Introduction to the sections about adding more hardware Pro Preview

TL;DR.

We are going to add three more things to the Raspberry Pi board, so place it to be accessible, or be prepared to open and close your car all the time.

Adding more hardware

We are about to add our first sensor to the car - a simple button. With that button, you can interact with your programs or with your car. You will have to attach to F-F cables to the Rasberry board and that might mean that you will have to open your car again.

Actually, three more times in total, because we are going to add two more sensors after that, so brace yourselves.

Why didn't you say so in the first place

Because our approach is for you to be constantly achieving milestones. That is why when you got the rear motor working, you made tests without the front motor. 

Now you had the whole car working and you wrote some python. That is a milestone. Next ones will be using the button and the Ultrasonic sensor.

A word about modularity

There is something important for us to mention. When you are designing things or considering how to close the car, placing the Raspberry and the power bank, you must be always considering future improvements and how to integrate them into your decisions.

So you had a valuable lesson in engineering design here if your car has trouble accessing the Raspberry board.