scholarly journals Homotopy Directed Optimization to Design a Six-Bar Linkage for a Lower Limb With a Natural Ankle Trajectory

2016 ◽  
Vol 8 (6) ◽  
Author(s):  
Brandon Y. Tsuge ◽  
Mark M. Plecnik ◽  
J. Michael McCarthy
Keyword(s):  
Lower Limb ◽  
Polynomial System ◽  
Optimization Technique ◽  
Synthesis Method ◽  
Optimization Techniques ◽  
Path Generation ◽  
Optimization Strategy ◽  
Direct Solution ◽  
New Formulation ◽  
Path Synthesis

This paper presents a synthesis method for the Stephenson III six-bar linkage that combines the direct solution of the synthesis equations with an optimization strategy to achieve increased performance for path generation. The path synthesis equations for a six-bar linkage can reach as many as 15 points on a curve; however, the degree of the polynomial system is 1046. In order to increase the number of accuracy points and decrease the complexity of the synthesis equations, a new formulation is used that combines 11 point synthesis with optimization techniques to obtain a six-bar linkage that minimizes the distance to 60 accuracy points. This homotopy directed optimization technique is demonstrated by obtaining a Stephenson III six-bar linkage that achieves a specified gait trajectory.

Multi-Objective Thermoeconomic Optimization of Coupling MSF Desalination With PWR Nuclear Power Plant

2008 ◽  
Author(s):  
Mohammad Hasan Khoshgoftar Manesh ◽  
Majid Amidpour ◽  
Mohammad Hosein Hamedi
Keyword(s):  
Power Plant ◽  
Nuclear Power ◽  
Thermodynamic Simulation ◽  
Optimization Technique ◽  
Optimization Techniques ◽  
Feed Water ◽  
Optimization Strategy ◽  
Thermal Systems ◽  
Pressurized Water ◽  
Multi Objective

Thermodynamic simulation programs are widely used for designing complex thermal systems but most of them don’t incorporate second law optimization techniques. In this study, an efficient optimization strategy is presented, which integrates a well-known Evolutionary Algorithms optimization technique with a professional power plant and cogeneration simulator, so as perform exergoeconomic optimization of complex thermal systems and generating combined pinch and exergy representations. This paper deals with the application of an evolutionary algorithm to multi-objective thermoeconomic optimization of coupling desalination plant with pressurized water reactor. The thermodynamic simulation of this plant has been performed in THERMOFLEX simulator. An Excel Add-in called THERMOFLEX Link has been developed to calculate the exergy of each stream from a THERMOFLEX simulation results. In addition, computer code has been developed for thermoeconomic and improved combined pinch-exergy analysis in MATLAB environment. Both design configuration and the process variables are optimized simultaneously. The optimization algorithm can choose among several design options included in a superstructure of the feed water heaters and MSF desalination in dual purpose plant. For the assumptions and simplifications made in this study, a 3000 MWth PWR power plant similar to Bushehr power plant has been considered.

Synthesis of a Spatial RRSS Mechanism for Path Generation Using the Numerical Atlas Method

2019 ◽  
Vol 142 (1) ◽  
Author(s):  
Wenrui Liu ◽  
Jianwei Sun ◽  
Jinkui Chu
Keyword(s):  
Rotation Angle ◽  
Synthesis Method ◽  
Path Generation ◽  
Feature Parameters ◽  
Atlas Method ◽  
Path Synthesis ◽  
The Mathematical Model ◽  
The Relationship ◽  
Generation Problem ◽  
Actual Size

Abstract An open path synthesis method for a spatial revolute-revolute-spherical-spherical (RRSS) mechanism is presented in this paper. The mathematical model for the trajectory curve is established. The characteristics of an RRSS mechanism in a standard installation position are revealed: the projection points of the coupler curve on the Oxy plane rotate by the corresponding input angles around the z-axis, and the generated points lie on an ellipse. Based on this finding, a 17-dimensional path generation problem can be translated into two lower-dimensional matching recognition problems and one actual size and installation position calculation problem. The path generation can be achieved by three steps. First, a database of four dimensional rotation angle parameters is established. By comparing the similarities between the mechanism feature curve of the prescribed open curve and its corresponding mechanism feature ellipse (MFE), the angles of installation, the initial angle of the input link, and the elliptic feature parameters of the desired RRSS mechanism can be approximately determined. Then, a 13-dimensional dynamic self-adapting numerical atlas database is established, which contains six basic dimensional types (BDTs) and seven wavelet feature parameters, and the BDTs of the desired RRSS mechanism are obtained. Finally, based on the relationship between the MFE of the prescribed curve and the BDTs of the desired RRSS mechanism, the calculation models for the actual link lengths and installation positions of the desired RRSS mechanism were established. Three examples are presented in this paper.

On the Solution of Multi-Precision-Point Path Synthesis of Planar Four-Bar Mechanisms Based on Solution Region Methodology

2018 ◽  
Author(s):  
Jianyou Han ◽  
Wupeng Liu
Keyword(s):  
Infinite Number ◽  
Feasible Solution ◽  
Synthesis Method ◽  
Path Generation ◽  
Number Of Solutions ◽  
Region Method ◽  
Different Types ◽  
Design Requirements ◽  
Solution Region ◽  
Path Synthesis

In this paper, the solution region synthesis method for multi-precision-point path synthesis of planar four-bar mechanisms is presented. The solution region method is to represent an infinite number of mechanism solutions in a plane, in which the x-coordinate and the y-coordinate of the plane are both taken as the concerned parameters of the mechanisms. Then the feature curves of the mechanisms can be expressed in the plane. Firstly, the synthesis equations for the multi-precision-point path synthesis of planar four-bar mechanisms are established. Then according to the proposed defect judgment method, the defective solutions are eliminated, and an infinite number of solutions without defects are obtained. After considering and imposing design requirements, the linkages of different types and different curve types are represented in the solution region. Finally, Taking the path generation of eight points as the example, the methodology of establishing the solution region and the feasible solution region are presented, and the synthesis results are illustrated.

scholarly journals Solving the Real Power Limitations in the Dynamic Economic Dispatch of Large-Scale Thermal Power Units under the Effects of Valve-Point Loading and Ramp-Rate Limitations

2021 ◽  
Vol 13 (3) ◽  
pp. 1274
Author(s):  
Loau Al-Bahrani ◽  
Mehdi Seyedmahmoudian ◽  
Ben Horan ◽  
Alex Stojcevski
Keyword(s):  
Large Scale ◽  
Thermal Power ◽  
Optimization Technique ◽  
Economic Dispatch ◽  
Pso Algorithm ◽  
Search Space ◽  
Economic Benefits ◽  
Optimization Techniques ◽  
Ramp Rate ◽  
Dynamic Economic Dispatch

Few non-traditional optimization techniques are applied to the dynamic economic dispatch (DED) of large-scale thermal power units (TPUs), e.g., 1000 TPUs, that consider the effects of valve-point loading with ramp-rate limitations. This is a complicated multiple mode problem. In this investigation, a novel optimization technique, namely, a multi-gradient particle swarm optimization (MG-PSO) algorithm with two stages for exploring and exploiting the search space area, is employed as an optimization tool. The M particles (explorers) in the first stage are used to explore new neighborhoods, whereas the M particles (exploiters) in the second stage are used to exploit the best neighborhood. The M particles’ negative gradient variation in both stages causes the equilibrium between the global and local search space capabilities. This algorithm’s authentication is demonstrated on five medium-scale to very large-scale power systems. The MG-PSO algorithm effectively reduces the difficulty of handling the large-scale DED problem, and simulation results confirm this algorithm’s suitability for such a complicated multi-objective problem at varying fitness performance measures and consistency. This algorithm is also applied to estimate the required generation in 24 h to meet load demand changes. This investigation provides useful technical references for economic dispatch operators to update their power system programs in order to achieve economic benefits.

scholarly journals Optimal Allocation of Multiple Types of Distributed Generations in Radial Distribution Systems Using a Hybrid Technique

2021 ◽  
Vol 13 (12) ◽  
pp. 6644
Author(s):  
Ali Selim ◽  
Salah Kamel ◽  
Amal A. Mohamed ◽  
Ehab E. Elattar
Keyword(s):  
Power System ◽  
Radial Distribution ◽  
Distribution Systems ◽  
Optimal Allocation ◽  
Optimization Technique ◽  
Mathematical Formulation ◽  
Optimization Techniques ◽  
Sensitivity Factor ◽  
Hybrid Technique ◽  
Analytical Technique

In recent years, the integration of distributed generators (DGs) in radial distribution systems (RDS) has received considerable attention in power system research. The major purpose of DG integration is to decrease the power losses and improve the voltage profiles that directly lead to improving the overall efficiency of the power system. Therefore, this paper proposes a hybrid optimization technique based on analytical and metaheuristic algorithms for optimal DG allocation in RDS. In the proposed technique, the loss sensitivity factor (LSF) is utilized to reduce the search space of the DG locations, while the analytical technique is used to calculate initial DG sizes based on a mathematical formulation. Then, a metaheuristic sine cosine algorithm (SCA) is applied to identify the optimal DG allocation based on the LSF and analytical techniques instead of using random initialization. To prove the superiority and high performance of the proposed hybrid technique, two standard RDSs, IEEE 33-bus and 69-bus, are considered. Additionally, a comparison between the proposed techniques, standard SCA, and other existing optimization techniques is carried out. The main findings confirmed the enhancement in the convergence of the proposed technique compared with the standard SCA and the ability to allocate multiple DGs in RDS.

scholarly journals Optimization of the Parameters of RISE Feedback Controller Using Genetic Algorithm

2016 ◽  
Vol 2016 ◽  
pp. 1-9
Author(s):  
Fayiz Abu Khadra ◽  
Jaber Abu Qudeiri ◽  
Mohammed Alkahtani
Keyword(s):  
Genetic Algorithm ◽  
Numerical Simulations ◽  
Control Algorithm ◽  
Chaotic Systems ◽  
Optimization Technique ◽  
Optimization Techniques ◽  
Algorithm Optimization ◽  
External Disturbances ◽  
Van Der Pol ◽  
Control Methodology

A control methodology based on a nonlinear control algorithm and optimization technique is presented in this paper. A controller called “the robust integral of the sign of the error” (in short, RISE) is applied to control chaotic systems. The optimum RISE controller parameters are obtained via genetic algorithm optimization techniques. RISE control methodology is implemented on two chaotic systems, namely, the Duffing-Holms and Van der Pol systems. Numerical simulations showed the good performance of the optimized RISE controller in tracking task and its ability to ensure robustness with respect to bounded external disturbances.

scholarly journals Ethiopian Banknote Recognition Using Convolutional Neural Network and Its Prototype Development Using Embedded Platform

2022 ◽  
Vol 2022 ◽  
pp. 1-18
Author(s):  
Dereje Tekilu Aseffa ◽  
Harish Kalla ◽  
Satyasis Mishra
Keyword(s):  
Optimization Technique ◽  
Research Work ◽  
Optimization Techniques ◽  
Magnetic Sensors ◽  
Batch Size ◽  
Raspberry Pi ◽  
Prototype Development ◽  
Embedded Platform ◽  
Artificial Intelligence Technology ◽  
Banknote Recognition

Money transactions can be performed by automated self-service machines like ATMs for money deposits and withdrawals, banknote counters and coin counters, automatic vending machines, and automatic smart card charging machines. There are four important functions such as banknote recognition, counterfeit banknote detection, serial number recognition, and fitness classification which are furnished with these devices. Therefore, we need a robust system that can recognize banknotes and classify them into denominations that can be used in these automated machines. However, the most widely available banknote detectors are hardware systems that use optical and magnetic sensors to detect and validate banknotes. These banknote detectors are usually designed for specific country banknotes. Reprogramming such a system to detect banknotes is very difficult. In addition, researchers have developed banknote recognition systems using deep learning artificial intelligence technology like CNN and R-CNN. However, in these systems, dataset used for training is relatively small, and the accuracy of banknote recognition is found smaller. The existing systems also do not include implementation and its development using embedded systems. In this research work, we collected various Ethiopian currencies with different ages and conditions and applied various optimization techniques for CNN architects to identify the fake notes. Experimental analysis has been demonstrated with different models of CNN such as InceptionV3, MobileNetV2, XceptionNet, and ResNet50. MobileNetV2 with RMSProp optimization technique with batch size 32 is found to be a robust and reliable Ethiopian banknote detector and achieved superior accuracy of 96.4% in comparison to other CNN models. Selected model MobileNetV2 with RMSProp optimization has been implemented through an embedded platform by utilizing Raspberry Pi 3 B+ and other peripherals. Further, real-time identification of fake notes in a Web-based user interface (UI) has also been proposed in the research.

scholarly journals Adaptive Day-Ahead Prediction of Resilient Power Distribution Network Partitions

2021 ◽  
Author(s):  
Chinmay Shah ◽  
Richard Wies
Keyword(s):  
Power Distribution ◽  
Renewable Energy Sources ◽  
Optimization Technique ◽  
Distribution Network ◽  
Distribution Networks ◽  
Optimization Techniques ◽  
Power Distribution Networks ◽  
Power Distribution Network ◽  
High Penetration ◽  
Islanded Mode

The conventional power distribution network is being transformed drastically due to high penetration of renewable energy sources (RES) and energy storage. The optimal scheduling and dispatch is important to better harness the energy from intermittent RES. Traditional centralized optimization techniques limit the size of the problem and hence distributed techniques are adopted. The distributed optimization technique partitions the power distribution network into sub-networks which solves the local sub problem and exchanges information with the neighboring sub-networks for the global update. This paper presents an adaptive spectral graph partitioning algorithm based on vertex migration while maintaining computational load balanced for synchronization, active power balance and sub-network resiliency. The parameters that define the resiliency metrics of power distribution networks are discussed and leveraged for better operation of sub-networks in grid connected mode as well as islanded mode. The adaptive partition of the IEEE 123-bus network into resilient sub-networks is demonstrated in this paper.

Structural sizing for the weight estimation of a very light aircraft wing

2018 ◽  
Vol 232 (14) ◽  
pp. 2681-2687
Author(s):  
Abdelkader Benaouali ◽  
Robert Rogólski ◽  
Stanisław Kachel
Keyword(s):  
Finite Element ◽  
Design Process ◽  
Geometric Modeling ◽  
Optimization Techniques ◽  
Product Development Process ◽  
Optimization Strategy ◽  
Aircraft Wing ◽  
Lattice Method ◽  
Vortex Lattice Method

The design process is no longer a trial-and-error procedure due to the introduction of computer-aided tools and optimization techniques. The product development process is therefore accelerated, allowing to produce more in a relatively lesser time. Moreover, the best possible design, with regard to the performance, can hence be obtained. When applied to the design of an aircraft wing, the optimization objective is usually to minimize the structural weight under failure-based constraints. This paper presents an optimization strategy that allows the determination of the wing surface structural thicknesses corresponding to the minimal weight while keeping the structure safe in terms of strength and buckling. This strategy is applied for the wing sizing process of a new two-seater very light aircraft, currently under development. The design process goes through geometric modeling, aerodynamic calculations using vortex lattice method, and finite element modeling. Structural optimization is performed within MATLAB, and is based on the automatic execution of the finite element solver MSC.NASTRAN.

Adapting Ant Colony for Topology Optimization of Compliant Mechanisms With Variable Material Density

2017 ◽  
Author(s):  
Nadim Diab
Keyword(s):  
Topology Optimization ◽  
Ant Colony Optimization ◽  
High Performance ◽  
Compliant Mechanisms ◽  
Optimization Technique ◽  
Optimization Techniques ◽  
Ant Colony ◽  
Intensity Level ◽  
Material Density ◽  
Swarm Intelligence Optimization

Swarm intelligence optimization techniques are widely used in topology optimization of compliant mechanisms. The Ant Colony Optimization has been implemented in various forms to account for material density distribution inside a design domain. In this paper, the Ant Colony Optimization technique is applied in a unique manner to make it feasible to optimize for the beam elements’ cross-section and material density simultaneously. The optimum material distribution algorithm is governed by two various techniques. The first technique treats the material density as an independent design variable while the second technique correlates the material density with the pheromone intensity level. Both algorithms are tested for a micro displacement amplifier and the resulting optimized topologies are benchmarked against reported literature. The proposed techniques culminated in high performance and effective designs that surpass those presented in previous work.

Sign in / Sign up

Export Citation Format

Share Document