ESP8266 Robotics Projects

ESP-01 is a small Wi-Fi module based on Espressif ESP8266EX that can give any microcontroller access to a Wi-Fi network. The ESP-01 module (Figure 1.2) is the basic and the most popular board of the ESP8266 module family. You should have an ESP8266 ESP-01 module to understand the basics of ESP8266 and build robotics projects.

This is a list of vendors that typically stock the ESP-01 modules:

Figure 1.2: The original ESP8266 ESP-01. Image courtesy of SparkFun Electronics (https://www.sparkfun.com)

The original ESP8266 ESP-01 has the following features:

Here is a list of all the ESP8266 boards of the ESP8266 module family at the time of writing:

The top of the ESP-01 board consist of the following things:

Figure 1.3: ESP-01 top view

The original ESP8266 ESP-01 board has eight pins and comes without headers. You can solder regular wires with pins, but if you want to use it with a breadboard, you should attach headers:

Figure 1.4: ESP-01 pinout

The ESP8266 works only with regulated 3.3V. You can build a simple regulated power supply with an LD1117-3.3 linear voltage regulator. It can provide 3.3V at 800 mA. You can purchase a TO-220 package of the LD1117-3.3 for use with a breadboard. Figure 1.5 shows the circuit diagram for 3.3V output. You can supply 4-15V DC to V_in using one of the following sources:

Figure 1.5: 3.3V regulated power supply circuit diagram

Now, you can connect the power supply to ESP-01:

ESP8266 ESP-01 doesn't have a built-in USB to serial conversion chip to directly connect to your computer through a USB cable for flashing programs. As a solution, you can use a USB to TTL serial console cable to connect ESP8266 to a computer. Figure 1.6 shows a USB TTL serial console cable from Adafruit (https://www.adafruit.com/product/954):

Figure 1.6: A USB to TTL serial console cable. Image courtesy of Adafruit Industries (https://www.adafruit.com)

The type A USB plug includes a USB to serial conversion chip and provides four wires to connect to your ESP8266ESP-01 board. Table 1.1 shows the functions of the four wires:

Table 1.1: Color codes and functions of wires

You can use the following steps to connect the USB to TTL serial cable with your ESP8266:

The following steps will guide you how to use a serial terminal program to communicate and execute AT commands with ESP-01. In this example, you will use PuTTY, SSH, and a Telnet client for Windows to run AT commands through a serial port:

Figure 1.7: The PuTTY configuration window

Table 1.2 shows the complete set of AT commands that you can use with ESP8266:

Table 1.2: The ESP8266 AT command set (Source: SparkFun Electronics)

Every AT command starts with the letters AT. Here's an example:

AT+GMR <CR>

Type the AT command AT+GMR and press the Enter key. Don't type <CR>. The CR indicates carriage return.

This will return the firmware version ID of the ESP8266 module, as shown in Figure 1.8:

Figure 1.8: Terminal output for the AT+GMR command

Likewise, you can run any AT command with the PuTTY terminal to execute on ESP8266 through the serial connection.

The Arduino core for ESP8266 includes a set of libraries to do the following things with your ESP8266 Wi-Fi module:

It also allows you to write sketches for ESP8266 with the core Arduino functions and libraries. You can run the sketches directly on ESP8266 without using an external microcontroller board:

Figure 1.9: The Arduino IDE preferences

Figure 1.10: The Arduino IDE Boards Manager

Now, you will write your first program (sketch) for ESP8266 with the Arduino IDE to blink a LED connected to PIN 2 of ESP8266.

You'll need the following things to build the circuit:

Connect the components together, as shown in Figure 1.11:

Figure 1.11: The LED blink circuit hook up

#define ESP8266_LED 2void setup() {  pinMode(ESP8266_LED, OUTPUT);}void loop() {  digitalWrite(ESP8266_LED, HIGH);delay(500);digitalWrite(ESP8266_LED, LOW);delay(500);}

The 3-Layer Mini Round Robot chassis Kit (Figure 1.12) includes the following things you need to build the shell of a two-wheel drive mobile platform robot:

You can purchase a kit from Adafruit Industries (https://www.adafruit.com/product/3244) to work with projects that will be discussed in Chapter 2, Building a Mini Round Robot with Original ESP8266, Chapter 3, Using Encoders, and Chapter 4, Building a Mini Round Robot with the Feather HUZZAH ESP8266:

Figure 1.12: A Mini Round Robot Chassis Kit. Image courtesy of Adafruit Industries (https://www.adafruit.com)

The Zumo chassis kit (Figure 1.13) allows you to build tracked robots that run on continuous tracks instead of wheels. Tracked vehicles can be used for:

The Zumo chassis kit includes the following things:

You can purchase a kit from Pololu (https://www.pololu.com/product/1418) to work with the project that will be discussed in Chapter 5, Line-Following Zumo Robot:

Figure 1.13: A Zumo chassis kit. Image courtesy of Pololu (https://www.pololu.com)

The Romi chassis kit (Figure 1.14) includes the following things you need to build a two-wheel drive robot:

You can purchase a kit from Pololu (https://www.pololu.com/category/202/romi-chassis-and-accessories) to build the project that will be discussed in Chapter 6, Building an ESP8266 Robot Controller:

Figure 1.14: A Romi chassis kit - Black. Image courtesy of Pololu (https://www.pololu.com)

The mini robot rover chassis kit (Figure 1.15) includes the following things needed to build the shell of a two-wheel  drive robot:

Figure 1.15: A mini robot rover chassis kit. Image courtesy of Adafruit Industries (https://www.adafruit.com)

You can purchase a kit from Adafruit industries (https://www.adafruit.com/product/2939) to build the project that will be discussed in Chapter 7, Building a Gripper Robot.

The Rover 5 robot platform (Figure 1.16) allows you to build a four-wheel drive tracked robot. The kit includes the following things:

Figure 1.16: A Rover 5 robot platform. Image courtesy of Pololu (https://www.pololu.com)

You can purchase a kit from Pololu (https://www.pololu.com/product/1551) to build a project that will be discussed in Chapter 8, Photo Rover Robot.

The wheel encoder kit (Figure 1.17) allows you to measure the speed or distance that the chassis travels. You'll learn how to connect the wheel encoder kit to any wheeled robot in Chapter 3, Using Encoders:

Figure 1.17: A wheel encoder kit. Image courtesy of SparkFun Electronics (https://www.sparkfun.com)

A gripper can be connected to a robot to allow grip objects. Figure 1.18 shows a Parallel Gripper Kit assembled. You will need any standard size Hitec or Futaba servo to integrate with the gripper kit. You can purchase one from SparkFun Electronics (https://www.sparkfun.com/products/13178):

Figure 1.18: Parallel Gripper Kit A - Channel mount