Gain insights into using Python for mechanical and aerospace engineering. Learn about basics, graphing techniques, airfoil plotting, and dynamic pressure and orbital modeling in 2D and 3D.

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In this course, you will learn about the Python programming language in the context of mechanical and aerospace engineering. 

You will start with the basics of Python, like variables, collections, and different types of loops. Once you have the basics out of the way, the real fun begins. You will learn how to: graph thrust available and thrust required, graph dynamic pressure during a rocket launch, and how to plot airfoil coordinates. 

Towards the end, you will get a strong overview of orbital parameters and learn how to model both 2D and 3D static orbits. Once you’ve completed this course, you will have a better understanding of Python and how it works in the context of mechanical/aerospace engineering.

Python for Mechanical and Aerospace Engineering

What if you ask it to plot an airfoil that is not in the database?

import requests
import matplotlib.pyplot as plt


def plot_airfoil(x_coordinates: list, y_coordinates: list, plot_title: str) -> None:
    """
    Plot the airfoil coordinates given the list of coordinates

    :param x_coordinates: list of airfoil's x coordinates
    :param y_coordinates: list of airfoil's y coordinates
    :param plot_title: str to title as the plot's title
    :return: None
    """
    plt.plot(x_coordinates, y_coordinates, 'k-')

    plt.title('{} airfoil'.format(plot_title))
    plt.style.use('default')
    plt.xlim(-0.50, 1.25)
    plt.ylim(-1, 1)
    #plt.show()
    plt.savefig("output/chap4_6.png")


def get_airfoil_coords(airfoil: str) -> tuple:
    """
    Get airfoil coords from UIUC website
    https://m-selig.ae.illinois.edu/ads/coord/__.dat
    :param airfoil: str of airfoil types
    :return: tuple of ([x coords], [y coords], plot_title)
    """
    url = 'https://m-selig.ae.illinois.edu/ads/coord/{}.dat'.format(
                                                   airfoil.lower())
    response_text = requests.get(url).text
    
    all_text = response_text.split('\n')
    x_coordinates, y_coordinates = [], []
    plot_title = ''

    for index, line in enumerate(all_text):
        if index == 0:
            plot_title = line.strip()
        else:
            try:
                line = line.strip()
                x, y = line.split(' ' * line.count(' ')) # line changed
                x = float(x.strip())
                y = float(y.strip())
                if x <= 1.0 and y <= 1.0:                # line changed
                    x_coordinates.append(x)
                    y_coordinates.append(y)
            except ValueError:
                continue
                
        return x_coordinates, y_coordinates, plot_title


air_foil = 'not_an_airfoil_name'
x_values, y_values, title = get_airfoil_coords(air_foil)
plot_airfoil(x_values, y_values, title)


Oops, that is a little embarrassing. If you request a URL that does not exist, the website returns a webpage with a big, bold **Not Found** at the top. You can screen for this “not found” piece of text, and if found, you can raise an exception to alert that the airfoil requested did not exist. You could create a custom `Exception` or `Error`, but let’s just use the built-in `NameError` instead. 

In the `get_airfoil_coords()` function, you will add the following `if` statement after the `response.text` line:

```python
if 'Not Found' in response_text:
    raise NameError('{} not found in UIUC database'.format(airfoil))
```

Be careful on the capitalization since the website returns “Not Found” and not “NOT FOUND” or “not found.” In the main program, you can couch the script with a try-except clause:

```python
air_foil = 'naca2512'
try:
    x_values, y_values, title = get_airfoil_coords(air_foil)
    plot_airfoil(x_values, y_values, title)
except NameError:
    print('{} not in UIUC database, try again!'.format(air_foil))
```

Now you can handle any airfoil in the UIUC database, and you can also handle any fat-fingered typing that the user might input!


Getting Comfortable with Python

FizzBuzz

Graphing Thrust Available and Thrust Required

Graphing Dynamic Pressure During a Rocket Launch

Getting and Plotting Airfoil Coordinates

Modeling a 2-Body Orbit in 2D and 3D

Unit Conversions

Introduction to Web Scraping

Modeling Camera Shutter Effect

Writing Reports with Pweave

The End

Finishing the Airfoil Plotter