I was in SE Wyoming two weeks ago (3/17-3/23) doing some boundary work with my locus units.
I had a base unit about 4 miles from the rover. Collected a static observation, initialized on that point & took 3-4 shots within 200' of the initialization point, 4 miles from the base.
All static shots processed very well; all kinematic failed by 3-10 feet. No tree cover, no obstructions, good sattelites as far as I could tell.
I was using a 5 second recording interval with a 60 second observation. I have read a few posts about recent sun-spot activity - could that have been part of the problem?
Anyone have any thoughts? It's a real drag to have to make a return trip to get 3-4 shots with the total station!
Jerry
Jerry,
How many sv's were you locked on to during your kinematic session?
J.D.
I'm a bit ashamed to admit that I don't really know - we'd been locked on 6-8 most of the morning. I had a PDOP forcast printout and we were still in good shape during the time of the kinematic shots. The alarm never sounded, so I plowed on ahead.
Jerry
Jerry,
Don't know about your specific problem but ....
1. www.spaceweather.com (from general board) might be a good source for all of ous to start factoring into the K equation.
2. Don't have any idea if this would have helped but when doing K, I switch everything to 2 second interval and use 60 second obs. time. The working time hasn't changed and I've recorded 2.5 times the data (old theory ..a little is good a lot is better)
Jimbo
Jerry,
High ionospheric activity, such as what has been detected recently, could cause you grief, even when our base and rover are separated by only 4 miles. This is especially true with kinematic surveys, since your observation times are so short.
Email your data to me. I can tell by looking at the raw data if it was ionosphere or some other factor that caused your survey to fail.
Bill Martin
Ashtech Precision Products
Bill-
Just sent that days obs to you - feel free to share the results with the board if it's something that might help others - just dont tell them about the "Eating Crow" part! ;^O)
Jerry
Jerry,
I just finished taking a look at your data and have made the following observations:
1. You certainly encountered some ionospheric activity during this survey. Using a new tool in Ashtech Solutions 2.0 (soon to be released update to Locus Processor), I was able to look at a plot of one of the raw data files. It showed the classic signs ionospheric activity (signal-to-noise plot looks like a sine wave).
2. The ionospheric activity coupled with the length of your vectors (5 miles from one base station, 9 miles from the other) seems to be the reason why Locus Processor was not able to produce solutions for this kinematic survey.
The good news is that Ashtech Solutions 2.0 was able to successfully process this data. We've made some improvements to the processing engine in this new version that helped in this instance. 95% uncertainties to kinematic points 0531 and 0532 were 0.15 ft on the 5 mile vectors and 0.20 ft on the 9 mile vectors. Holding fixed your same point (0101), Ashtech Solutions 2.0 produced the following coordinates for your 2 points (in SPCS83 Wyoming East):
0531 693431.038 716569.023 4691.999
0532 693429.227 716595.276 4690.591
Let me know how these positions compare to those computed from your conventional survey of these points.
Bill Martin
Ashtech Precision Products
Bill-
Coords match as follows:
0531 693431.038 716569.023 4691.999(You)
0531 693431.108 716568.986 ????(Me)
0532 693429.227 716595.276 4690.591(You)
0532 693429.223 716595.300 ????(Me)
Not too shabby for a 5-mile shot!
So when do we get 2.0?? (Can't wait!)
Thanks for taking a look at the data.
Jerry
2.0 sound like some amazing stuff. I hope the learning curve is fairly flat. The results from the 2.0 and conventional comparison may cause me to get the K kit out again.
Bill,
What part of the data will 2.0 allow to be modified in the kinematic mode to achieve these results? I need to prime my learning curve pump early. When you have the time (if you have the time) give us a few hints along the way of the improvements and the basic operating methods that will be used.
Jerry,
Good post. Got me all excited about the potential of Locus again.
Thanks Jerry and Bill
J.D.