Your Robot Car contains more than just the mechanical components we reviewed. The real magic happens in the hardware. Hardware refers to the physical components that make up a robot, such as the sensors and other devices that allow the robot to sense and interact with its environment.

Let’s learn a bit about what each bit of hardware looks like and what it does.

Raspberry Pi 3B/3B+/4B

This is the main computing component, acting like the “brain” of the system. It is its own little computer!

Robot HAT

A Robot HAT is a circuit board that can be attached to a Raspberry Pi computer to add extra functionality for building a robot.

The Robot HAT has several components on it, including:

• An MCU (microcontroller unit) which is a small computer that can be programmed to perform tasks and control other devices. The MCU on the Robot HAT is used to extend the PWM output and ADC input capabilities of the Raspberry Pi. (PWM output allows the Raspberry Pi to control the speed and direction of motors, while ADC input allows it to measure analog signals, such as those produced by sensors.)
• A motor driver chip which is used to control the motors on the robot.
• A Bluetooth module which allows the Raspberry Pi to communicate with other devices using Bluetooth.
• An I2S audio module which allows the Raspberry Pi to play audio.
• A mono speaker which is a single speaker that can be used to play sound.

The Robot HAT also has connections (called GPIOs) that allow it to be connected to the Raspberry Pi and access the Raspberry Pi’s input/output pins.

Ultrasonic Sensor

An ultrasonic sensor is a device that uses sound waves to measure distance or detect the presence of objects.

3ch Gray Scale Sensor

This device can be used to detect and follow a line on a surface. It works by using three channels, or sensors, that measure the intensity of light reflecting off the surface.