Robot Fleet Backend System

🛠️ Project Brief: High-Efficiency Robot Fleet Manager (C)

Project Overview

This project is a Production-Grade Robot Fleet Management System written in C. It is designed to simulate the backend infrastructure required to manage a fleet of autonomous warehouse robots. The system handles real-time data management, hardware-level status monitoring, and spatial collision avoidance.

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Core Technical Pillars

Dynamic Memory Management

• The system uses a dynamic array of robot structures.
• It utilizes malloc, realloc, and free to scale the fleet size at runtime.
• Optimization: Deletions are handled via memmove to shift memory in $O(1)$ allocation cycles, followed by a single hardware-level realloc to shrink the array, preventing memory thrashing.

Hardware-Aware Architecture

• Struct Packing: Uses __attribute__((__packed__)) to eliminate compiler-injected padding. This ensures the binary data is consistent across different CPU architectures (e.g., x86 vs. ARM).
• Bitwise Status Monitoring: Uses a uint8_t bitmask to store and toggle hardware states (Engine, Lights, Alarms) in a single byte of memory.

Advanced Algorithms (Spatial Hashing)

• Replaced a standard $O(N^2)$ brute-force distance check with an Amortized $O(N)$ Spatial Hash Map.
• The warehouse is mathematically divided into a grid. Robots are mapped to "buckets" based on their $(X, Y)$ coordinates.
• Collision Detection: The system only calculates distances between robots sharing the same grid sector, drastically reducing CPU cycles as the fleet scales.

Binary Persistence (Persistence Layer)

• Implements a custom binary file I/O system (fleet_data.bin).
• On boot, the system reads the fleet count and raw struct data directly into RAM.
• On shutdown, it flushes the current state back to the disk, ensuring full persistence between sessions.

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Functional Features

• Fleet Report: Decodes bitwise hardware statuses into human-readable logs.
• Modify Fleet: Allows for adding/deleting robots and toggling specific hardware bits via XOR (^) operations.
• Deployment Sorter: Uses the standard library qsort with a custom comparator function to sort the fleet by battery level in $O(N \log N)$ time.
• Emergency Protocol: A safety routine that identifies low-battery robots, forces their engines/lights OFF, turns their Alarms ON, and re-sorts the fleet for priority charging.

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Security & Safety Implementations

• Input Validation: Uses a custom get_safe_int function to prevent buffer overflows and handle non-integer input gracefully.
• Memory Safety: Includes explicit checks for realloc failures and ensures all allocated memory (including the spatial grid) is freed before the program exits or returns from functions.
• Data Sanitation: Uses strcspn to strip newline characters from user-entered strings, ensuring the binary save file remains clean.

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🚀 How to Compile and Run

1. Clone the repository:

   git clone https://github.com/Udith-Praveen/Robot-Fleet-Backend-System.git

2. Navigate to the directory:

   cd Robot-Fleet-Backend-System

3. Compile the multiple files using GCC:

   gcc -o fleet_manager main.c Robot_fleet_manager.c

4. Run the executable:

   ./fleet_manager