HERE 2 GNSS Module for Pixhawk

The here 2 GNSS module is the latest GPS module desgiend for use with ardupilot systems.  Compared the the first generation the Here V2 adds a 10 DOF IMU, F3 MCU running ChibiOS, along with all new RGB LED’s, and CANBUS capability.  The new HERE2 modules provide an optimised solution for the ever-changing customer requirements; with enhanced reliability and future customisation.

Key Features

• Concurrent reception of up to 3 GNSS (GPS, Galileo, GLONASS, BeiDou)
• Industry leading –167 dBm navigation sensitivity
• Security and integrity protection
• Supports all satellite augmentation systems
• Advanced jamming and spoofing detection

Here2 vs Here+ V2

With built-in STM32F302 microprocessor, running ChibiOS (a real-time operating system), which enables user defined features along with supporting firmware updates:

The STM32F302 is a high-performance microprocessor, with an innovative core and peripherals.

1. Outstanding performance – embedded Cortex
2. Powerful software support with feature-rich software packages
3. Comprehensive technical documentation

The HERE2 runs an open architecture based on the ChibiOS Real-Time Operating System (RTOS), and code from the Open Motor Drive project (OMD).  The inbuilt bootloader allows users to customize the code and add features according to their requirements. Hex / ProfiCNC via OMD will actively update the firmware and add more functions to exploit the full potential of the hardware.

Out of the box HERE2 supports standard serial port + I2C transmission data, just plug it in as you did the previous unit. With support for CAN bus on the way, the HERE2 can be switched through the built-in mechanical switch and included CAN cable.

CAN data transmission mode provides powerful technical support for Distributed Control System, to realize real-time and reliable data communication between each node. As the most commonly used communication protocol in the automotive industry, CAN bus has the advantages of strong real-time data communication, high reliability, flexible application and redundant structure. CAN allows for a distributed Autopilot system by placing components at their optimal position on an airframe without the worry of signal degradation.

The HERE2 utilises the UAVCAN bus protocol specifically developed for drone applications. UAVCAN has the following features:

1. A completely democratic communication structure with no master nodes; each node has the same communication rights, avoiding single-point failures.
2. Long payload data and complex data structures can be transmitted between nodes. UAVCAN can automatically decompose, transmit and reassemble complex data at the protocol level to prevent users from solving the problem at the application level.
3. High data throughput, low latency, suitable for application scenarios with high real-time requirements.
4. Supports redundant nodes and redundant interfaces, suitable for safety-critical drone applications.

A complete IMU including an accelerometer, compass and gyro can meet the diverse needs of the user for navigation. Combining barometer and GPS data, users could potentially run a separate EKF navigation system inside HERE2/HERE+ V2 to implement navigation tasks that are completely independent of flight control.

Four independent and customizable ProfiLEDs can be set according to user needs. Unlike the previous generation, HERE2/HERE+ V2 allows each LED to be controlled independently, therefore the user can define greater colour patterns to indicate more specific flight status (subject to code capabilities).

The HERE2 is a comprehensive upgrade of previous-generation product, suitable for industrial applications with higher security and reliability requirements, such as outdoor long-distance autonomous missions, security inspections, agricultural plant protection and more. The open source architecture and code are also suitable for developers who have specific needs for navigation functions and need in-depth development based on existing navigation features.