Usually autopilot triggers the camera and records the coordinate it has at the moment. When the drone is flying at 20 m/s and GPS works at 5 Hz, that means your autopilot will have position readings only each 4 m, which is not suitable for precise georeferencing. Also, there is always a delay between the trigger and the actual moment the photo is taken.
Reach solves the problem of positioning by connecting directly to the camera hot shoe port which is synced with the shutter. The time and coordinates of each photo are logged with a resolution of less than a microsecond. This method allows to use GCPs only to check your accuracy.
1. Connect Reach to a hot shoe port on a camera
Every time a photo is taken camera produces a pulse on a flash hot-shoe connector which is synced to a shutter opening.
2. Fly a drone, Reach will record photo events
Reach captures flash sync pulses with sub-microsecond resolution and stores them in a raw data RINEX log in internal memory.
3. Download logs from Reach and base station
After the flight get the RINEX logs from your airborne Reach module and a base station (Reach RS, CORS or other receiver).
4. Process logs and get a file with geotags of photos
Process RINEX files using the free RTKLIB software. Produced file with precise coordinates of the photos can be used for georeferencing.
To calculate centimeter precise coordinates in PPK and RTK, Reach needs corrections from a base station. It could be either another Reach receiver or NTRIP service. VRS is also supported.
Reach M2 and M+ work seamlessly with other Reach receivers over any link. Compatible with any other receiver that supports RTCM3 and NTRIP.
Reach M+ and Reach M2
and Reach RS+
If you work within short baselines then Reach M+ is an optimal choice.
and Reach RS2
Provides robust performance and quick initialization. Allows working on long baselines.
Up to 10 km
Up to 60 km
Up to 20 km
Up to 100 km
Up to 14 Hz
Up to 20 Hz
Reach M+ UAV mapping kit
Reach M+, Reach RS+ and GNSS antenna
Reach M2 UAV mapping kit
Reach M2, Reach RS2 and GNSS antenna
ReachView is the easiest to use software for data collection that is available both for Android and iOS. With ReachView, you can control all the features of Reach receivers, such as setting up a base station, logging RINEX data, configuring NMEA output, and monitoring data.
Reach is able to trigger cameras as well as register events. Event mark feature is a must for aerial mapping as it allows to register precise time when shutter was activated.
Logs are automatically recorded in internal memory directly to RINEX. View a list of the logs and download them using the ReachView app.
ReachView shows current satellite levels, your location on a map, and much more.
3DroneMapping completes PPK trials with the average zero mean error in all axes
Luke Wijnberg, 3DroneMapping
As a brief synopsis of the results, the maximum deviation of points was no more than 0.09m in all axis. This is an incredible result given the fact that the average pixel size of the resulting imagery was 0.045m. The average mean error in all axes is just few mm!
Tuffwing gets 4cm precision without GCPs with Emlid Reach RTK
Brian Christal, Tuffwing
Tuffwing recently performed integration of Emlid Reach RTK to enable making precision maps without use of GCPs. The system was benchmarked by comparing direct georeferenced model with a set of GCPs, used solely for error detection purposes. Achieved lateral RMS error is just 4cm according to the Pix4D quality report.
Event38 integrates Emlid Reach and starts providing ready-to-go PPK mapping solution
Jeff Taylor, Event38
In this case study, we produced an orthomosaic in the Drone Data Management System™ with 2.45cm horizontal and 5.08cm vertical RMSE, as compared with a survey-grade GPS on the ground.
ReachView app and all features of Reach receivers are included