TFGPS01 - UAV GNSS Navigation Module with RTK Capability

TFGPS01 without enclosure

Overview

The TFGPS01 is a high-end precision GNSS navigation module designed for UAV applications. It features multi-constellation reception, high noise immunity, and RTK capability, making it suitable for various drone navigation and payload synchronization tasks. The module can operate as both a standalone UART GPS and a USB GPS receiver.

Key Features

  • Multi-GNSS Support: GPS, GLONASS, Galileo, and BeiDou.
  • RTK Capable: Achieves centimeter-level accuracy with an RTK-compatible module.
  • Compatibility: Works with PX4, Ardupilot, and other common flight stacks.
  • Integrated Safety Features: A beeper, safety LED, and an external safety switch connector are included.
  • Payload Interface: Allows time synchronization and geo-fencing capabilities.
  • High Noise Immunity: Optimized for RF-noisy environments with high-linearity and dynamic range LNA.
  • Daylight Visible LEDs: Status indicators for power, GPS, RTK, and safety features.

Handling Precautions

  • The TFGPS01 is a highly sensitive device; handle it with care.
  • Avoid direct contact with the antenna to prevent damage from sweat acids.

Compatible GNSS Receiver Modules

The module is by default equipped with:

High Noise Immunity

The ThunderFly TFGPS01 GNSS receiver is optimized for operation in RF-noisy environments using a high-linearity LNA at the RF input. This results in higher power usage and slightly lower sensitivity, which can be optimized for the specific application by adjusting R27 and R26 resistors.

Hardware

The TFGPS01 is designed as open hardware (GPL v3), and all documentation is available in the GitHub repository.

PCB Layout

Enclosure

A 3D-printed protective enclosure is available and customizable in OpenSCAD.

3D printed box

Mechanical Drawing

TBD

Connection Diagram

The TFGPS01 module can be connected simultaneously to an Autopilot and Payload. Below is a standard setup:

Typical connection of TFGPS01 to the autopilot and payload

Electronic Schematic

The full schematic is available as KiCAD project in repository and also in PDF preview.

LED Indicators

LED LabelDescription
ONIndicates 5V power in module
ARMSafety LED from autopilot
GEOGeofence status of uBlox
RTKRTK status of uBlox
TPLTimepulse from uBlox

Pinout

GPS & Safety Connector

PinNameDescription
1Vcc (+5V)Power for module
2RXData from Autopilot
3TXData from TFGPS01A
4I2C SCLI2C clock from autopilot
5I2C SDAI2C data from autopilot
6SAFETY_INSafety switch input
7SAFETY_LEDSafety LED signal
8VDD (+3.3V)Power for safety features
9BUZZERBeeper signal
10GNDGround

I2C AUX Connector

I2C AUX is I2C1 output from the autopilot. No other device is connected to I2C.

PinName
1+5V
2SCL
3SDA
4GND

Safety Switch Connector

PinNameDescription
1SAFETY_VCC+3.3V (low current)
2SAFETY_LEDSafety LED output
3SAFETY_INSafety switch input
4BUZZERBeeper signal
5+5VPower supply
6GNDGround

Payload Connector

The module is equipped with a connector designed for payload connection; this feature is useful for time-sync and navigation data, time-stamping, or geofencing.

The connector is labeled as Payload GPS Interface.

PinNameDescription
1TIMEPULSETime-pulse signal from uBlox GNSS receiver
2EXTINTInterrupt output from uBlox
3GEO_STATGeoStat output from uBlox
4SDAI2C from uBlox
5SCLI2C from uBlox
6RXRx of uBlox, parallel to the autopilot via a protective resistor
7TXTx of uBlox, parallel to the autopilot via a protective resistor
8GNDAutopilot GND

USB-C Connector

USB is connected directly to the uBlox module for configuration and testing. Configuration via u-center.

Technical Specifications

  • Dimensions: 50x50x11mm.
  • Weight: 31g.
  • Power Consumption: 40mA (without beeper active).

Availability

The TFGPS01A module is available for purchase from:

For more detailed documentation and open-hardware design files, refer to the GitHub repository.