Robot Control with Web Interface

This project enables control of a robot with obstacle avoidance and a robot arm through a web interface using an ESP8266/esp32. The controller connects to Wi-Fi and accepts HTTP commands to manage the motor, robot arm, and sensors.

Features

Main

• Wi-Fi Control: Control the robot over a Wi-Fi network using a web interface.
• Obstacle Avoidance: Uses ultrasonic sensor data to automatically avoid obstacles.
• Robot Arm Control: Manage various robotic arm movements, including a gripper, base rotation, and joint movements.
• Configurable Speed: Set motor speed through the web interface.
• Position Management: Save and execute robot arm positions, along with predefined actions like scanning, picking, and waving.
• Motor Control: Forward, backward, turn, and stop commands.
• mDNS Support: Access the device using a hostname (e.g., http://serbot.local).

Parts

Body Control

• Directional Movement
  • Forward/Backward movement
  • Left/Right turns
  • Rotate left/right
  • Emergency stop
• Speed Control
  • Adjustable speed via slider (0-255)
• Obstacle Avoidance
  • Enable/Disable obstacle avoidance
  • Autonomous navigation mode

Arm Control

• Joint Control
  • Base rotation (left/right)
  • Shoulder movement (up/down)
  • Elbow movement (up/down)
  • Gripper control (open/close)
• Pre-defined Movements
  • Home position
  • Scan position
  • Pick object
  • Drop object
  • Wave gesture
• Position Memory
  • Save up to 3 custom positions
  • Load saved positions
• Command Recording
  • Record movement sequences
  • Play recorded sequences
  • Clear recordings

Hardware Requirements

• ESP8266 (NodeMCU or similar) or ESP32
• Motor Driver (L298N recommended)
• Ultrasonic Sensor (HC-SR04)
• Servos (for robot arm joints and gripper)
• Power Supply (suitable for motors and servos)

Pin Configuration

The table below lists the GPIO configurations for ESP8266 and ESP32. The board selector in the code (bool isESP32) should be set to true for ESP32 and false for ESP8266.

Motor Controller Pins

Component	ESP8266 GPIO	ESP8266 Alias	ESP32 GPIO	ESP32 Alias	Description
Motor 1 IN1	GPIO5	D1	GPIO25	IO25	Motor 1 Direction Control Pin 1
Motor 1 IN2	GPIO4	D2	GPIO26	IO26	Motor 1 Direction Control Pin 2
Motor 2 IN1	GPIO0	D3	GPIO27	IO27	Motor 2 Direction Control Pin 1
Motor 2 IN2	GPIO2	D4	GPIO14	IO14	Motor 2 Direction Control Pin 2
Motor 1 Enable (ENA)	GPIO14	D5	GPIO12	IO12	PWM pin for Motor 1 speed control
Motor 2 Enable (ENB)	GPIO12	D6	GPIO13	IO13	PWM pin for Motor 2 speed control

Ultrasonic Sensor Pins

Component	ESP8266 GPIO	ESP8266 Alias	ESP32 GPIO	ESP32 Alias	Description
Trigger Pin	GPIO13	D7	GPIO32	IO32	Trigger for distance measurement
Echo Pin	GPIO15	D8	GPIO33	IO33	Echo to receive distance

Robot Arm Pins

Component	ESP8266 GPIO	ESP8266 Alias	ESP32 GPIO	ESP32 Alias	Description
Base Servo	GPIO16	D0	GPIO17	IO17	Base rotation control
Shoulder Servo	GPIO3 (RX)	RX	GPIO18	IO18	Shoulder joint control
Elbow Servo	GPIO1 (TX)	TX	GPIO19	IO19	Elbow joint control
Gripper Servo	GPIO9	SD2 / S2	GPIO21	IO21	Gripper open/close control

Notes:

• Aliases for ESP8266: NodeMCU board pins (e.g., D1, D2) map to ESP8266 GPIO pins.
• Aliases for ESP32: Use IO followed by the GPIO number as a naming convention.
• Special Pins: GPIO9 (SD2 on ESP8266) and GPIO10 (SD3) are typically used for flash operations on ESP8266. Use these cautiously.
• PWM on ESP32: ESP32 supports multiple PWM channels, improving servo control and motor speed adjustment.
• UART Pins: Be aware of RX/TX pins (GPIO3 and GPIO1) if used for debugging or communication.

Ensure proper power supply and grounding to avoid performance issues or damage to the components.

Additional Notes for ESP32:

• The ESP32 supports more PWM channels and higher resolution, allowing smoother servo movements.
• Ensure pins for Trigger and Echo are free from internal pull-ups or pull-downs to avoid conflicts with the ultrasonic sensor.

Wi-Fi and mDNS:

• The project includes mDNS support for both ESP8266 and ESP32, allowing access to the web interface using the hostname http://serbot.local.

Code Modifications for Board Selection

• In the source code, ensure the following line is updated based on the board in use:

  bool isESP32 = true;  // Set to true for ESP32, false for ESP8266

This boolean configures the correct pin definitions and initializes the appropriate libraries for the selected board.

Quick Start

1. Connect the hardware as per the pin configuration table.
2. Flash the code to the selected board.
3. Access the web interface via http://serbot.local once the device connects to Wi-Fi.

Troubleshooting

• Connection Issues: Ensure Wi-Fi credentials are correctly configured, and the board is within range.
• Servo Jitters: Use a stable power supply for motors and servos, especially with ESP32 where higher currents may be drawn.

GPIO images

Software Requirements

• Arduino IDE with ESP8266 and ESP32 support.
• Libraries:
  • WiFi.h: For Wi-Fi connectivity (ESP32).
  • ESP8266WiFi.h: For Wi-Fi connectivity (ESP8266).
  • WebServer.h (ESP32) or ESP8266WebServer.h (ESP8266): For creating the HTTP server.
  • ESPmDNS.h or ESP8266mDNS.h: For mDNS service.

Hardware Requirements

• Microcontroller: ESP8266 or ESP32.
• Motors and Driver: L298N or similar motor driver.
• Ultrasonic Sensor: HC-SR04 or similar.
• Servos: For robotic arm control.
• Power Supply: Compatible with the microcontroller and motors/servos.

Setup Instructions

1. Clone Repository

git clone https://github.com/lily-osp/esp-robot-control.git
cd esp-robot-control

2. Select Your Board

Set the isESP32 boolean in the code to match your board:

• true for ESP32

• false for ESP8266

  const bool isESP32 = true; // Set to false if using ESP8266

3. Install Libraries

Ensure the required libraries are installed in the Arduino IDE:

1. Open Arduino IDE.
2. Install ESP8266 or ESP32 boards via the Board Manager.
3. Install additional libraries via the Library Manager.

4. Configure Wi-Fi

Update the ssid and password in the code with your Wi-Fi credentials:

const char* ssid = "YOUR_WIFI_SSID";
const char* password = "YOUR_WIFI_PASSWORD";

5. Upload the Code

1. Connect your ESP8266/ESP32 to your computer via USB.
2. Select the appropriate board and port in the Arduino IDE.
3. Upload the code.

6. Connect the Hardware

Wire the components to your microcontroller as per the pin definitions in the code.

7. Access the Web Interface

1. Open the Serial Monitor to find the assigned IP address.
2. Open a web browser and enter the IP to access the control interface.

Web Interface and Commands

The web interface provides buttons and controls for the following actions:

• Movement Commands: mv (move forward), bk (move backward), lt (turn left), rt (turn right), rl (rotate left), rr (rotate right), st (stop).
• Speed Control: spd [value] - Set the motor speed, where [value] is a number between 0-255.
• Obstacle Avoidance:
  • oa on: Enable obstacle avoidance mode.
  • oa off: Disable obstacle avoidance.
  • oa nav: Start navigation using obstacle detection.
• Robot Arm Commands:
  • b [dir]: Move base. dir can be f (forward), b (back), l (left), or r (right).
  • s [dir]: Move shoulder. dir can be u (up), d (down).
  • e [dir]: Move elbow. dir can be u (up), d (down).
  • g [dir]: Move gripper. dir can be o (open), c (close).
• Position and Recording:
  • stream: Start recording arm movements.
  • m pos [number]: Save current position as a specific number.
  • m save [number]: Move to a saved position.
  • m [action]: Perform predefined actions, e.g., home, scan, pick, drop, wave, etc.

UI preview

Left: Body Control Interface - Right: Arm Control Interface

Control Commands

Here’s the completed table with example usage for each command:

Category	Command	Description	Example Usage
Body Movement	mv	Move forward	http://<esp_ip>/command?cmd=mv
	bk	Move backward	http://<esp_ip>/command?cmd=bk
	lt	Turn left	http://<esp_ip>/command?cmd=lt
	rt	Turn right	http://<esp_ip>/command?cmd=rt
	rl	Rotate left	http://<esp_ip>/command?cmd=rl
	rr	Rotate right	http://<esp_ip>/command?cmd=rr
	st	Stop	http://<esp_ip>/command?cmd=st
	spd X	Set speed (X: 0-255)	http://<esp_ip>/command?cmd=spd%20150
Arm Movement	b +/-	Base rotation	http://<esp_ip>/command?cmd=b%20+ or cmd=b%20-
	s +/-	Shoulder movement	http://<esp_ip>/command?cmd=s%20+ or cmd=s%20-
	e +/-	Elbow movement	http://<esp_ip>/command?cmd=e%20+ or cmd=e%20-
	g o/c	Gripper open (o) / close (c)	http://<esp_ip>/command?cmd=g%20o or cmd=g%20c
Pre-defined Movements	m h	Home position	http://<esp_ip>/command?cmd=m%20h
	m s	Scan position	http://<esp_ip>/command?cmd=m%20s
	m p	Pick object	http://<esp_ip>/command?cmd=m%20p
	m d	Drop object	http://<esp_ip>/command?cmd=m%20d
	m w	Wave	http://<esp_ip>/command?cmd=m%20w
Position Memory	m pos X	Save position (X: 1-3)	http://<esp_ip>/command?cmd=m%20pos%201
	m save X	Load position (X: 1-3)	http://<esp_ip>/command?cmd=m%20save%201
Recording	stream	Start recording	http://<esp_ip>/command?cmd=stream
	done	Stop recording	http://<esp_ip>/command?cmd=done
	play	Play recording	http://<esp_ip>/command?cmd=play
	clear	Clear recording	http://<esp_ip>/command?cmd=clear
Obstacle Avoidance	oa on	Enable OA	http://<esp_ip>/command?cmd=oa%20on
	oa off	Disable OA	http://<esp_ip>/command?cmd=oa%20off
	oa nav	Auto navigation using OA	http://<esp_ip>/command?cmd=oa%20nav

User Interface

The interface features a modern, retro-styled design with:

• Responsive layout
• Tab-based navigation
• Touch-friendly controls
• Visual feedback
• Dark theme
• Intuitive icons
• Status notifications

Troubleshooting

• Cannot Connect to Wi-Fi: Double-check the SSID and password. Restart the ESP8266.
• Commands Not Working: Ensure all components are wired correctly. Check for any loose connections or power supply issues.
• Servo or Motor Issues: Verify that the power supply is adequate for servos and motors.

Common Issues

1. Can't connect to WiFi

   • Verify credentials
   • Check WiFi signal strength
   • Ensure ESP32 is powered properly

2. Commands not responding

   • Check serial monitor for errors
   • Verify IP address
   • Check network connectivity

3. UI not loading

   • Clear browser cache
   • Check browser console for errors
   • Verify all CDN resources are loading

Notes

• Power Considerations: Ensure that the ESP8266 has a stable 3.3V power supply. Motors and servos may require separate power sources if they draw significant current.
• Pin Limitations: The ESP8266 has limited PWM pins, so configure carefully based on your hardware setup.

License

This project is licensed under the MIT License.