2. Introduction to Evolutionary Algorithms
•Definition: Evolutionary Algorithms
(EAs) are optimization techniques
inspired by the process of natural
selection.
•Key Concepts:
•Population-based search.
•Genetic operations: selection,
crossover, mutation.
•Fitness function: measures how good
a solution is.
3. What is Algorithm?
An algorithm is a specific, step-by-step procedure or a set of
instructions designed to solve a problem or perform a specific task. It
outlines the logical steps needed to transform input data into desired
output, much like a recipe guides you through the steps of cooking. In
computer science, algorithms are essential for writing programs and
solving computational problems
4. Evolutionary Algorithms in Architecture
Evolutionary Algorithms are computer-based
problem-solving methods that are inspired by the
natural process of evolution – just like how
animals and plants evolve over generations to
survive better.
👉 In EA, designs evolve by trying different
versions, keeping the best ones, and combining
them to create new, better versions – like nature
does with genes.
5. 📌 How it works:
Start with a group of random designs (called a
"population").
Evaluate each design (based on some goal – like
least material, best ventilation, most sunlight,
etc.)
Select the best designs.
Combine them (crossover) and mutate them
slightly to make new designs.
Repeat the cycle to keep improving!
6. What is Evolutionary Art?
In art, evolutionary algorithms are used to create
patterns, paintings, or forms by evolving visual ideas
over time.
🎨 Example:
Imagine a computer generating a bunch of abstract
paintings. A designer picks the most beautiful one. The
computer then combines and modifies those to make
new ones. This cycle continues, and after many
generations, we get amazing artworks created
through evolution.
7. 🔍 Real Example:
Karl Sims is a digital media artist and visual effects software developer. His
interactive works have been exhibited worldwide including at the Pompidou
Center, Ars Electronica, DeCordova Museum, Boston Museum of Science, and the
National Museum of Mathematics. He founded GenArts, Inc. which created
special effects software tools for the motion picture industry, and he also held
positions at Thinking Machines Corporation, Optomystic, and Whitney/Demos
Productions. Karl studied computer graphics at the MIT Media Lab, and Life
Sciences as an undergraduate at MIT. He is the recipient of various awards
including two Ars Electronica Golden Nicas, a MacArthur "Genius" Grant, and an
Emmy Award.
9. Evolutionary Algorithms (EAs)**
Evolutionary Algorithms (EAs) in architecture
refer to the application of evolutionary principles
—such as selection, mutation, and crossover—used
in computational design processes to generate
innovative architectural solutions.
10. 1. Selection:
Selection is like choosing the best options from
a set of possibilities. Just like in nature, where
the fittest organisms are more likely to survive
and reproduce, in evolutionary algorithms, the
"best" solutions are chosen to continue to the
next generation.
Example:
Imagine you have several designs for a building.
The best design, based on criteria like space
efficiency or aesthetic appeal, is selected to
form the foundation of the next design.
11. “It is not the strongest of the species that survives, nor the most intelligent,
but the one most responsive to change.”
by Charles Darwin
12. Example from Nature
Giraffes live in areas with tall trees, so those with
long necks can reach the higher leaves and have a
better chance of surviving. There were two types of
giraffes in the past: long-necked and short-necked.
Long-necked giraffes had a survival advantage
because they could access more food and win
fights, leading them to breed more. Short-necked
giraffes, on the other hand, struggled to survive and
reproduce. Over time, the long-necked giraffes
became more common, and short-necked giraffes
went extinct. The mutation for long necks provided
a survival advantage in nature.
14. 2.Mutation
Mutation is a random change made to a design. It’s like introducing a small
new variation to a solution. This randomness helps explore new possibilities
and prevents the algorithm from getting stuck on one solution.
Example:
In architecture, imagine a building’s shape is slightly changed—maybe the
roof’s angle is adjusted or the windows are reshaped. This change might bring
unexpected improvements.
15. Example for Mutation
This mutation in architecture—
shifting from traditional to
sustainable design—has become a
survival advantage in a world
facing climate change and
resource scarcity. Just like in
nature, over time, this type of
design will likely become the
norm, as the benefits in terms of
environmental preservation, cost
savings, and occupant health
continue to prove its value.
16. 3. Crossover:
Crossover is like mixing the best parts of
two solutions. It’s inspired by how genes
combine during reproduction in nature.
The idea is to combine different "good"
parts of existing solutions to create a
potentially better solution.
Example:
Let’s say you have two building designs:
one with a fantastic layout and the other
with a great facade. Crossover would
combine the layout of one with the
facade of the other to create a new
design that might be even better.
18. How They Work Together:
Selection picks the best designs.
Crossover combines parts of these good designs.
Mutation randomly changes some aspects of the new
designs to explore new possibilities.
Through these processes, the algorithm keeps improving solutions (like
architectural designs) over multiple generations, just like how nature evolves
over time!
20. Genetic Algorithm
The Genetic Algorithm helps you find the best solution by
evolving your choices over time using a combination of
selection, crossover, and mutation. It’s like trial and error,
but smarter, and it gets better over time.
22. Example - Choosing the Best Vegetarian
Dish to Cook
Problem: Choosing the Best Vegetarian Dish to Cook for the WeekendLet’s say
you’re trying to choose which vegetarian dish to cook this weekend. You have
afew options in mind, but you want to make the best decision, something
exciting
23. Step 1 ( Different Solutions)
Representation of Solutions (Chromosomes)You have a list of vegetarian dishes
you are considering:
Dish 1: Vegetable Biryani
Dish 2: Paneer Butter Masala
Dish 3: Stuffed Paratha
Dish 4: Vegetable Stir-fry
Each of these dishes is like a chromosome in the Genetic Algorithm world. Each
dish is apossible solution to your weekend cooking decision.
24. Step 2: Initial Population
Initial Population Now, you start with your initial population. You could randomly
pick a couple of dishes, orjust pick all of them to begin with. For this example,
let’s say you randomly pick 4 options.Your initial options could be:
Dish 1: Vegetable Biryani
Dish 2: Paneer Butter Masala
Dish 3: Stuffed Paratha
Dish 4: Vegetable Stir-fry
25. Step 3: Fitness Function
Now, you need a way to rate or measure how good each dish is for the weekend.
Let’s makethe fitness function based on a few factors like:
1.How quick and easy is it to cook? (Easier dishes are
better!)
2.How much you like the dish? (Personal taste!)
3.How many ingredients do you have at home? (Less
shopping is better!)
27. You might give each dish a score out of 10 for each of these factors:
Vegetable Biryani: 8 (easy to cook, you like it, but needs some ingredients)
Paneer Butter Masala: 6 (takes more time, you like it but need extra
ingredients)
Stuffed Paratha: 7.3 (easy to cook, you like it, but it needs specific
ingredients)
Vegetable Stir-fry: 8.7 (quick and easy, you like it, and you have most
ingredients)
28. Step-4 Selection
you need to select the best dishes based on their fitness scores. You will
choose thedishes with the highest scores to move to the next step.
From the table,
Vegetable Stir-fry has the highest score (8.7), followed by
VegetableBiryani (8).
These will be selected to be the parents for creating new dishes.
29. Step 5: Crossover (Mating)
you combine features of the best dishes (mating) to create new dishes.
For example:
Parent 1: Vegetable Stir-fry (9, 8, 9)
Parent 2: Vegetable Biryani (7, 9, 7)
You can combine the best features of both:
Take the quick and easy part from Vegetable Stir-fry (9/10).
Take the taste from Vegetable Biryani (9/10).
Take the ingredients availability from Vegetable Stir-fry (9/10).
Now, your new offspring dish could be a quick and tasty stir-fried Biryani!
New Dish (Offspring): Quick Veg Biryani Stir-fry (combining both!)**
30. Step 6: Mutation
add mutation. Mutation is like making a small random change to try and
improvethe result.
For example, you might decide to try adding a new ingredient to the Quick
VegBiryani Stir-fry, like tofu or a new spice that you’ve never tried before. This is
the mutationstep.The new dish could be: Quick Veg Biryani Stir-fry with
TofuNow, this dish might have a slightly better taste or texture that could make
it even better thanthe original!
31. Step 7: Repeat
continue the process of evaluating, selecting, crossing over, and mutating
your dishes until you find the one that you’re most happy with. You might try
this over a few weekendsuntil you find the perfect weekend dish.
32. Summary
1. Initial Population: Choose a list of possible dishes to cook.
2. Fitness Function: Rate each dish based on factors like how easy it is to
cook, howmuch you like it, and how many ingredients you already have.
3. Selection: Choose the dishes with the highest fitness scores (best
options).
4. Crossover: Combine the best features of two dishes to create a new dish.
5. Mutation: Make small changes to try new things (like adding a new
ingredient).
6. Repeat: Continue testing and adjusting until you find the perfect dish.
By repeating this process, you evolve your choices and eventually pick the best
vegetarian dish for your weekend
33. Key Idea:
Genetic Algorithm helps you find the best solution
by evolving your choices over time using a
combination of selection, crossover, and
mutation. It’s like trial and error, but smarter, and
it gets better over time.