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

Now, you can graph some NACA airfoils by name. But, there are many more airfoils in the UIUC database than just NACA ones. Let’s try graphing an MH70 airfoil:

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_4.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('     ')
                x_coordinates.append(float(x.strip()))
                y_coordinates.append(float(y.strip()))
            except ValueError:
                continue
                
    return x_coordinates, y_coordinates, plot_title


air_foil = 'mh70'
x_values, y_values, title = get_airfoil_coords(air_foil)
plot_airfoil(x_values, y_values, title)


It’s blank. Let’s look at the `.dat` file to see why:

```text
MH 70  11.08% 
  1.00000000  0.00000000
  0.99663874  0.00038973
  0.98681861  0.00160039
......
  0.98657712  0.00013332
  0.99660243  0.00006156
  1.00000000  0.00000000
```
The coordinates are separated by two spaces, not five. There are also leading spaces to the x coordinate, but the `strip()` method you call should take care of that. Some airfoil dat files have numbers greater than 1.0; in addition to casting the `str` as `float`, you should also make sure that the `float` is less than or equal to 1.0.  We need to re-write the `for` loop to handle any number of spaces separating the two coordinates. Fortunately, you can use the built-in `count()` method to count the number of spaces in the line, and you can use `str` multiplication to split the line by the number of spaces that `count()` counts.

Develop an airfoil plotter for all types of airfoil coordinates.

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

Standardizing Airfoil Coordinates