Mechanical Engineering, Indian Institute of Science, Bengaluru, 560 012, India
"The more you think, the less material you need"
ME260
Structural Optimization: Size, Shape, and Topology
Aug. 2023 to Nov. 2023
Instructor: G. K. Ananthasuresh, Room 106, ME Building, suresh at iisc.ac.in
Teaching assistant: To be decided, M2D2 lab in mecheng, someone at iisc.ac.in
Lectures: Tu, Th: 08:30 AM - 10:00 AM; Venue: ME MMCR

Timeline and lecture notes

Week Dates Topics Notes Others
1 - 5 Module 1: Structural design with finite-variable optimization
1 Aug. 8, 2023: Overview of the course (Size, shape and topology optimization)
Template of a structural optimization problem: What we need to learn and how to formulate problems
Identifying size, shape, and topology optimization problems
Aug. 10,2023: Finite variable optimization vs. calculus of variation; and how they relate to structural optimization
Lecture notes 1
Lecture notes 2
Lecture notes 3
Article on strctural hierarchy by Prof. Lakes
Article on Eiffel's optimal structures
2 Aug. 15, 2023: No class due to Indian Independence Day.
Aug. 17, 2023: Unconstrained and constrained minimization
Lecture notes 4
Lecture notes 5
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3 Aug. 22, 2023: Constrained minimization; duality; two-bar truss optimization
Aug. 24, 2023: Multi-bar truss optimization
Lecture notes 6
Lecture notes 6 extra (duality)
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4 Aug. 29, 2023: Size (and topology) optimization of trusses and the optimality criteria algorithm
Aug. 31, 2023: Dual formulation of truss optimization for statically determinate trusses
Concepts of states of self stress and Maxwell's rule
Simultaneous geoemtry and material optimization of trusses
Lecture notes 7a
Lecture notes 7b
Lecture notes 8a
FEA theory notes (trusses and beams)
Matlab truss analysis code
Matlab truss optimization code
5 Sep. 5, 2023: Dual formulation of truss optimization for statically determinate trusses
Concepts of states of self stress and Maxwell's rule
Sep. 7, 2023: Dual method for truss optimizaition
Simultaneous geoemtry and material optimization of trusses
Lecture notes 8b
Lecture notes 9
Truss optimization using the dual method
Dual truss opt code
Geormetry+material optimization paper
6 - 11 Module 2: Structural optimization in the framework of calculus of variations
6 Sep. 12, 2023: Genesis of calculus of variations
Formulating variational problems in geometry and mechanics
Sep. 14, 2023: Mathematical preliminaries of calculus of variations: vectors spaces, function spaces, etc.
Genesis of calculus of variations
Geometry and mechanics problems cast as calculus of variations problems
Mathematical preliminaries to calculus of variations; functional and function spaces
Banach, Sobolev, etc., spaces
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7 Sep. 19, 2023: No class due to Vinayaka Chavithi
Sep. 21, 2023: Gateaux (first) variation, Frechet differential, etc.
Fundamental lemma of calculus of variations
Some examples to practise taking variation
Fundamental lemma of calculus of variations
First variation of a functional
Fundamental lemma of calculus of variations
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8 Sep. 26, 2023: Euler-Lagrage equations; multiple functions and multiple derivatives Practice with Gateaux variation and EL equations
Sep. 28, 2023: Euler-Lagrange equations when there are two and three independent variables
Euler-Lagrage equations with global (functional) and local (function) constraints
Euler-Lagrange equations in multiple functions and multiple derivatives but in a single domain variable Functionals with two independent variables
Euler-Lagrange equations with global (functional) constraints
Euler-Lagrange equations with local (function) constraints
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9 Oct. 3, 2023: Variable end conditions in Calculus of Variations; transversality conditions; broken extremals; Weirstrass-Erdmann conditions
Oct. 5, 2023: Optimization of a bar (a dozen problems)
Bar optimization code in Matlab
Variable end conditions of a functional
A dozen optimization problems of a bar
Solutions of two bar optimization problems
Bar optimization code
10 Oct. 10, 2023: Beam optmization problems
Oct. 12, 2023: 2D frame optimization problems; stiffness, strength, and flexibility
Beam optimization code in Matlab
Many beam optimization problems
Solution to beam optmization for stiffness and flexibility
2D frame optimization problem
Beam optimization for strength
Beam optimization code
11 Oct. 17, 2023: Homogenization method and its role in topology optimization; power law and material interpolation
Oct. 19, 2023: 1D homogenization using asymptotic expansion method
Playing with 99-line code to understand the influence of the penalty parameter and sensitivity filter
YinSyn code for stiff structures and compliant mechanisms
99-line code for 2D stiff-structure optimization
YinSyn 2D code for topology optimization of structures and compliant mechanisms
12 - 15 Module 3: Multiphysics design problems; Sensitivity analysis for shape and topology optimization
12 Oct. 24, 2023: No class due to Dasara
Oct. 26, 2023: Topology optimization of compliant mechanisms in 2D continuum
Multiphysics design problems
Papers sent by email as a zip file.
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13 Oct. 31, 2023: Pressure load problem and electro-thermal-elastic problem
Ananlytical expressions for sensitivity from the Calculus of Variations framework
Nov. 2, 2023: Topology optimization for electro-elasto-statics, fluids, etc.
Papers sent by email as a zip file.
14 Nov. 7, 2022: Adjoint method of sensitivity analysis; and using the Lagrangian
Sensitivity of dynamic compliance; electro-thermal-elastic analysis Nov. 9, 2022: Reversal of the sequence of design sensitivity of adjoint variables in electro-thermal-elastic problems;
Coupled multi-physics problems: electrostatic-elastostatic
Verification of sensitivity using finite-difference methods and its pitfalls and remedy
Coupled electrostatic and elastostatic problem
Topology optimization of coupled electrostatic and elastostatic problem
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15 Nov. 14, 2022: Taking variation with vector and other shorthand notation
COMSOL overview and demonstration; explanation of HW4 and PA2 problems
Nov. 16, 2022: Topology optimization with COMSOL
Sensitivity analysis: parameter, shape; 1D and 2D; Jacobian and its derivatives (material and space derivatives)
Taking variation when there is shorthand notation with vectors
Parameter sensititvity of a functional
Shape derivative with a 1D example
Derivatives of the Jacobian and its other forms
Shape optimization in 2D
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16 Nov. 21, 2022: Homogenization; SIMP; topology optimization
TopOpt, YinSyn; optimality criteria method
Discussion for project-cum-programming assignment, term paper
Nov. 23, 2022: Topological derivatives and their use
Convex linearization leading to the method of moving asymptotes (MMA)
Homogenization of a 1D problem
Topological derivative
Optimization with topological derivative
Instructions for the term paper
Project presentation template
ConLin, MMA, and GCA papers
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Lecture notes of 2022 offering of this course

Lecture notes of 2021 offering of this course

Lecture notes of 2020 offering of this course