Autonomous Cleaning Robot

Overview

This project is a Java-based navigation system for autonomous cleaning robots operating within a defined rectangular grid. The solution focuses on reliability, strict boundary control, and a clear separation of concerns.

Architecture & Design

The application is built using Clean Architecture and Hexagonal (Ports & Adapters) principles to ensure the core logic remains independent of external interfaces.

Key Architectural Decisions:

• Hexagonal Architecture: Decouples core logic from infrastructure. The domain remains pure, while the application layer orchestrates use cases.
• Rich Domain Model (DDD): Business rules and validations are encapsulated within domain entities to ensure state consistency.
• TDD Approach: Developed with a test-first mindset, resulting in high coverage and a reliable, verifiable codebase.
• SOLID: Adheres to clean code standards, specifically leveraging Dependency Inversion for flexible adapter management.

Assumptions & Logic

• Boundary Safety: To protect the hardware, the robot will not execute a movement command if it leads outside the grid. In such cases, a DomainException is raised, and the current command sequence is terminated.
• Sequential Processing: Each robot finishes its entire instruction set before the user is prompted to deploy a new one.
• Collision Management: The current version focuses on single-robot navigation safety. Multi-robot collision avoidance is identified as a candidate for future development.

Navigation Commands

The robot processes a sequence of instructions. Any invalid characters or movements that would result in a boundary violation are caught and reported.

• L: Rotate 90° Left
• R: Rotate 90° Right
• M: Move forward one point in the current orientation

Note: Commands are case-insensitive.

Technical Stack

• Java 23: Core SDK
• JUnit 5: unit and integration testing
• Gradle 8.x: for build management

How to run

1. Clone the repository.

2. Ensure you have Java 17+ installed.

3. Run the application using Gradle:

    ./gradlew build

   or

   ./gradlew run --console=plain

4. Run the test:

   ./gradlew test

Future Improvements

• Stateful Grid: Multi-robot coordination ✅ - added
• Obstacle Mapping: Support for non-passable cells ✅ - added