HeroLink: Industrial IoT Hub

The Challenge

In e-commerce logistics, manual entry of parcel dimensions and weight is a major bottleneck. It is time-consuming and prone to typos, which ultimately leads to costly shipping surcharges.

The goal of HeroLink was to create a “Plug-and-Play” station. The application orchestrates 4 peripherals simultaneously (1 scale + 3 lasers) to capture parcel data as soon as a barcode is scanned, then synchronizes the information with an ERP via an API.

Technical Choices

Why .NET 10 & Avalonia UI?

• .NET 10 & C#: I chose C# because .NET 10 allows for top-tier asynchronous performance, which is essential for handling multiple hardware data streams without latency.
• Avalonia UI: Chosen for its modern rendering engine and flexible styling system. As the natural successor to WPF, it provides a solid, portable foundation while remaining open to future cross-platform needs.

The Hardware Stack

Everything relies on System.IO.Ports for serial communication (COM):

• Scale: Real-time text/hex frame parsing to obtain stabilized weight data.
• Lasers (x3): Custom binary parser developed to extract distances (e.g., AA 00 00 20...) and convert them into actual dimensions after calibration.

The Problem: Serial Port Instability

During testing, the connection with the scale was inconsistent. After about ten minutes of inactivity, the port would stop responding. This occasionally blocked the main thread, causing the user interface to freeze.

The Solution: Multithreaded Management

To resolve this, I overhauled the communication architecture:

• Thread-Safety: Implemented SemaphoreSlim to orchestrate port access and prevent data write conflicts.
• Decoupling: Port reading is handled by background tasks to keep the UI responsive.
• Auto-reconnect: Added a “Watchdog” mechanism that detects timeouts and automatically restarts the connection.

Technical Deep Dive: API

I used Refit to transform the API into a strongly-typed C# interface:

• Security: Automatic API key injection into the HTTP pipeline.
• Robustness: Centralized error handling and JSON mapping via Newtonsoft.

Lessons Learned

• Mastering Avalonia: Discovered the framework’s resource lifecycle and the power of the MVVM pattern for complex interfaces.
• Industrial UX: In a warehouse, every second counts. The app is designed to be event-driven (responding to scans and weight stability), reducing manual interactions to the absolute minimum.

Retrospective

The project is currently in production. If I were to evolve it further, I would isolate the hardware logic into a separate Windows Service (Background Worker). The interface would then act as a light client communicating via SignalR, making data capture entirely independent of the UI state.