Introduction

1.1 Background and Motivation

The development of surveillance robots has become a rapidly growing area of interest due to their wide-ranging applications in security, industrial monitoring, home automation, military operations, and border surveillance [1][2]. Traditional surveillance systems, such as closed-circuit television (CCTV), are often stationary, require extensive wiring, and lack mobility. In contrast, mobile surveillance robots offer the flexibility to navigate and monitor areas from multiple angles and locations [3].

The advent of low-cost, integrated microcontroller-camera modules like the ESP32-CAM has revolutionized the field of surveillance robotics. The ESP32-CAM module combines a powerful ESP32 microcontroller with a camera sensor, Wi-Fi, and Bluetooth connectivity in a compact form factor [4]. This integration allows developers to create wireless surveillance robots without requiring additional microcontrollers or complex hardware interfaces.

1.2 Problem Statement

Traditional surveillance systems face several limitations: lack of mobility resulting in fixed coverage areas, extensive wiring complexity requiring significant infrastructure, high cost for professional systems, limited real-time remote viewing capabilities, and dependence on manual human monitoring.

1.3 Objectives

The primary objectives of this work are: (i) to design a low-cost, Wi-Fi-controlled surveillance robot using the ESP32-CAM module; (ii) to implement live video streaming for real-time remote monitoring; (iii) to enable remote control of robot movement via smartphone or computer; (iv) to integrate a pan-tilt mechanism for adjustable camera angles; and (v) to develop a user-friendly web interface for controlling the robot.

1.4 Paper Organization

The remainder of this paper is organized as follows: Section II reviews related work. Section III describes the proposed system architecture. Section IV presents the software implementation. Section V discusses results and applications. Section VI concludes the paper.

2. Literature Review

Significant research has been conducted in IoT-based surveillance, wireless robot control, and home automation. Sri Lakshmi and Padma [1] presented an IoT-based smart surveillance system with intrusion detection capabilities. Adaramola [2] implemented wireless CCTV using IP camera technology. Balla and Jadhao [5] developed an IoT-based facial recognition security system with alerts. van Der Werff et al. [6] created a mobile-based home automation system using GSM technology. Alheraish [7] designed a GSM-based home automation system with microcontroller control.

Gu and Kim [8] proposed a UPnP-based surveillance camera system for home security. Wireless sensor-based remote control of mobile robots using Bluetooth and Sun SPOT technology was demonstrated [9]. An economical solution for wireless robot control systems was presented [10]. Surveillance robot using Arduino with camera integration was developed [11], while IoT-based surveillance robot with wireless camera control was demonstrated [12]. Border surveillance robot systems [13] and military surveillance robots for spying applications [14] have also been explored.

The present work differentiates itself by providing a complete, low-cost implementation of a Wi-Fi-controlled surveillance robot using the ESP32-CAM module with pan-tilt camera control and live video streaming capabilities, all accessible through a simple web browser interface.

3. Proposed System Architecture

3.1 System Overview

The proposed Wi-Fi-controlled surveillance robot integrates the ESP32-CAM module for both control and video streaming, an L298N motor driver for motor control, a pan-tilt servo assembly for camera positioning, and rechargeable batteries for power. The system connects to a local Wi-Fi network, allowing users to control the robot and view live video from any smartphone or computer with a web browser.

Fig. 1. Block Diagram of Wi-Fi Controlled Surveillance Robot

3.2 System Operation

The system operates as follows: (i) The ESP32-CAM module creates a Wi-Fi access point or connects to an existing network; (ii) The user connects their smartphone or computer to the same network; (iii) The ESP32-CAM streams live video to a web interface; (iv) The user sends movement commands (forward, backward, left, right) through the web interface; (v) The ESP32-CAM processes commands and controls the L298N motor driver; (vi) The motor driver regulates power to the DC motors for robot navigation; (vii) Servo motors adjust the camera angle for optimal viewing.

3.3 Circuit Diagram

*The circuit diagram shows connections between the ESP32-CAM module, L298N motor driver, servo motors, battery, and DC motors.*

Fig. 2. Complete Circuit Diagram of Wi-Fi Controlled Surveillance Robot

4. Software Implementation

4.1 Arduino IDE

The Arduino Integrated Development Environment (IDE) is an open-source software platform used to write, compile, and upload code to Arduino-compatible boards, including the ESP32-CAM [6][7]. The IDE is available for Windows, Linux, and macOS operating systems. The environment consists of three main sections: Menu Bar (File, Edit, Sketch, Tools, Help), Text Editor (for writing code), and Output Pane (displays compilation messages and errors) [7].

Fig. 3. Arduino IDE Interface

4.2 Installation and Setup

Step 1: Download Arduino IDE: The software can be downloaded from the official Arduino website. Users should select the version compatible with their operating system.

Step 2: Install ESP32 Board Support: To program the ESP32-CAM, users must add the ESP32 board URL to the Arduino IDE preferences and install the ESP32 board package via the Boards Manager.

Step 3: Select Board and Port: After installation, users select the appropriate board (AI-Thinker ESP32-CAM) and the correct COM port from the Tools menu.

Fig. 4. Board Selection in Arduino IDE

4.3 Code Structure

The ESP32-CAM surveillance robot code includes the following key components:

1.       Wi-Fi Configuration: SSID and password setup for network connection.

2.       Web Server Setup: HTTP server for video streaming and command reception.

3         Motor Control Logic: Functions for forward, backward, left, right, and stop commands.

4.       Servo Control: PWM signals for pan-tilt mechanism (0° to 180° rotation).

5.       Video Streaming: Camera initialization and streaming over Wi-Fi using MJPG format.

4.4 Web Interface

The system hosts a simple web page that displays the live video feed and provides on-screen buttons for controlling robot movement and camera angles. The interface is accessible from any device with a web browser, requiring no additional app installation.

5. Results And Applications

5.1 System Performance

The Wi-Fi-controlled surveillance robot was successfully implemented and tested under various conditions. Key results include:

·         Live Video Streaming: The ESP32-CAM provided real-time video streaming at 640×480 resolution with 15–20 frames per second over Wi-Fi.

·         Remote Control: Users successfully controlled robot movement (forward, backward, left, right) from a smartphone or computer within Wi-Fi range (approximately 30–50 meters line-of-sight).

Table 1. Performance Summary

·         Pan-Tilt Operation: Servo motors provided smooth 180-degree pan and 90-degree tilt movement for comprehensive camera positioning.

·         Battery Life: The robot operated for approximately 45–60 minutes on a single 7.4V Li-ion battery charge.

·         Response Time: Command response latency was approximately 100–200 milliseconds.