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1 – 10 of over 22000Renluan Hou, Jianwei Niu, Yuliang Guo, Tao Ren, Bing Han, Xiaolong Yu, Qun Ma, Jin Wang and Renjie Qi
The purpose of this paper is to enhance control accuracy, energy efficiency and productivity of customized industrial robots by the proposed multi-objective trajectory optimization…
Abstract
Purpose
The purpose of this paper is to enhance control accuracy, energy efficiency and productivity of customized industrial robots by the proposed multi-objective trajectory optimization approach. To obtain accurate dynamic matching torques of the robot joints with optimal motion, an improved dynamic model built by a novel parameter identification method has been proposed.
Design/methodology/approach
This paper proposes a novel multi-objective optimal approach to minimize the time and energy consumption of robot trajectory. First, the authors develop a reliable dynamic parameters identification method to obtain joint torques for formulating the normalized energy optimization function and dynamic constraints. Then, optimal trajectory variables are solved by converting the objective function into relaxation constraints based on second-order cone programming and Runge–Kutta discrete method to reduce the solving complexity.
Findings
Extensive experiments via simulation and in real customized robots are conducted. The results of this paper illustrate that the accuracy of joint torque predicted by the proposed model increases by 28.79% to 79.05% over the simplified models used in existing optimization studies. Meanwhile, under the same solving efficiency, the proposed optimization trajectory consumes a shorter time and less energy compared with the existing optimization ones and the polynomial trajectory.
Originality/value
A novel time-energy consumption optimal trajectory planning method based on dynamic identification is proposed. Most existing optimization methods neglect the effect of dynamic model reliability on energy efficiency optimization. A novel parameter identification approach and a complete dynamic torque model are proposed. Experimental results of dynamic matching torques verify that the control accuracy of optimal robot motion can be significantly improved by the proposed model.
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Irina Farquhar and Alan Sorkin
This study proposes targeted modernization of the Department of Defense (DoD's) Joint Forces Ammunition Logistics information system by implementing the optimized innovative…
Abstract
This study proposes targeted modernization of the Department of Defense (DoD's) Joint Forces Ammunition Logistics information system by implementing the optimized innovative information technology open architecture design and integrating Radio Frequency Identification Device data technologies and real-time optimization and control mechanisms as the critical technology components of the solution. The innovative information technology, which pursues the focused logistics, will be deployed in 36 months at the estimated cost of $568 million in constant dollars. We estimate that the Systems, Applications, Products (SAP)-based enterprise integration solution that the Army currently pursues will cost another $1.5 billion through the year 2014; however, it is unlikely to deliver the intended technical capabilities.
LianZheng Ge, Jian Chen, Ruifeng Li and Peidong Liang
The global performance of industrial robots partly depends on the properties of drive system consisting of motor inertia, gearbox inertia, etc. This paper aims to deal with the…
Abstract
Purpose
The global performance of industrial robots partly depends on the properties of drive system consisting of motor inertia, gearbox inertia, etc. This paper aims to deal with the problem of optimization of global dynamic performance for robotic drive system selected from available components.
Design/methodology/approach
Considering the performance specifications of drive system, an optimization model whose objective function is composed of working efficiency and natural frequency of robots is proposed. Meanwhile, constraints including the rated and peak torque of motor, lifetime of gearbox and light-weight were taken into account. Furthermore, the mapping relationship between discrete optimal design variables and component properties of drive system were presented. The optimization problem with mixed integer variables was solved by a mixed integer-laplace crossover power mutation algorithm.
Findings
The optimization results show that our optimization model and methods are applicable, and the performances are also greatly promoted without sacrificing any constraints of drive system. Besides, the model fits the overall performance well with respect to light-weight ratio, safety, cost reduction and others.
Practical implications
The proposed drive system optimization method has been used for a 4-DOF palletizing robot, which has been largely manufactured in a factory.
Originality/value
This paper focuses on how the simulation-based optimization can be used for the purpose of generating trade-offs between cost, performance and lifetime when designing robotic drive system. An applicable optimization model and method are proposed to handle the dynamic performance optimization problem of a drive system for industrial robot.
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Imen Amdouni, Lilia El Amraoui, Frédéric Gillon, Mohamed Benrejeb and Pascal Brochet
– The purpose of this paper is to develop an optimal approach for optimizing the dynamic behavior of incremental linear actuators.
Abstract
Purpose
The purpose of this paper is to develop an optimal approach for optimizing the dynamic behavior of incremental linear actuators.
Design/methodology/approach
First, a parameterized design model is built. Second, a dynamic model is implemented. This model takes into account the thrust force computed from a finite element model. Finally, the multiobjective optimization approach is applied to the dynamic model to optimize control as well as design parameters.
Findings
The Pareto front resulting from the optimization approach (or the parallel optimization approach,) is better than the Pareto, which is obtained from the only application of MultiObjective Genetic Algorithm (MOGA) method (or parallel MOGA with the same number of optimization approach objective function evaluations). The only use of MOGA can reach the region near an optimal Pareto front, but it consumes more computing time than the multiobjective optimization approach. At each flowchart stage, parallelization leads to a significant reduction of computing time which is halved when using two-core machine.
Originality/value
In order to solve the multiobjective problem, a hybrid algorithm based on MOGA is developed.
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This paper gives a bibliographical review of the finite element and boundary element parallel processing techniques from the theoretical and application points of view. Topics…
Abstract
This paper gives a bibliographical review of the finite element and boundary element parallel processing techniques from the theoretical and application points of view. Topics include: theory – domain decomposition/partitioning, load balancing, parallel solvers/algorithms, parallel mesh generation, adaptive methods, and visualization/graphics; applications – structural mechanics problems, dynamic problems, material/geometrical non‐linear problems, contact problems, fracture mechanics, field problems, coupled problems, sensitivity and optimization, and other problems; hardware and software environments – hardware environments, programming techniques, and software development and presentations. The bibliography at the end of this paper contains 850 references to papers, conference proceedings and theses/dissertations dealing with presented subjects that were published between 1996 and 2002.
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Amer Fahmy, Tarek Hassan, Hesham Bassioni and Ronald McCaffer
Basic project control through traditional methods is not sufficient to manage the majority of real-time events in most construction projects. The purpose of this paper is to…
Abstract
Purpose
Basic project control through traditional methods is not sufficient to manage the majority of real-time events in most construction projects. The purpose of this paper is to propose a Dynamic Scheduling (DS) model that utilizes multi-objective optimization of cost, time, resources and cash flow, throughout project construction.
Design/methodology/approach
Upon reviewing the topic of DS, a worldwide internet survey with 364 respondents was conducted to define end-user requirements. The model was formulated and solution algorithms discussed. Verification was reported using predefined problem sets and a real-life case. Validation was performed via feedback from industry experts.
Findings
The need for multi-objective dynamic software optimization of construction schedules and the ability to choose among a set of optimal alternatives were highlighted. Model verification through well-known test cases and a real-life project case study showed that the model successfully achieved the required dynamic functionality whether under the small solved example or under the complex case study. The model was validated for practicality, optimization of various DS schedule quality gates, ease of use and software integration with contemporary project management practices.
Practical implications
Optimized real-time scheduling can provide better resources management including labor utilization and cost efficiency. Furthermore, DS contributes to optimum materials procurement, thus minimizing waste.
Social implications
Optimized real-time scheduling can provide better resources management including labor utilization and cost efficiency. Furthermore, DS contributes to optimum materials procurement, thus minimizing waste.
Originality/value
The paper illustrates the importance of DS in construction, identifies the user needs and overviews the development, verification and validation of a model that supports the generation of high-quality schedules beneficial to large-scale projects.
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Yanbo Feng, Xiande Wu, Weidong Chen, Yaen Xie, Taihang Yu and Yong Hao
On-orbit assembly technology is a promising research topic in spaceflight field. For purposes of studying the dynamic performance and reducing weight of an on-orbit assembly…
Abstract
Purpose
On-orbit assembly technology is a promising research topic in spaceflight field. For purposes of studying the dynamic performance and reducing weight of an on-orbit assembly satellite structure frame, this paper aims to propose a structural optimization design method based on natural frequency.
Design/methodology/approach
The dynamic stability of the satellite under working condition depends on the mechanical properties of the structure matrix. A global structural optimization model is established, with the objective of mass minimization and the constraints of given natural frequencies and given structure requirements. The structural optimization and improvement design method is proposed using sequential quadratic programming calculation.
Findings
The optimal result of objective function is effectively obtained, and the best combination of structural geometric parameters is configurated. By analyzing the relationship between the structural variables and optimization parameters, the primary and secondary factors to the mass optimization process of the microsatellite satisfying the dynamic performance requirements are obtained, which improves the effectiveness and accuracy of the system optimization design.
Originality/value
This method can coordinate the relation between satellite vibration stability and weight reduction, which provides an effective way for the optimization design of on-orbit assembly microsatellite. It has reference significance for the similar spacecraft framework structure design.
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Ann Tighe, Finlay S. Smith and Gerard Lyons
To show the successful use of self‐organising fuzzy control in enhancing dynamic optimisation, a controller is used to direct the type of optimisation appropriate in each new…
Abstract
Purpose
To show the successful use of self‐organising fuzzy control in enhancing dynamic optimisation, a controller is used to direct the type of optimisation appropriate in each new dynamic problem. The system uses its experiences to determine which approach is most suitable under varying circumstances.
Design/methodology/approach
A knowledge extraction tool is used to gain basic information about the solution space with a simple computation. This information is compared with the fuzzy rules stored in the system. These rules hold a collection of facts on previous successes and failures, which were acquired through the performance monitor. Using this system the controller directs the algorithms, deciphering the most appropriate strategy for the current problem.
Research limitations/implications
This procedure is designed for large scale dynamic optimisation problems, where a portion of the computational time is sacrificed to allow the controller to direct the best possible solution strategy. The results here are based on smaller scale systems, which illustrate the benefits of the technique.
Findings
The results highlight two significant aspects. From the comparison of the three algorithms without the use of the controller, a pattern can be seen in how the algorithms perform on different types of problems. Results show an improvement in the overall quality when the controller is employed.
Originality/value
This paper introduces a novel approach to the problem dynamic optimisation. It combines the control ability of self‐organising fuzzy logic with a range of optimisation techniques to obtain the best possible approach in any one situation.
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Si Chen, Haoran Lv, Yinming Zhao and Minning Wang
This paper aims to provide a new method to study and improve the dynamic characteristics of the four-column resistance strain force sensor through the elastomer structure design…
Abstract
Purpose
This paper aims to provide a new method to study and improve the dynamic characteristics of the four-column resistance strain force sensor through the elastomer structure design and optimization.
Design/methodology/approach
Based on the mechanism analysis method, the authors first present a dynamic characteristic model of the four-column resistance strain force sensors’ elastomer. Then, the authors verified and modified the model according to the Solidworks finite element simulation results. Finally, the authors designed and optimized two types of four-column elastomers based on the dynamic characteristic model and verified the improvement of sensor dynamic performance through a hammer knock dynamic experiment.
Findings
The Solidworks finite element simulation and hammer knock dynamic experiment results show that the relative error of the model is less than 10%, which confirms the accuracy of the model. The dynamic performance of the sensors based on the model can be improved by more than 30%, which is a great improvement in sensor dynamic performance.
Originality/value
The authors first present a dynamic characteristic model of the four-column elastomer and optimize the four-column sensors successfully based on the mechanism analysis method. And a new method to study and improve the dynamic characteristics of the resistance is provided.
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Mehmet Eren Uz, Pezhman Sharafi, Mahya Askarian, Weiqing Fu and Chunmei Zhang
The preliminary layout design of structures impacts upon the entire design process and, consequently, the total cost. The purpose of this paper is to select the most economical…
Abstract
Purpose
The preliminary layout design of structures impacts upon the entire design process and, consequently, the total cost. The purpose of this paper is to select the most economical layouts that satisfy structural and architectural requirements, while considering the reciprocal effects of cost factors and layout variables at the preliminary stages of design.
Design/methodology/approach
This paper presents an automated method for cost optimization of geometric layout design of multi-span reinforced concrete (RC) beams subjected to dynamic loading by using the charged system search (CSS) algorithm. First, a novel cost optimization approach for geometric layout problems is introduced, in which both cost parameters and dynamic responses are considered in the preliminary layout design of beams. The proposed structural optimization problem with constraints on the static and dynamic equilibrium, architectural dimensions and structural action effects is solved using the CSS algorithm.
Findings
The proposed CSS algorithm for solving the cost optimization problem can be easily used for optimizing the span lengths and is also capable of working with various cost functions. The presented examples show that the proposed algorithm using the new cost optimization function provides satisfactory results and can result in over 7 per cent cost saving.
Originality/value
This is an original paper proposing a novel methodology for preliminary layout design of concrete beams.
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