filtering for stabilizing voltage,sup-pressing harmonics,and improving power quality.However,traditional aluminum electrolytic capacitors(AECs)suffer from a large size,short lifespan,low power density,and poor reliability,which limits their use.In contrast,ultrafast supercapacitors(SCs)are ideal for replacing commercial AECs because of their extremely high power densities,fast charging and discharging,and excellent high-frequency re-sponse.We review the design principles and key parameters for ultrafast supercapacitors and summarize research pro-gress in recent years from the aspects of electrode materials,electrolytes,and device configurations.The preparation,structures,and frequency response performance of electrode materials mainly consisting of carbon materials such as graphene and carbon nanotubes,conductive polymers,and transition metal compounds,are focused on.Finally,future research directions for ultrafast SCs are suggested.展开更多
This article presents a parameterized configuration modeling approach to develop a 6 degrees of freedom (DOF) rigid-body model for air-breathing hypersonic vehicle (AHV). The modeling process involves the paramete...This article presents a parameterized configuration modeling approach to develop a 6 degrees of freedom (DOF) rigid-body model for air-breathing hypersonic vehicle (AHV). The modeling process involves the parameterized configuration design, inviscous hypersonic aerodynamic force calculation and scramjet engine modeling. The parameters are designed for airframe-propulsion integration configuration, the aerodynamic force calculation is based on engineering experimental methods, and the engine model is acquired from gas dynamics and quasi-one dimensional combustor calculations. Multivariate fitting is used to obtain analytical equations for aerodynamic force and thrust. Furthermore, the fitting accuracy is evaluated by relative error (RE). Trim results show that the model can be applied to the investigation of control method for AHV during the cruise phase. The modeling process integrates several disciplines such as configuration design, aerodynamic calculation, scramjet modeling and control method. Therefore the modeling method makes it possible to conduct AHV aerodynamics/propulsion/control integration design.展开更多
In implementing mass customization, how to respond rapidly to customers’ requirements is a key problem. Configuration design is considered effective in early stage of product design. This paper studies a configuratio...In implementing mass customization, how to respond rapidly to customers’ requirements is a key problem. Configuration design is considered effective in early stage of product design. This paper studies a configuration method based on constraints and fuzzy decision for product family. The configuration method is evolved from constraint based product configuration. It employs fuzzy optimum selection in the reasoning process, which can select similar components when customers’ requirements can not be met precisely. In the configurator, product family is represented with GBOM(Generic Bill Of Material) and ACL(Article Characteristic List). Every node of GBOM has an ACL to list all instances of a component family. Constraints are attached to every node, which involves variable definition and constraints definition. In the reasoning process, constraint satisfaction and fuzzy optimum selection interact to search optimum solution. A prototype is developted to demonstrate how to run the configurator. The paper ends with a discussion of advantages, future work of the configuration method.展开更多
On the basis of researching on requirement product configuration in mass customization, the concept of product family requirement class (PFRC) and requirement-matching template are put forward. A case-based requirem...On the basis of researching on requirement product configuration in mass customization, the concept of product family requirement class (PFRC) and requirement-matching template are put forward. A case-based requirement product configuration (CB-RPC) model and corresponding requirement product model are established. The result of requirement product configuration is obtained by using the method of two-level similar matching. In addition, the effect of the method on requirement responding is analyzed. Finally, the model and the method given are applied in elevator industry, and have improved the enterorise's ability of rapid responding to customer's reouirements.展开更多
Today's manufacturing cnvironmem forces manufacturing companies to make as many product variations as possible at affordable costs within a short time. Mass customisation is one of most important technologies for com...Today's manufacturing cnvironmem forces manufacturing companies to make as many product variations as possible at affordable costs within a short time. Mass customisation is one of most important technologies for companies to achieve their objectives. Efforts to mass customisation should be made on two aspects: (1) To modularize products and make them as less differences as possible; (2) To design manufacturing resources and make them provide as many processes variations as possible. This paper reports our recent work on aspect (2), i.e. how to design a reconfignrable manufacturing system (RMS) so that it can be competent to accomplish various processes optimally; Reconfignrable robot system (RRS) is taken as an example. RMS design involves architecture design and configuration design, and configuration design is further divided in design analysis and design synthesis. Axiomatic design theory (ADT) is applied to architecture design, the features and issues of RRS configuration design are discussed, automatic modelling method is developed for design analysis, and concurrent design methodology is presented for design synthesis.展开更多
The current research of configurable product design mainly focuses on how to convert a predefined set of components into a valid set of product structures. With the scale and complexity of configurable products increa...The current research of configurable product design mainly focuses on how to convert a predefined set of components into a valid set of product structures. With the scale and complexity of configurable products increasing, the interdependencies between customer demands and product structures grow up as well. The result is that existing product structures fails to satisfy the individual customer requirements and hence product variants are needed. This paper is aimed to build a bridge between customer demands and product structures in order to make demand-driven fast response design feasible. First of all, multi-hierarchical models of configurable product design are established with customer demand model, technical requirement model and product structure model. Then, the transition of multi-hierarchical models among customer demand model, technical requirement model and product structure model is solved with fuzzy analytic hierarchy process (FAHP) and the algorithm of multi-level matching. Finally, optimal structure according to the customer demands is obtained with the calculation of Euclidean distance and similarity of some cases. In practice, the configuration design of a clamping unit of injection molding machine successfully performs an optimal search strategy for the product variants with reasonable satisfaction to individual customer demands. The proposed method can automatically generate a configuration design with better alternatives for each product structures, and shorten the time of finding the configuration of a product.展开更多
This paper puts forward a design idea for blended wing body(BWB).The idea is described as that cruise point,maximum lift to drag point and pitch trim point are in the same flight attitude.According to this design id...This paper puts forward a design idea for blended wing body(BWB).The idea is described as that cruise point,maximum lift to drag point and pitch trim point are in the same flight attitude.According to this design idea,design objectives and constraints are defined.By applying low and high fidelity aerodynamic analysis tools,BWB aerodynamic design methodology is established by the combination of optimization design and inverse design methods.High lift to drag ratio,pitch trim and acceptable buffet margin can be achieved by this design methodology.For 300-passenger BWB configuration based on static stability design,as compared with initial configuration,the maximum lift to drag ratio and pitch trim are achieved at cruise condition,zero lift pitching moment is positive,and buffet characteristics is well.Fuel burn of 300-passenger BWB configuration is also significantly reduced as compared with conventional civil transports.Because aerodynamic design is carried out under the constraints of BWB design requirements,the design configuration fulfills the demands for interior layout and provides a solid foundation for continuous work.展开更多
A novel configuration performance prediction approach with combination of principal component analysis(PCA) and support vector machine(SVM) was proposed.This method can estimate the performance parameter values of a n...A novel configuration performance prediction approach with combination of principal component analysis(PCA) and support vector machine(SVM) was proposed.This method can estimate the performance parameter values of a newly configured product through soft computing technique instead of practical test experiments,which helps to evaluate whether or not the product variant can satisfy the customers' individual requirements.The PCA technique was used to reduce and orthogonalize the module parameters that affect the product performance.Then,these extracted features were used as new input variables in SVM model to mine knowledge from the limited existing product data.The performance values of a newly configured product can be predicted by means of the trained SVM models.This PCA-SVM method can ensure that the performance prediction is executed rapidly and accurately,even under the small sample conditions.The applicability of the proposed method was verified on a family of plate electrostatic precipitators.展开更多
基金co-supported by the National Natural Science Foundation of China(Nos.52272408,U21B2008)the Guangdong Basic and Applied Basic Research Foundation,China(No.2023B1515120018)。
文摘This paper investigates the configuration design associated with boundary-constrained swarm flying.An analytic swarm configuration is identified to ensure the passive safety between each pair of spacecraft in the radial-cross-track plane.For the first time,this work derives the explicit configurable spacecraft amount to clarify the configuration's accommodation capacity while considering the maximum inter-spacecraft separation constraint.For larger-scale design problem that involves hundreds of spacecraft,this paper proposes an optimization framework that integrates a Relative Orbit Element(ROE)affine transformation operation and successional convex optimization.The framework establishes a multi-subcluster swarm structure,allowing decoupling the maintenance issues of each subcluster.Compared with previous design methods,it ensures that the computational cost for constraints verification only scales linearly with the swarm size,while also preserving the configuration optimization capacities.Numerical simulations demonstrate that the proposed analytic configuration strictly meets the design constraints.It is also shown that the proposed framework reduces the handled constraint amount by two orders compared with direct optimization,while achieving a remarkable swarm safety enhancement based on the existing analytic configuration.
文摘Satellite constellation configuration design is a complicated and time-consuming simulation optimization problem. In this paper, a new method called the rapid method for satellite constellation performance calculation is developed by the Hermite interpolation technique to reduce the computing complication and time. The constellation configuration optimization model is established on the basis of the rapid performance calculation. To reduce the search space and enhance the optimization efficiency, this paper presents a new constellation optimization strategy based on the ordinal optimization (00) theory and expands the algorithm realization for constellation optimization including precise and crude models, ordered performance curves, selection rules and selected subsets. Two experiments about navigation constellation and space based surveillance system (SBSS) are carried out and the analysis of simulation results indicates that the ordinal optimization for satellite constellation configuration design is effective.
基金Supported by Joint Funds of National Natural Science Foundation of China(Grant No.U1613201)Shenzhen Research Funds(JCYJ20170413104438332)
文摘Capture is a key component for on?orbit service and space debris clean. The current research of capture on?orbit focuses on using special capture devices or full?actuated space arms to capture cooperative targets. However, the structures of current capture devices are complex, and both space debris and abandoned spacecraft are non?cooperative targets. To capture non?cooperative targets in space, a lightweight, less driven under?actuated robotic hand is proposed in this paper, which composed by tendon?pulley transmission and double?stage mechanisms, and always driven by only one motor in process of closing finger. Because of the expandability, general grasping model is constructed. The equivalent joint driving forces and general grasping force are analyzed based on the model and the principle of virtual work. Which reveal the relationship among tendon driving force, joint driving forces and grasping force. In order to configure the number of knuckles of finger, a new analysis method which takes the maximum grasping space into account, is proposed. Supposing the maximum grasped object is an envelope circle with diameter of 2.5m. In the condition, a finger grasping maximum envelope circle with different knuckles is modeled. And the finger lengths with corresponding knuckles are calculated out. The finger length which consists of three knuckles is the shortest among under?actuated fingers consists of not more than five knuckles. Finally, the principle prototype and prototype robotic hand which consists of two dingers are designed and assembled. Experiments indicate that the under?actuated robotic hand can satisfy the grasp requirements.
文摘Configuration design is an essential, creative and decision-making step m parallel manipulator design process, in which modeling and assembly are iterative and trivial. Combined approach with automatic parametric modeling and automatic assembly is proposed for parallel manipulator configuration design. The design process and key techniques, such as configuration design, configuration verification, poses calculation of all parts in parallel manipulator, virtual assembly and etc., are discussed and demonstrated by an example. A software package is developed for parallel manipulator configuration design based on the proposed method with Visual C++ and UG/OPEN on Unigraphics.
文摘The paper studies on case-based reasoning of uncertain product attributes in configuration design of a product family. Interval numbers characterize uncertain product attributes. By interpolating a number of certain values randomly to replace interval numbers and making projection pursuit analysis on source cases and target cases of expanded numbers, we can get a projection value in the optimal projection direction. Based on projection value, we can construct a case retrieval model of projection pursuit that can handle coexisting certain and uncertain product attributes. The application examples of chainsaw configuration design show that case retrieval is highly sensitive to reliable results.
文摘Superheated steam temperature control system is an indispensable part of the unit, its performance and reliability has become an important factor to ensure the safety and economy of the unit. When the superheated steam temperature is high, the thermal efficiency of the unit is relatively high. However, when the superheated steam temperature is too high, the metal material of the steam turbine cannot bear it. If the temperature is too low, the efficiency of the unit will be affected. The stability of superheated steam temperature is very important for the safe and economic operation of the unit, so there are higher requirements for its control. In the whole control system of power plant, there are many factors affecting superheated steam temperature, including steam flow disturbance, flue gas flow disturbance and desuperheating water disturbance. The spray desuperheating method is widely used at present, which is beneficial to the safe operation of superheater. Combined with the operation characteristics of the 300MW unit in Diaobingshan power plant, this paper studies and analyzes the superheated steam temperature control strategy, designs a set of control scheme under all working conditions, sets the relevant control parameters, and verifies its effect through simulation. The superheated steam temperature is regulated by two-stage spray desuperheating, and the first stage desuperheating is arranged at the inlet of platen superheater for coarse regulation of steam temperature. The secondary desuperheater is arranged at the inlet of high temperature superheater for fine adjustment. The superheated steam temperature at the outlet of the boiler is maintained at the set value by adjusting the water spray quantity of the primary and secondary superheaters.
基金Supported by National Natural Science Foundation of China(Grant Nos.52405001,52175001,62373010,82472537)China Postdoctoral Science Foundation(Grant No.2024M760166)+2 种基金Postdoctoral Fellowship Program of CPSF(Grant No.GZC20230186)Shenzhen Municipal Science,Technology,and Innovation Commission(Grant No.SGDX20220530111005036)Beijing Natural Science Foundation(Grant Nos.3222002,3232004,L222061).
文摘Long-bone fractures are common complaints in orthopedic surgery.In recent years,significant progress has been made in robot-assisted fracture-reduction techniques.As a key medical device for diverse fracture morphologies and sites,the design of the reduction robot has a profound impact on the reduction outcomes.However,existing reduction robots have practical limitations and cannot simultaneously satisfy clinical requirements in terms of workspace,force/torque,and structural stiffness.To overcome these problems,we first analyze the potential placement areas and performance requirements of reduction robots according to clinical application scenarios.Subsequently,a 3UPS/S-3P hybrid configuration with decoupled rotational and translational degrees of freedom(DOFs)is proposed,and a kinematic model is derived to achieve the motion characteristics of the remote center of motion(RCM).Furthermore,the structural design of a hybrid reduction robot with an integrated distal clamp and proximal fixator was completed,and a mechanical prototype was constructed.The results of the performance evaluations and static analysis demonstrate that the proposed reduction robot has acceptable workspace,force,and torque performance and excellent structural stiffness.Two clinical case simulations further demonstrated the clinical feasibility of the robot.Finally,preliminary experiments on bone models demonstrated the potential effectiveness of the proposed reduction robot in lower-limb fracture reduction.
基金supported in part by the Fundamental Research Funds for the Central Universities(No.3072022JC0202).
文摘The configuration optimization design of Low Earth Orbit observation mega constellation in complex space environment is a nonlinear problem that is difficult to solve analytically.In this paper,a constellation design method is proposed,considering satellite imaging width,formation flying of subgroup satellites,and global uniform coverage by payloads.Firstly,a configuration of satellites with the same subsatellite trajectory is proposed,and its orbital analytical expression under J2 perturbation is provided.Then,the relative motion feature points are extracted near the orbit of each satellite,and a group of uniform natural accompanying satellites are set to corresponding points.Afterwards,the orbit parameters of satellite and its companions are set as initial values,and the precise orbits under the High Precision Orbit Propagator model are solved in the neighborhood by using the Nondominated Sort Particle Swarm Optimization algorithm.Finally,the correctness of the configuration design method is verified by numerical simulation.
基金supported by Graduate Starting Seed Fund of Northwestern Polytechnical University
文摘The contradiction between manufacturing costs and customer demand of mechatronic products can be balanced by configuration design. The article proposes a customer-oriented configuration model for modular mechatronic products which makes up the shortfall in meeting customer needs for the traditional configuration de- sign mode. The elements of the modular mechatronic products configuration model including module, module connection and configuration knowledge are analyzed. And a formal representation method for configuration model elements combining with their characteristics is given. Based on the above research, an abstract configuration model of modular mechatronic products is designed. Finally, an industrial robot is used as an application exam- ple to build a customer-oriented industrial robot configuration model.
基金supported by the ‘‘111" Project of China (No. B17037)
文摘In this work, a novel airframe/propulsion integration design method of the wing-body configuration for hypersonic cruise aircraft is proposed, where the configuration is integrated with inward-turning inlets. With the help of this method, the major design concern of balancing the aerodynamic performance against the requirements for efficient propulsion can be well addressed. A novel geometric parametrically modelling method based on a combination of patched class and shape transition(CST) and COONs surface is proposed to represent the configuration, especially a complex configuration with an irregular inlet lip shape. The modelling method enlarges the design space of components on the premise of guaranteeing the configuration integrity via special constraints imposed on the interface across adjacent surfaces. A basic flow inside a cone shaped by a dual-inflection-point generatrix is optimized to generate the inward-turning inlet with improvements of both compression efficiency and flow uniformity. The performance improvement mechanism of this basic flow is the compression velocity variation induced by the variation of the generatrix slope along the flow path. At the design point, numerical simulation results show that the lift-to-drag ratio of the configuration is as high as 5.2 and the inlet works well with a high level of compression efficiency and flow uniformity. The design result also has a good performance on off-design conditions. The achievement of all the design targets turns out that the integration design method proposed in this paper is efficient and practical.
基金Project (2011CB605504) supported by the National Basic Research Program of China
文摘To improve the power efficiency and optimize the configuration of cold crucible using for continuous melting and directional solidification (DS), based on experimental verification, 3D finite element (FE) models with various configuration-elements were developed to investigate the magnetic field in cold crucible. Magnetic flux density (B) was measured and calculated under different configuration parameters. These parameters include the inner diameter (D2), the slit width (d), the thickness of crucible wall, the section shape of the slit and the shield ring. The results show that the magnetic flux density in z direction (Bz) both at the slit and at the midpoint of segment will increase with the decrease of D2 or with the increase of the width of the slit and the section area of wedge slit or removing the shield ring. In addition, there is a worst wall thickness that can induce the minimum Bz for a cold crucible with a certain outer diameter.
文摘An optimal design methodology for the configuration of two rail slider was proposed to get better dynamic performance. The taper length, taper height and the rail width of the reading/writing head are considered as design variables. The complex geometry method is utilized as the search scheme in the optimization process. Optimization results show that the new slider has better dynamic characteristics and is more stable than the original designed slider. The optimization process also demonstrates that the optimum model and optimum method is effective.
文摘Filter capacitors play an important role in altern-ating current(AC)-line filtering for stabilizing voltage,sup-pressing harmonics,and improving power quality.However,traditional aluminum electrolytic capacitors(AECs)suffer from a large size,short lifespan,low power density,and poor reliability,which limits their use.In contrast,ultrafast supercapacitors(SCs)are ideal for replacing commercial AECs because of their extremely high power densities,fast charging and discharging,and excellent high-frequency re-sponse.We review the design principles and key parameters for ultrafast supercapacitors and summarize research pro-gress in recent years from the aspects of electrode materials,electrolytes,and device configurations.The preparation,structures,and frequency response performance of electrode materials mainly consisting of carbon materials such as graphene and carbon nanotubes,conductive polymers,and transition metal compounds,are focused on.Finally,future research directions for ultrafast SCs are suggested.
基金Aeronautical Science Foundation of China (2008ZA51002)
文摘This article presents a parameterized configuration modeling approach to develop a 6 degrees of freedom (DOF) rigid-body model for air-breathing hypersonic vehicle (AHV). The modeling process involves the parameterized configuration design, inviscous hypersonic aerodynamic force calculation and scramjet engine modeling. The parameters are designed for airframe-propulsion integration configuration, the aerodynamic force calculation is based on engineering experimental methods, and the engine model is acquired from gas dynamics and quasi-one dimensional combustor calculations. Multivariate fitting is used to obtain analytical equations for aerodynamic force and thrust. Furthermore, the fitting accuracy is evaluated by relative error (RE). Trim results show that the model can be applied to the investigation of control method for AHV during the cruise phase. The modeling process integrates several disciplines such as configuration design, aerodynamic calculation, scramjet modeling and control method. Therefore the modeling method makes it possible to conduct AHV aerodynamics/propulsion/control integration design.
文摘In implementing mass customization, how to respond rapidly to customers’ requirements is a key problem. Configuration design is considered effective in early stage of product design. This paper studies a configuration method based on constraints and fuzzy decision for product family. The configuration method is evolved from constraint based product configuration. It employs fuzzy optimum selection in the reasoning process, which can select similar components when customers’ requirements can not be met precisely. In the configurator, product family is represented with GBOM(Generic Bill Of Material) and ACL(Article Characteristic List). Every node of GBOM has an ACL to list all instances of a component family. Constraints are attached to every node, which involves variable definition and constraints definition. In the reasoning process, constraint satisfaction and fuzzy optimum selection interact to search optimum solution. A prototype is developted to demonstrate how to run the configurator. The paper ends with a discussion of advantages, future work of the configuration method.
基金This project is supported by National Basic Research Program of China (973 Program, No.2004CB719402)National Natural Science Foundation of China(No.50475072, No.50275133)National Hi-tech Research and Development Program of China(863 Program, No.2003-AA411320).
文摘On the basis of researching on requirement product configuration in mass customization, the concept of product family requirement class (PFRC) and requirement-matching template are put forward. A case-based requirement product configuration (CB-RPC) model and corresponding requirement product model are established. The result of requirement product configuration is obtained by using the method of two-level similar matching. In addition, the effect of the method on requirement responding is analyzed. Finally, the model and the method given are applied in elevator industry, and have improved the enterorise's ability of rapid responding to customer's reouirements.
文摘Today's manufacturing cnvironmem forces manufacturing companies to make as many product variations as possible at affordable costs within a short time. Mass customisation is one of most important technologies for companies to achieve their objectives. Efforts to mass customisation should be made on two aspects: (1) To modularize products and make them as less differences as possible; (2) To design manufacturing resources and make them provide as many processes variations as possible. This paper reports our recent work on aspect (2), i.e. how to design a reconfignrable manufacturing system (RMS) so that it can be competent to accomplish various processes optimally; Reconfignrable robot system (RRS) is taken as an example. RMS design involves architecture design and configuration design, and configuration design is further divided in design analysis and design synthesis. Axiomatic design theory (ADT) is applied to architecture design, the features and issues of RRS configuration design are discussed, automatic modelling method is developed for design analysis, and concurrent design methodology is presented for design synthesis.
基金supported by National Natural Science Foundation of China(Grant Nos. 51205350, 51275459)National Science and Technology Major Project of China(Grant No. 2012ZX04010-011)Postdoctoral Research Foundation of Zhejiang Province(Grant No.Bsh1201019)
文摘The current research of configurable product design mainly focuses on how to convert a predefined set of components into a valid set of product structures. With the scale and complexity of configurable products increasing, the interdependencies between customer demands and product structures grow up as well. The result is that existing product structures fails to satisfy the individual customer requirements and hence product variants are needed. This paper is aimed to build a bridge between customer demands and product structures in order to make demand-driven fast response design feasible. First of all, multi-hierarchical models of configurable product design are established with customer demand model, technical requirement model and product structure model. Then, the transition of multi-hierarchical models among customer demand model, technical requirement model and product structure model is solved with fuzzy analytic hierarchy process (FAHP) and the algorithm of multi-level matching. Finally, optimal structure according to the customer demands is obtained with the calculation of Euclidean distance and similarity of some cases. In practice, the configuration design of a clamping unit of injection molding machine successfully performs an optimal search strategy for the product variants with reasonable satisfaction to individual customer demands. The proposed method can automatically generate a configuration design with better alternatives for each product structures, and shorten the time of finding the configuration of a product.
文摘This paper puts forward a design idea for blended wing body(BWB).The idea is described as that cruise point,maximum lift to drag point and pitch trim point are in the same flight attitude.According to this design idea,design objectives and constraints are defined.By applying low and high fidelity aerodynamic analysis tools,BWB aerodynamic design methodology is established by the combination of optimization design and inverse design methods.High lift to drag ratio,pitch trim and acceptable buffet margin can be achieved by this design methodology.For 300-passenger BWB configuration based on static stability design,as compared with initial configuration,the maximum lift to drag ratio and pitch trim are achieved at cruise condition,zero lift pitching moment is positive,and buffet characteristics is well.Fuel burn of 300-passenger BWB configuration is also significantly reduced as compared with conventional civil transports.Because aerodynamic design is carried out under the constraints of BWB design requirements,the design configuration fulfills the demands for interior layout and provides a solid foundation for continuous work.
基金Project(9140A18010210KG01) supported by the Departmental Pre-Research Fund of China
文摘A novel configuration performance prediction approach with combination of principal component analysis(PCA) and support vector machine(SVM) was proposed.This method can estimate the performance parameter values of a newly configured product through soft computing technique instead of practical test experiments,which helps to evaluate whether or not the product variant can satisfy the customers' individual requirements.The PCA technique was used to reduce and orthogonalize the module parameters that affect the product performance.Then,these extracted features were used as new input variables in SVM model to mine knowledge from the limited existing product data.The performance values of a newly configured product can be predicted by means of the trained SVM models.This PCA-SVM method can ensure that the performance prediction is executed rapidly and accurately,even under the small sample conditions.The applicability of the proposed method was verified on a family of plate electrostatic precipitators.