Project Overview

This repository contains an Android Remote Control application developed as part of a larger robotics project involving a robot navigating a maze. The Android application serves as a wireless Bluetooth interface for the robotic system. It allows a user to control the robot’s movement, monitor its status, and visualize the robot’s position and environment using a 2D grid-based map. The application communicates with an external robotic module (e.g. Raspberry Pi / AMD tool) via Bluetooth.

Project Scope

Within the scope of this project, the Android application is responsible for:

• Acting as a Bluetooth remote control for the robot
• Sending string-based commands to control robot movement
• Receiving status and coordinate updates over a Bluetooth serial link
• Rendering the maze environment and robot position on the UI
• Supporting persistent, user-configurable command strings

Core Features

1. Bluetooth Serial Communication

Transmits and receives text-based messages over a Bluetooth serial link to communicate with the robotic module.

2. Bluetooth Device Discovery & Connection

Provides a graphical interface for scanning, selecting, and connecting to nearby Bluetooth devices.

3. GUI-Based Robot Movement Control

Enables interactive control of robot movement using GUI elements such as buttons, which send predefined commands over Bluetooth.

4. Robot Status Display

Displays the current robot state (e.g. stopped, moving) using selective status information on the user interface.

5. Touch-Based Waypoint & Start Coordinate Selection

Allows robot start coordinates and waypoints to be selected through touch interaction on the grid-based map and transmitted over Bluetooth.

6. 2D Grid-Based Maze Visualization

Renders a 2D grid map showing obstacles, the robot’s position, and its heading.

7. Manual & Automatic Grid Updates

Supports both user-triggered manual updates and automatic background updates of the maze visualization based on received state changes.

8. Persistent User-Configurable Commands

Allows users to configure predefined command strings via the UI, which are stored persistently and retained across application restarts.

9. Robust Bluetooth Connectivity Handling

Handles temporary Bluetooth disconnections gracefully and resumes communication when the connection is re-established.

10. Arrow Block Rendering on Grid Map

Updates the grid map by replacing obstacle cells with arrow blocks when coordinate-based commands are received.

Lessons Learnt

• Practical Android application development using Activities, Fragments, and Services
• Integration with Android Bluetooth API for device discovery, connection management, and data exchange
• Event-driven UI updates using Handlers and listeners to react to external state changes
• Custom UI rendering with GridView adapters for dynamic, state-based visualization
• Touch-based user interaction for spatial input within a custom grid interface
• Use of persistent storage to retain user-configurable command strings across app restarts
• Defensive handling of intermittent connectivity without blocking or crashing the UI