Configuration Design Method Research Articles

A comprehensive design pipeline for FCEV powertrain configuration considering the evolutionary development process and extreme economic performance

Due to stringent emission regulations, the zero-emission hydrogen fuel cell electric vehicles (FCEVs) are gaining significant attention, but their slow power response requires careful selection of auxiliary energy sources and power systems to optimize energy efficiency. This paper presents a comprehensive design pipeline for the FCEV powertrain, encompassing methods for powertrain configuration design, feasible domain design for component parameters, and parameter matching. Initially, a powertrain configuration design method based on evolutionary game theory is introduced, forecasting trends in energy-efficient powertrain configurations using a dynamic cost function that adjusts based on the proportions of different configurations. Next, a feasible domain design method is developed to establish fixed constraints on component parameters, ensuring a fair balance between performance needs and overall costs, including development and lifecycle expenses associated with the powertrain configuration. Subsequently, dynamic programming (DP) is used for parameter matching, assessing the utmost energy-saving potential. The cost function in this method incorporates the degradation cost of powertrain components, underscoring the economic performance of the target FCEV over its lifespan. Finally, simulation assessments indicate that the proposed design pipeline effectively identifies the optimal powertrain configuration for FCEVs, endowing each possible configuration with exceptional economic efficiency across different component parameters.

A configuration design approach to the capacitive six-axis force/torque sensor utilizing the compliant parallel mechanism

The configuration of capacitive six-axis force/torque (F/T) sensors significantly impacts their performance, and there are few studies on the configuration design method of the sensor. By analyzing the signal conversion model of the sensor, this paper proposes that the key to obtaining a reasonable configuration is that the configuration can easily achieve sensitivity isotropy. To achieve sensitivity isotropy, the six-degree-of-freedom sensitive part must be available. The compliant parallel mechanism is easier to meet this requirement. Based on the position and orientation characteristic (POC) set theory, the flexure building blocks applicable to compliant sensitive part configurations are analyzed, and we investigate a methodology for synthesizing compliant parallel sensor configurations that satisfy sensitivity isotropy. The results show that the precision is 0.66%FS in the physical prototype experiment, the fabricated sensor has good performance. The proposed configuration design methodology proposed can effectively guide the design of the capacitive six-axis F/T sensor.

A Modular Robotic Arm Configuration Design Method Based on Double DQN with Prioritized Experience Replay

Abstract: The modular robotic arms can achieve desired performances in different scenarios through the combination of various modules, and concurrently hold the potential to exhibit geometric symmetry and uniform mass symmetry. Therefore, selecting the appropriate combination of modules is crucial for realizing the functions of the robotic arm and ensuring the elegance of the system. To this end, this paper proposes a double deep Q-network (DDQN)-based configuration design algorithm for modular robotic arms, which aims to find the optimal configuration under different tasks. First, a library of small modules of collaborative robotic arms consisting of multiple tandem robotic arms is constructed. These modules are described in a standard format that can be directly imported into the software for simulation, providing greater convenience and flexibility in the development of modular robotic arms. Subsequently, the DDQN design framework for module selection is established to obtain the optimal robotic arm configuration. The proposed method could deal with the overestimation problem in the traditional deep Q-network (DQN) method and improve the estimation accuracy of the value function for each module. In addition, the experience replay mechanism is improved based on the SumTree technique, which enables the algorithm to make effective use of historical experience and prevents the algorithm from falling into local optimal solutions. Finally, comparative experiments are carried out on the PyBullet simulation platform to verify the effectiveness and superiority of the configuration design method developed in the paper. The simulation results show that the proposed DDQN-based method with experience replay mechanism has higher search efficiency and accuracy compared to the traditional DQN scheme.

Intelligent design of reconfigurable flexible assembly fixture for aircraft panels based on smart composite jig model and knowledge graph

The current demand for aircraft panel assembly fixtures necessitates agile manufacturing solutions. Traditional welding fixtures struggle to meet diverse panel types, high quantities, and short manufacturing cycles. Conversely, reconfigurable flexible assembly fixtures offer universality, efficiency and ease of maintenance but heavily rely on designers' experience, hindering knowledge reuse. Existing research on computer-aided fixture design (CAFD) primarily addresses specialized fixtures, neglecting reconfigurable flexible ones, lacking fixture design knowledge systems. Aiming at the above problems, the study proposes an intelligent design method for the reconfigurable flexible assembly fixture for aircraft panels based on the smart composite jig model (SCJM) and knowledge graph (KG). Firstly, based on the SCJM of the aircraft panel type assembly fixture (PSCJM), a configuration design method is proposed to carry out the multi-level design of reconfigurable assembly fixture to instantiate PSCJM containing fixture configuration rules and a module library based on model definition (MBD). Then, a knowledge retrieval method is proposed to search the suitable fixture design knowledge based on KG, assisting designers in achieving the flexible design of aircraft panel reconfigurable assembly fixtures. Finally, practical engineering design validation confirms the method's feasibility and effectiveness in obtaining the reconfigurable flexible assembly fixture design scheme for aircraft panels.

Toward a design methodology for configuring assistive wearables

AbstractWearable devices have some shared characteristics. They should conform to the wearer's size and shape, not interfere with desired activities, perform intended functions, be easily usable and comfortable, among others. Due to these shared characteristics, a common design methodology should be possible for designing wearables that assists designers in taking a systematic approach. We propose a configuration design method for wearables and sketch its elements. An example of a family of passive exoskeleton suits that assists with walking is presented to illustrate the configuration design process.

Design, analysis, and ground deployment test of space deployable mast based on double-layer deployable unit

The space deployable mast has been successfully applied to space equipment such as solar sails and space telescopes. At present, the deployable units of the space deployable mast mostly adopt the configurations of deployable units of FAST (Folding Articulated Square Truss), HIMAT, and ADAM (Able Deployable Articulated Mast). The configuration of the deployable unit is relatively few. Besides, there is a lack of ground micro-gravity environment simulation test devices for space deployable masts. This paper proposes the space deployable mast based on the double-layer deployable unit. Firstly, the configuration design method of the double-layer deployable unit based on the screw theory has been carried out. Three double-layer hybrid mechanisms serving as the basic units of the deployable mast have been obtained. Then, the kinematic and dynamic models of deployment of the space deployable mast have been established. And the deployment simulation based on MATLAB and Simscape has been performed. Furthermore, modal and static simulations have been performed to obtain the fundamental frequencies and maximum deformation displacements of the deployable masts consisting of 1, 2, 4, 8, and 12 units with and without cables. Finally, the ground test device has been developed to carry out the ground deployment test of the space deployable mast in the ground micro-gravity environment. It has been found that the ground test device could achieve the micro-gravity simulation level of 90.5%.

Aerodynamic/control integrated optimization method for unpowered high-speed vehicle configuration design

The unpowered high-speed vehicle experiences a significant coupling between the disciplines of aerodynamics and control due to its characteristics of high flight speed and extensive maneuverability within large airspace. The conventional aircraft conceptual design process follows a sequential design approach, and there is an artificial separation between the disciplines of aerodynamics and control, neglecting the coupling effects arising from their interaction. As a result, this design process often requires extensive iterations over long periods when applied to high-speed vehicles, and may not be able to effectively achieve the desired design objectives. To enhance the overall performance and design efficiency of high-speed vehicles, this study integrates the concept of Active Control Technology (ACT) from modern aircraft into the philosophy of aerodynamic/control integrated optimization. Two integrated optimization strategies, with differences in coupling granularity, have been developed. Subsequently, these strategies are put into action on a biconical vehicle that operates at Mach 5. The results reveal that the comprehensive performance of the synthesis optimal model derived from the aerodynamic/control integrated optimization strategy is improved by 31.76% and 28.29% respectively compared to the base model under high-speed conditions, demonstrating the feasibility and effectiveness of the method and optimization strategies employed. Moreover, in comparison to the single-stage strategy, the multi-stage strategy takes into deeper consideration the impact of control capacity. As a result, the control performance of the synthesis optimal model derived from the multi-stage strategy improves by 13.99%, whereas the single-stage strategy only achieves a 5.79% improvement. This method enables a fruitful interaction between aerodynamic configuration design and control system design, leading to enhanced overall performance and design efficiency. Furthermore, it improves the controllability of high-speed vehicles, mitigating the risk of mission failure resulting from an ineffective control system.

Geometrical design method of Walker constellation in non-terrestrial network

To meet the requirement of mega low earth orbit (LEO) constellation design in non-terrestrial network (NTN), a geometric configuration design method of Walker constellation applicable to arbitrary latitude range coverage multiple and satellite quantity scale is proposed. First, a Walker configuration representation based on the streets of coverage (SoC) characteristic parameters is proposed. Then, satellite quantity required for coverage and the SoC parameters are estimated by calculating the width and adjacent spacing of SoC, which can improve the enumeration efficiency. Finally, by adjusting the phase and quantity of the satellite on the SoC, the constellation configuration with optimal comprehensive performances is selected from multiple groups of results. To demonstrate the effectiveness of the proposed design method, the performance comparisons among the existing mega LEO constellation systems are conducted. Compared with the existing configurations, the configuration calculated by the proposed method can efficiently reduce the satellite quantity required for coverage by about 20%, and can also satisfy the comprehensive demands including coverage performance, inter-satellite link, configuration redundancy and collision avoidance by reasonably selecting configuration parameters.

Configuration Design and Verification of Shear Compliant Border in Space Membrane Structure.

To solve the non-uniformity of stress in space membrane structure and the lack of shear compliant border configuration design method, shear compliant borders are designed, optimized, and verified in terms of configuration. Firstly, an orthotropic model of the borders is built by combining Hill and Christensen-Lo composite material models. Secondly, a finite element form-finding method is put forward by establishing rectangular and cylindrical coordinates in different areas. The configuration of borders is obtained and the influence of the borders on the edge of the membrane is 0.23%, which means that the borders are compatible with the existing tensegrity systems, especially the tensioning components and the cable sleeves. Thirdly, simulation verifies that borders can cut the spread of shear stress and improve the stress uniformity in membrane structure. The maximum stress in the membrane effective area is decreased by 35.6% and the stress uniformity is improved by 30.5%. Finally, a membrane extension experiment is committed to compare the flatness of membrane surface under shear stress with and without shear compliant borders. The borders decrease the increment speed of flatness by 58.1%, which verifies the amelioration of stress uniformity. The shear compliant border configuration design method provides a reference for space membrane structure stress-uniform design.

A novel method to build knowledge graph models for the configuration and operation design of smart and connected industrial products

Abstract Smart and connected industrial products (SCIPs), characterized by their capabilities of self-monitoring, environment awareness, machine–machine/machine–human communication and collaboration, intelligent decision-making, etc., have become the fundamental elements for cyber-physical systems, digital twin, industrial internet of things, etc. Configuring the components in SCIPs and modeling their interaction and operation mechanisms are important during SCIPs design. However, existing product design methods were originally developed for none smart and connected products. This could limit the accuracy of SCIP modeling during the design stage and consequently, it may cause more reworks during the implementation stage of the designed SCIPs. In this regard, a SCIP configuration and operation design method is established, including (i) meta knowledge graph (KG)-based configuration of the components in the physical system and status monitoring system of a required SCIP, (ii) event-state swimlane flowchart-based analysis of the dynamic interaction, operation, and data monitoring mechanisms among the components, and (iii) event-state KG based modeling of the overall workflow, monitoring data self-updating and intelligent operation mechanisms of the SCIP. Compared with existing SCIP design methods, the work provides a specific method for not only the configuration of the static components in customized SCIPs, but also the dynamic interaction, data acquisition/storing/transmitting, and intelligent function implementation mechanisms of the configured SCIP using a kind of event-state KG. The event-state KG is both human-readable and computer-programmable, and it can self-update according to predefined reasoning algorithms during the operation of the SCIP. The configuration and operation design modeling of a robot-based grinding processing line is used as a case study.

A new sensor configuration design method for source term estimation in urban neighborhood with complex conditions under different wind directions

When hazardous substances leak into the atmosphere, Source Term Estimation (STE) can quickly determine the information of the leaked substance to control the threat of the leakage event to the environment and public safety. Reasonable sensor configuration is the foundation of STE. Existing sensor configuration schemes have limited applicability in STE processes. When urban neighborhood has complex building structures and airflow conditions, there is a lack of a method that can provide reasonable sensor configurations to ensure good STE performance. In this study, a new sensor configuration design method is proposed, which weights the joint entropy of adjoint concentration information of multi wind directions to obtain the cost function, and then uses Simulated Annealing (SA) algorithm to minimize the cost function. This article selects a real complex urban neighborhood for simplified modeling, and designs the optimal sensor array for it. STE results of several leakage scenarios are compared with the optimal and uniform sensor configurations at different leakage locations and wind directions. Compared to traditional uniform sensor configurations, the optimal sensor configuration has significantly improved estimation performance in both source location and strength, with a reduction of 27 %–51 % in the bias of source location identification and 17 %–39 % in the bias of source strength estimation.

Optimum design method for structural configuration and fiber arrangement for fiber-reinforced composites

Fiber-reinforced composite materials, exemplified by CFRP, offer the possibility of achieving lightweight, high-stiffness, and high-strength structures by continuously and evenly distributing fibers. While topology and orientation optimization methods have been developed for anisotropic materials in the past, there remains a gap in design methods that consider manufacturability, especially for continuous fiber materials. In this study, we propose a design method that takes into account manufacturability, focusing on the aspects of continuity and uniformity in fiber-reinforced composite optimum design. Specifically, we introduce a two-stage optimization approach. In the first stage, we conduct concurrent optimization of topology and fiber orientation. We utilize a level-set function to represent topological configuration, while for orientation, we introduce a “double angle vector”, which enables us to consider fiber properties such as angular periodicity. These design variables are updated by solving partial differential equations based on reaction–diffusion equations. In the second stage, leveraging the optimal orientations obtained in the first stage, we optimize the path-line generation for the manufacture of continuous fiber materials. We introduce a scalar function representing path lines and formulate an optimization problem to ensure that the path lines are both evenly spaced and continuous. The update of design variables in this state is also achieved via solving the partial differential equation. Through the development of this two-stage optimization method, we aim to create an optimal structure with manufacturable continuous fiber materials, incorporating both the topology and fiber orientation that satisfy the requirements of continuity and uniformity.

Optimal Configuration of Heterogeneous Swarm for Cooperative Detection with Minimum DOP Based on Nested Cones

When unmanned platforms perform precise target detection, the configuration of detection nodes will significantly impact accuracy. Aiming to obtain the minimum dilution of precision (DOP), this paper innovatively proposes an optimal detection configuration design method focused on the heterogeneous unmanned cooperative swarm based on the nested cone model. The proposed method first divides the swarm into different groups according to the performances of platforms and then uses a conical nested configuration to arrange the placement of each node independently. The paper considers the problem of the inaccurate prior position of the target and replaces the single-point DOP with the average DOP on the prior region of the target as the optimization objective. Considering the unavoidable positioning errors in engineering practice, this paper provides the optimal configuration of the detection group (DG) and anchor group (AG) in the swarm to reduce the impact caused by positioning errors of detection nodes. We set a certain swarm consisting of 3 types of platforms to design the configuration by simulation experiments and find the optimal parameters for nested cones to realize accurate detection.

Configuration Design and Performance Analysis of a Three‐Power Source Power Transmission System Based on Lever Method

This paper proposes a supplementary design method for a three‐power source hybrid power transmission system based on the lever method, aimed at enhancing its power performance and economic efficiency. It makes up for some defects of traditional configuration design methods. Firstly, in order to better show the connection between the two planetary rows in the composite distribution configuration, an equivalent lever model with four nodes was established. The rod model was screened based on the connection relationship between the mechanical point distribution and power source. The rod model was analyzed in combination with the motor speed and torque characteristics, and the value interval of the two mechanical points of the composite distribution rod model was obtained. Then, the four‐node rod model was split. By adding the clutch and brake to control the connection between different nodes of the planetary bank, the working mode of the configuration can be switched. The supplementary design was carried out by increasing the input distribution to compensate for the low efficiency of the composite distribution configuration when driving at low speed, and three optimal configurations were obtained. (Based on the constraints of factors such as rod length, there are finally three solutions that meet the requirements.) Finally, the vehicle dynamics model was established, and the simulation results based on the dynamic programming principle showed that compared with the typical three‐power configuration Prius+, the fuel economy of the optimal configuration was improved in different degrees. Configuration (II) was selected as the object for parameter optimization, and the results showed that the power performance of the vehicle is improved by 1.8%, and the economy is improved by 5.47%, which verifies the validity of the configuration design method proposed in this paper.

Configuration Design Method of Mega Constellation for Low Earth Orbit Observation

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.

Experimental characterization of a spiral heat exchanger for waste water heat recovery from partially filled sewage pipes

This paper focuses on the experimental characterization of horizontal, spiral heat exchangers used for heat recovery from sewage pipes. Such non-intrusive heat exchanger configurations are appealing for this application, but they often exhibit reduced heat exchange performances compared to more compact designs. To compare the performance of this configuration with that of an ideal counter-flow heat exchanger, a representative test setup was constructed. As the sewer pipes are generally not completely filled, tests were conducted using three different fillings (100%, 50%, 33%) and a filling parameter z was introduced in the heat transfer equations. Correction factors to be applied in the Logarithmic Mean Temperature Difference (LMTD) design method for this specific spiral configuration were derived from the test results. It was found that the filling of the sewer pipe has minimal impact on the correction factor, which ranges between 0.78 and 0.83. The average value of 0.81 is recommended for design purposes.

Optimal design method for electrochromic window split-pane configuration to enhance building energy efficiency

Electrochromic (EC) windows can prevent glare by adjusting their tinting state, but the tinted EC glass will affect the use of daylight in the room, resulting in the increase of lighting energy consumption. Splitting the EC window into several panes and tinting only a portion of them can effectively mitigate the conflict between glare prevention and the usage of daylight. However, there is a lack of design methods for EC window split pane configurations to realize further lighting energy-saving potential. To address this problem, this study proposed an optimal design method for EC window split pane configuration. This method is based on the glare calculation model and aims to obtain the minimum tinted area hours (TAH) of the EC window. Taking a south-facing EC window office building in Beijing as a case study, the effectiveness of the proposed design method was investigated by simulation. Results show the proposed design method identified the most energy-efficient and comfortable split panes scheme. By combining with the split-pane glare control method, 95.3% of intolerable glare was prevented, and a useful daylight illumination index of 73.3% was achieved. It also significantly improved building energy efficiency, saving 29.8% of lighting energy consumption compared to whole window design scheme. This study provides a promising design methodology for the high-performance application of EC windows in buildings.

Optimization Effect of the Improved Power System Integrating Composite Motors on the Energy Consumption of Electric Vehicles

The multi-power source coupled transmission system is a high-performance and energy-saving potential power transmission system, and most of the commonly used pure electric vehicles in the market that use multi-power source coupled drive adopt the motor dual-axis distributed independent drive scheme. The configuration design method for multi-power source fusion hybrid systems mainly focuses on the search and selection of power split hybrid systems based on planetary gear mechanisms. But it has not yet covered the configuration design of transmission systems, resulting in a lack of universal expression and generation methods for the configuration of multi-power source fusion hybrid systems in pure electric vehicles. Therefore, to solve the configuration optimization design problem of a dual-motor single-planetary-array power system, an improved general matrix topology design method is proposed to generate all feasible topology structures. And energy consumption, economy, and the dynamic performance of alternative configurations are optimized and simulated through the control strategy based on a dynamic programming algorithm. Under comprehensive testing conditions, 25 alternative options that met the screening criteria were selected, and, ultimately, five optimized configuration options were obtained. Configuration 1 has the best economy, reducing energy consumption by about 6.3%and increasing driving range by about 6.7%. Its 0–100 km/h acceleration time is about 31.4% faster than the reference configuration. In addition, the energy consumption economy during actual driving is almost the same as the theoretical optimal energy consumption economy, with a difference of only 0.3%. The success of this study not only provides an innovative method for optimizing the configuration of dual-motor single-row star train power systems, but also has a positive impact on improving energy utilization efficiency, reducing energy consumption, and improving the overall performance of electric vehicles.

Configuration design and collision dynamics analysis of flexible nets for space debris removal

Tether-nets are one of the most promising approaches for active removal of space debris. This paper investigated the collision dynamics of flexible nets with different configurations, the focus is on the selection of an optimal configuration with respect to collision dynamics. Firstly, the design method of net configuration is proposed based on undirected graph theory, and five flexible nets with different configurations are designed, including quadrilateral, pentagon, octagon, dodecagon and circle. Secondly, the collision dynamics model is presented and its effectiveness is verified via numerical simulations and ground experiments. Finally, collision dynamics of the five flexible nets are simulated based on the verified model and the differences of these nets are compared and analyzed. Comparison results show that the flexible net with octagon configuration has better collision dynamics than others according to the maximum deformation, stress, and energy dissipation during the collision process, which provided an optimal configuration of flexible nets for space debris removal.

A multi-objective joint optimisation method for simultaneous part family formation and configuration design in delayed reconfigurable manufacturing system (D-RMS)

ABSTRACT 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.