Software Engineering

6. SWE Structure, Packages etc.

Our system is built on a robust and modular software architecture that is designed for scalability and ease of use.

We use a publish-subscribe (pub-sub) architecture based on MQTT for communication between the UWB anchors and the central processing unit. This decoupled approach allows for a flexible and scalable system where anchors can be added or removed without affecting the overall system. The use of MQTT also allows for a high degree of interoperability.

The following UML diagram illustrates the MQTT communication between the different processes:

MQTT UML Diagram

Modular Design

The entire system is designed in a way that it is easy to extend. The core functionalities are divided into three distinct layers:

Hardware Layer: Interacts with the UWB hardware. This layer is responsible for configuring the UWB modules and reading the raw sensor data.
Communication Layer: Handles data transfer using MQTT. This layer is responsible for publishing the sensor data from the anchors and subscribing to it on the central processing unit.
Processing Layer: Performs the PGO calculations and other optimizations. This layer is where the magic happens. It takes the raw sensor data from the communication layer and turns it into a high-precision location estimate.

Python Packages

We have packaged the core functionalities of our system into easy-to-use Python packages. This allows developers to quickly integrate our localization middleware into their own applications with just a few lines of code. The packages are designed to be side-effect free and simple to use.

Here’s an example of how to bring up the system:

# Configure MQTT with your laptop's IP
mqtt_config = MQTTConfig(
    broker="192.168.68.66",  # Replace with your laptop's IP
    port=1884
)

# Start server
server = ServerBringUp(
    mqtt_config=mqtt_config,
    window_size_seconds=1.0
)

try:
    server.start()
    print("Server started. Waiting for anchor connections...")
    while True:
        if server.user_position is not None:
            print(f"Current position: {server.user_position}")
        time.sleep(1)
except KeyboardInterrupt:
    server.stop()

This simple and intuitive API makes it easy for developers to focus on building their applications without having to worry about the complexities of the underlying localization technology.

6. SWE Structure, Packages etc.

Publish-Subscribe Architecture

Modular Design

Python Packages