Has anyone found a way to change the sigma confidence reporting in Trimble Access? It displays errors to 1 sigma and I'd like 2 sigma. I asked a Trimble tech support guy and he said he's never heard of such a thing and would get back to me. I'm not optimistic. I'm still waiting on a return call from him from August, 2014 about a Trimble M3.
I don't believe it's possible. You can set it on whatever you want in TBC though.
ssorcbor, post: 352818, member: 1963 wrote: Has anyone found a way to change the sigma confidence reporting in Trimble Access? It displays errors to 1 sigma and I'd like 2 sigma. I asked a Trimble tech support guy and he said he's never heard of such a thing and would get back to me. I'm not optimistic. I'm still waiting on a return call from him from August, 2014 about a Trimble M3.
What equipment are you using? What's up with the M3?
SurveyAK, post: 353141, member: 9968 wrote: What equipment are you using? What's up with the M3?
Just to add, if it's Fixed/Float RTK, you're only ever going to be at 68% in the field. If you process after in TBC, you'll be at 95%. The only receiver at 95% in the field is the R10.
We're using R10's. I know you can set it in the receiver but will that show in Access? We're trying to dummy proof our equipment. It's pipeline. I know the difference and many of the other supervisors do but explaining to the field guys is pointless. A few will get it but most won't. It's a magic box that stores a point.
Nothing's up with the M3's. I figured it out a couple of hours after my call to tech support. I was pointing out that I wasn't expecting a call back after my last "difficult" problem. They were new and no one had ever used one. There was no cable, no manual, and in an area with poor cell coverage so we couldn't download one. We were trying to Bluetooth pair a TSC3 and the M3.
ssorcbor, post: 353149, member: 1963 wrote: We're using R10's. I know you can set it in the receiver but will that show in Access? We're trying to dummy proof our equipment. It's pipeline. I know the difference and many of the other supervisors do but explaining to the field guys is pointless. A few will get it but most won't. It's a magic box that stores a point.
Nothing's up with the M3's. I figured it out a couple of hours after my call to tech support. I was pointing out that I wasn't expecting a call back after my last "difficult" problem. They were new and no one had ever used one. There was no cable, no manual, and in an area with poor cell coverage so we couldn't download one. We were trying to Bluetooth pair a TSC3 and the M3.
how do you set it in the receiver? is it in the web interface somewhere?
ssorcbor, post: 353149, member: 1963 wrote: We're using R10's. I know you can set it in the receiver but will that show in Access? We're trying to dummy proof our equipment. It's pipeline. I know the difference and many of the other supervisors do but explaining to the field guys is pointless. A few will get it but most won't. It's a magic box that stores a point.
Nothing's up with the M3's. I figured it out a couple of hours after my call to tech support. I was pointing out that I wasn't expecting a call back after my last "difficult" problem. They were new and no one had ever used one. There was no cable, no manual, and in an area with poor cell coverage so we couldn't download one. We were trying to Bluetooth pair a TSC3 and the M3.
The HDGNSS engine runs at 1.96 Sigma / 95%. I have no idea how or why you would change it.
SurveyAK, post: 353172, member: 9968 wrote: The HDGNSS engine runs at 1.96 Sigma / 95%
That is the correct factor for 95% on a 1-dimensional measurement. For a 2-dimensional (e.g. horizontal) measurement with equal sigma on each axis, 95% confidence is at 2.445 sigma. If the sigma is different on the axes, the computation is more complicated - see Wolf & Ghilani.
SurveyAK, post: 353142, member: 9968 wrote: Just to add, if it's Fixed/Float RTK, you're only ever going to be at 68% in the field. If you process after in TBC, you'll be at 95%. The only receiver at 95% in the field is the R10.
I'm pretty sure that you don't know what you are talking about. Fix/Float is based on the likelihood of the integer number of cycles from the satellites between the base and rover being correctly resolved. The confidence level of the likelihood is set by the software, sometimes accessible to the user. Typically this likelihood is at 2 or even 3 sigma. The 1 sigma values you refer to are RMS precision estimates and aren't directly related to fix status. Most software reports precision at 1 sigma. Javad has places that show 1 and some that show 2. Sometimes this precision is the epoch by epoch precision. Sometimes, particularly while collecting a point, this precision is based on the cumulative spread of the individual epochs. No doubt the R10 is a fine machine. But you keep stating technical specifications that are in error.
As Bill said, a 2D RMS can be multiplied by 2.44 to get 2 sigma 2D estimates. For the vertical multiply by 2.
This white paper somewhat describes the difference between the RTK engine in the R10 and in previous receivers:
http://www.trimble.com/globalTRLTAB.asp?nav=Collection-92137
I'm not crazy about it because it's more a marketing piece than a scientific description of the technology. I saw a paper a couple years ago that went into more detail about the convergence process and how it differed from the traditional float / fixed solution, but I can't find it now. I seem to remember that it has to do with weighting each possible integer combination in the search region rather than trying to narrow down to one set of fixed integers, which results in better precision in poor conditions and more reliable reporting of the error estimates.
Bill93, post: 353206, member: 87 wrote: That is the correct factor for 95% on a 1-dimensional measurement. For a 2-dimensional (e.g. horizontal) measurement with equal sigma on each axis, 95% confidence is at 2.445 sigma. If the sigma is different on the axes, the computation is more complicated - see Wolf & Ghilani.
Thanks for clarifying.
Lee D, post: 353671, member: 7971 wrote: I seem to remember that it has to do with weighting each possible integer combination in the search region rather than trying to narrow down to one set of fixed integers, which results in better precision in poor conditions and more reliable reporting of the error estimates.
You are correct. This also eliminates the RMS value since the bad integer candidates, likely caused by multipath, can be discarded.
ssorcbor, post: 353149, member: 1963 wrote: We're using R10's. I know you can set it in the receiver but will that show in Access? We're trying to dummy proof our equipment. It's pipeline. I know the difference and many of the other supervisors do but explaining to the field guys is pointless. A few will get it but most won't. It's a magic box that stores a point.
I wouldn't take my chances at changing anything on the back end. Just make sure your pipeliners "Reset RTK" and you should be fine.
I remember the first time I was handed a level run that started at the bottom of the page... I understand and feel your pain.
ssorcbor, post: 353149, member: 1963 wrote: Nothing's up with the M3's. I figured it out a couple of hours after my call to tech support. I was pointing out that I wasn't expecting a call back after my last "difficult" problem. They were new and no one had ever used one. There was no cable, no manual, and in an area with poor cell coverage so we couldn't download one. We were trying to Bluetooth pair a TSC3 and the M3.
The "virtual" Serial Port and COM Port in the Bluetooth setup is typically missed and isn't spelled out well.
SurveyAK, post: 361076, member: 9968 wrote: You are correct. This also eliminates the RMS value since the bad integer candidates, likely caused by multipath, can be discarded.
Again RMS statistics for a position have nothing to do with integer ambiguities.