Comparison of Methodologies for Optimal Design of a Composite Plate under Practical Design Constraints

2014 ◽  
Author(s):  
Robert M. Taylor ◽  
Mateen Admani ◽  
John M. Strain
Keyword(s):  
Optimal Design ◽  
Composite Plate ◽  
Design Constraints ◽  
Practical Design

Momentum exchange impact damper design methodology for object-wall-collision problems

2017 ◽  
Vol 24 (14) ◽  
pp. 3206-3218
Author(s):  
Yohei Kushida ◽  
Hiroaki Umehara ◽  
Susumu Hara ◽  
Keisuke Yamada
Keyword(s):  
Optimal Design ◽  
Design Methodology ◽  
Design Parameters ◽  
Momentum Exchange ◽  
Impact Damper ◽  
One Dimensional ◽  
Practical Design ◽  
Wall Collision ◽  
Damper Design ◽  
And Control

Momentum exchange impact dampers (MEIDs) were proposed to control the shock responses of mechanical structures. They were applied to reduce floor shock vibrations and control lunar/planetary exploration spacecraft landings. MEIDs are required to control an object’s velocity and displacement, especially for applications involving spacecraft landing. Previous studies verified numerous MEID performances through various types of simulations and experiments. However, previous studies discussing the optimal design methodology for MEIDs are limited. This study explicitly derived the optimal design parameters of MEIDs, which control the controlled object’s displacement and velocity to zero in one-dimensional motion. In addition, the study derived sub-optimal design parameters to control the controlled object’s velocity within a reasonable approximation to derive a practical design methodology for MEIDs. The derived sub-optimal design methodology could also be applied to MEIDs in two-dimensional motion. Furthermore, simulations conducted in the study verified the performances of MEIDs with optimal/sub-optimal design parameters.

Remarks on Conditions for the Validity of Parametric Decomposition in Optimal Design

1990 ◽  
Author(s):  
J. R. Jagannatha Rao ◽  
Panos Y. Papalambros
Keyword(s):  
Optimal Design ◽  
Present Article ◽  
Original Problem ◽  
Necessary Conditions ◽  
Special Problem ◽  
Problem Structure ◽  
Globally Convergent ◽  
Parametric Decomposition ◽  
Practical Design ◽  
Decomposition Strategies

Abstract Decomposition strategies are used in a variety of practical design optimization applications. Such decompositions are valid, if the solution of the decomposed problem is in fact also the solution to the original one. Conditions for such validity are not always obvious. In the present article, we develop conditions for two-level parametric decomposition under which: (1) isolated minima at the two levels imply an isolated minimum for the original problem; (2) necessary conditions at the two-levels are equivalent to the necessary conditions for the original problem; and, (3) a descent algorithm for computing Karush-Kuhn-Tucker points in decomposition formulations is globally convergent. Since no special problem structure is assumed, the results are general and could be used to evaluate the suitability of a variety of approaches and algorithms for decomposition strategies.

Optimal Design of Squeeze Film Supports for Flexible Rotors

1983 ◽  
Vol 105 (3) ◽  
pp. 487-494 ◽  
Author(s):  
M. D. Rabinowitz ◽  
E. J. Hahn
Keyword(s):  
Optimal Design ◽  
Vibration Amplitude ◽  
Operating Conditions ◽  
Squeeze Film ◽  
Rotor Vibration ◽  
Design Constraints ◽  
Supply Pressure ◽  
Flexible Rotors ◽  
Wide Range ◽  
Film Lubrication

Assuming central preloading, operation below the second bending critical speed, and full film lubrication, this paper presents a theoretical model which allows one, with minimum computation, to design squeeze film damped rotors under conditions of high unbalance loading. Closed form expressions are derived for the maximum vibration amplitudes pertaining to optimally damped conditions. The resulting vibration amplitude and transmissibility data of design interest are presented for a wide range of practical operating conditions on a single chart. It can be seen that for a given rotor, the lighter the bearing the more easily one can satisfy design constraints relating to allowable rotor vibration levels and lubricant supply pressure requirements. The data presented are shown to be applicable to a wide variety of rotors, and a recommended procedure for optimal design is outlined.

Innovative Design Based on Prototypes of the Main Mechanism of Table Lamp

2012 ◽  
Vol 198-199 ◽  
pp. 189-192
Author(s):  
Wan Chun Zhou ◽  
Jian Jun Lu
Keyword(s):  
Topological Structure ◽  
Kinematic Chain ◽  
Main Mechanism ◽  
Schematic Diagram ◽  
Design Constraints ◽  
Innovative Design ◽  
Kinematic Chains ◽  
Structure Characteristics ◽  
Practical Design ◽  
Number Synthesis

On the basis of analyzing the topological structure of an original mechanism, it leads to the generalized kinematic chain meeting the same topological structure characteristics of the original mechanism in accordance with the generalized principle of mechanism, number synthesis of kinematic chain and compound hings. Allocation of ground links and performing links in the kinematic chain can get all feasible specialized kinematic chains while considering practical design constraints. In the final step, concrete schematic diagram of mechanism being restored from specialized kinematic chains leads to a series of new mechanism different from the original one. Designers ascertain appropriate new mechanism after selection and analysis.

Optimal design of elastic beams under multiple design constraints

1988 ◽  
Vol 24 (4) ◽  
pp. 331-349 ◽  
Author(s):  
G.I.N. Rozvany ◽  
K.M. Yep ◽  
T.G. Ong ◽  
B.L. Karihaloo
Keyword(s):  
Optimal Design ◽  
Design Constraints ◽  
Elastic Beams

Minimum Weight Design of a Car Trunk Deck-Lid Subject to Overall Stiffness Constraints

1982 ◽  
Vol 104 (4) ◽  
pp. 831-836 ◽  
Author(s):  
H. A. Du ◽  
S. C. Tang
Keyword(s):  
Minimum Weight ◽  
Optimization Technique ◽  
Design Procedure ◽  
Optimization Techniques ◽  
Structural Components ◽  
Minimum Weight Design ◽  
Design Constraints ◽  
Design Variables ◽  
Practical Design ◽  
Weight Design

A design procedure for a car trunk deck-lid using an approximate optimization technique is presented. Selecting the deck-lid gages and deck-lid inner panel configuration as design variables and overall stiffnesses as constraints, a possible weight reduction of 20 percent is demonstrated, compared with the base production deck-lid design. Although other practical design constraints might not allow one to achieve this goal, the potential value of optimization techniques is clearly demonstrated by this study. It is concluded that it could be useful to develop and apply such a procedure to components such as hoods, deck-lids, doors, and fenders, which are isolatable as structural components.

Optimal Design of Laminated Composite Plates for Maximum Buckling Load Using Genetic Algorithm

2005 ◽  
Vol 219 (9) ◽  
pp. 869-878 ◽  
Author(s):  
C. W. Kim ◽  
J. S. Lee
Keyword(s):  
Genetic Algorithm ◽  
Optimal Design ◽  
Uniaxial Compression ◽  
Composite Plate ◽  
Laminated Composite ◽  
Composite Plates ◽  
Buckling Load ◽  
Laminated Composite Plates ◽  
Worst Case ◽  
Case Design

An optimization procedure using a genetic algorithm (GA) is proposed to determine the optimal stacking sequence of laminated composite plates for the maximum buckling load under several different loadings, such as uniaxial compression, shear, biaxial compression, and the combination of shear and biaxial loadings. A series of optimal design is conducted for composite laminates having different aspect ratios, load conditions, and number of plies. Critical buckling load is taken as fitness function and fibre orientations are taken as design variables. A performance index is introduced to represent the effectiveness of optimal design with respect to worst case design. Then, for uniaxial compression loading, postbuckling behaviour is analysed numerically for the optimally designed composite plates as well as the worst case design composite plate. It shows the outstanding postbuckling performance of one of the optimally designed composite plates against the worst case design composite plate. Also, a GA finds the global solution without requiring auxiliary information such as derivatives of the objective function.

Sign in / Sign up

Export Citation Format

Share Document