Rapid switching between GPS receivers can cause real problems.
Switch if:
1) secondary GPS has 1 more satellite for at least 20 seconds
OR
2) secondary GPS has 2 more satellites for at least 5 seconds
Fixes https://github.com/diydrones/ardupilot/pull/2320
DRIVER FEATURES:
- All logic for RTK vs Normal now lives inside Piksi
- Supports observation uplink through telem radio
- Supports full SBP packet logging
- Reports high-rate green blinking to indicate RTK lock.
- Switchable to accept only Float or Integer RTK locks.
THIS REQUIRES PIKSI FIRMWARE v0.14 OR HIGHER
- Uses Piksi's new Pseudo-Absolute-Positioning mode
- Onboard Piksi must have Pseudo-Absolute mode enabled
- Ground Station Piksi must have a surveyed location in settings
- Ground Station Piksi must send its location to Onboard Piksi.
NEXT STEPS REQUIRED:
- EKF needs to take higher accuracy GPS into account
- EKF needs to take GPS RTK height into account
- GCS needs to support sending SBP observation packets
--- MAVProxy patch forthcoming
to ensure the GCS knows that we have lost the GPS we need to keep
reporting GPS_RAW_INT messages when the GPS disappears. Sending at 1Hz
should be sufficient
Fixes issue #1722
GNSS modules handled by PX4 drivers are not auto-detectable, some are not even
connected to a UART port. The activation is therefore controlled by GPS_TYPE
only. Baud rate and port settings (if applicable) have to be handled by the PX4
firmware.
This only works for the centralised builder, the modified Arduino IDE
will still include the NMEA and SIRF drivers meaning it will require
approximately 4k additional flash which may push us over the limit on
the APM2. Users will instead need to exclude other features to get
below the APM1/2 flash limit.
This is the SBP driver for Piksi, Lodestar and other forthcoming Swift Navigation GPSes.
This driver currently implements three things:
- Implements a lightweight SBP protocol detection system
- Implements Piksi as a single-point-positioning GPS (same as ublox/others)
- Implements hardware logging of GPS health and baseline messages
Forthcoming iin future updates:
- Need to implement the RTK functionality
This is a complete rewrite of the GPS driver structure, with a static
main driver and separate backend drivers. This will allow proper
support for multiple GPSes, and will allow parameters to be set on the
GPS object