Radio Telemetry Tracker Drone Communications Package (Comms Package)

The Radio Telemetry Tracker Drone Communications Package is a Python-based library designed to facilitate the transmission, reception, and handling of protobuf-based radio packets between a drone's field device software (FDS) and the ground control station (GCS). It implements reliable communication through packet acknowledgements, serialization/deserialization of Protobuf messages, and provides an extendable structure for new message types.

Note: This package is not intended for end-user use in standalone mode. Rather, it is a shared component that is consumed by the FDS and GCS repositories. Therefore, detailed user-facing instructions are provided in the respective repositories where this package is integrated.

Table of Contents

• Radio Telemetry Tracker Drone Communications Package (Comms Package)
  • Table of Contents
  • Overview
  • Prerequisites
  • Installation
  • Configuration
  • Usage
  • Troubleshooting
  • License

Overview

This package provides:

• Packet Definitions: Protobuf message definitions for radio telemetry data and requests
• Codec: Encoding/decoding logic with framing, CRC checks, and synchronization markers
• Radio Interfaces:
  • SerialRadioInterface: For physical serial (UART) connections
  • SimulatedRadioInterface: For TCP-based simulation and testing
• Packet Management: Reliable transmission with retry and acknowledgment (ACK) mechanisms
• DroneComms Class: High-level API with typed handlers and callback registration

Prerequisites

• Python 3.12 or later
• Poetry 1.8 or later
• For serial communication: pyserial
• For protocol buffers: protobuf, grpcio-tools

Installation

1. Add as a dependency to your project:

   poetry add git+https://github.com/UCSD-E4E/radio-telemetry-tracker-drone-comms-package.git

2. Or clone for development:

   git clone https://github.com/UCSD-E4E/radio-telemetry-tracker-drone-comms-package.git
   cd radio-telemetry-tracker-drone-comms-package
   poetry install

Configuration

The library supports two interface types:

1. Serial Interface:

from radio_telemetry_tracker_drone_comms_package import RadioConfig

config = RadioConfig(
  interface_type="serial",
  port="/dev/ttyUSB0", # Serial port
  baudrate=56700, # Communication speed
)

2. Simulated Interface (for testing):

config = RadioConfig(
  interface_type="simulated",
  host="localhost", # TCP host
  tcp_port=50000, # TCP port
  server_mode=False, # Client/server mode
)

Usage

Basic usage pattern:

from radio_telemetry_tracker_drone_comms_package import DroneComms, RadioConfig, GPSData

1. Initialize communications:

   config = RadioConfig(interface_type="serial", port="/dev/ttyUSB0")
   comms = DroneComms(radio_config=config)

2. Register handlers for incoming packets:

   def on_gps_data(data: GPSData):
     print(f"GPS: {data.easting}, {data.northing}, {data.altitude}")
   
   comms.register_gps_handler(on_gps_data)

3. Start communication:

   comms.start()  # Opens the radio interface and starts Rx/Tx threads

4. Send packets as needed:

   comms.send_sync_request(SyncRequestData())

5. Clean up when done:

   comms.stop()  # Closes the radio interface and stops threads

Troubleshooting

Common issues and solutions:

• No Packets Received

  • Check physical connections (serial) or network connectivity (TCP)
  • Verify correct port/baudrate settings
  • Look for exceptions in logs

• CRC Errors

  • Ensure matching Protobuf versions between FDS and GCS
  • Check for packet framing issues
  • Verify byte order consistency

• Timeouts

  • Increase read_timeout or ack_timeout for slow/unreliable links
  • Check for network congestion or interference
  • Verify both ends are running and properly configured

License

This project is licensed under the terms specified in the LICENSE file.