Components System
The RTK Surveyor was created to partner with low-cost, off the shelf devices. Here we’ll describe how to construct a Rover and Base.
Rover
Found here is the popular RTK Rover set-up. A monopole created for cams can be used. A cell phone owner try clamped with the monopod plus the RTK Surveyor is actually attached. The ?” camera bond with the monopole is modified to ?” 11-TPI and a L1/L2 antenna was affixed. A Male TNC to men SMA cable links the antenna on the RTK Surveyor. No broadcast is necessary because RTCM modification information is offered by a phone over Bluetooth.
We’ve got accomplished a lot of testing together with the u-blox L1/L2 antenna and it’s excellent for all the rate and dimensions. Mounted to a ground plate you will get good results. It’s simply a little ungainly when mounted to the top of a monopole. I encourage the ‘ufo’ preferences L1/L2 antennas because they have actually a larger antenna element and a slightly larger ground jet versus u-blox antenna.
If you are searching for a monopole (aka monopod), acquire one that is 65” in total or greater to make sure that the antenna would be above your mind. We’ve got good luck using the Amazon basic principles brand name.
We highly recommend against utilizing a strict helical antenna arrangement as revealed below. The RTK Surveyor is certainly not designed for such options and can create permanent problems for the antenna connector. The helical antenna becomes a big lever supply. If unit is actually fallen this lever is capable of harming the SMA connector and where in fact the connector is actually soldered toward PCB.
If you’re buying a mobile phone clamp make sure you buy one definitely appropriate for the latin dating apps diameter of monopole and has now a knob to improve clamp stress. The monopole are 27mm in diameter and we’ve got a knowledge about this clamp and this also clamp. Your own mileage can vary greatly.
In case you are getting RTCM modification data over a broadcast link it is best if your affix a broadcast with the again on the RTK Surveyor.
Picture-hanging pieces from 3M make a pleasant semi-permanent mount. Plug the 4-pin to 6-pin JST cable added to the RTK Surveyor from the broadcast interface to either on the Serial Telemetry Radios (transported in pairs). We really like these radios since they’re matched out of the container, either can submit or get (therefore it does not matter which broadcast try attached to base or rover) and they’ve got amazing range. We reached over a mile selection (almost 1.5 miles or 2.4km) making use of the 500mW radios and a huge 915MHz antenna on the base (discover this tutorial for more information).
Temporary Base
A temporary or mobile base build becomes necessary when you are in that particular niche too far away from a modification provider and/or cellular reception. A second RTK Surveyor are installed to a tripod plus its configured to accomplish a survey-in (aka, find it self), next begin broadcasting RTCM modification information. This data (
1000 bytes an extra) is distributed for the owner’s attached broadcast of preference. In regards to our functions, the 915MHz 500mW telemetry radios are employed because they offer understanding generally a serial cable tv between our base and rover.
Any tripod with a ?” camera bond will work fine. The Amazon Essentials tripod is very effective adequate but is a bit lightweight and rickety. A mobile phone holder is actually clamped toward tripod and the RTK Surveyor is actually used from inside the clamp. The ?” digital camera thread try adjusted to ?” 11-TPI and a L1/L2 antenna are connected. A Male TNC to Male SMA adapter links the antenna to your RTK Surveyor.
When the base has become build with an obvious look at the sky, push the set-up switch to “Base” and rotate the unit on. The reddish LED will blink for 60-120 seconds. Once the survey is complete the red LED would be continuously illuminated and RTCM facts will start to end up being shown. You are able to confirm this by looking at the LEDs from the telemetry broadcast (a small reddish LED will blink when serial information is was given from the RTK Surveyor). The RTK Surveyor was designed to follow the u-blox recommended survey-in of 60s and a mean 3D regular deviation of 5m of most solutions. If a survey fails to achieve these criteria it’s going to auto-restart after ten minutes.
Costly surveyor bases has a ?” 11-TPI bond but the the surface of the surveyor base will often hinder the antenna’s TNC connector. Should you decide decided to utilize a surveyor’s ‘stick’ be sure to obtain a ?” stretcher plate to raise the antenna about an inch.
If you’re buying a cell phone clamp be sure to get one definitely appropriate for the diameter of one’s tripod and contains a knob to increase clamp stress. Our tripod are 18mm in diameter and we’ve have an effective experience with this clamp. Their mileage may vary.
Note: a cellular base facility works well for quick travels toward field. However, the survey-in technique is not recommended your greatest reliability measurements since the positional accuracy for the base will directly convert with the accuracy in the rover. Stated in different ways, in case your base’s calulcated position is actually off by 100cm, thus will every reading your own rover helps make. If you’re finding optimum precision consider installing a static base with repaired antenna. We were able to identify the antenna at the top of SparkFun with an incredible precision +/-2mm of precision using PPP!
