I have been tasked with providing an estimate to profile about 20 miles of highway centerline (every 100' feet), and the work must be done during the night.
Does anyone have experience using RTK/GPS during the nighttime hours? Are there enough satellites over Texas during the late hours of the night to provide accurate GPS solutions?
I've done plenty of night work
I rather like it - calm and quiet
Get yourself a good headtorch, and a lantern plus spare batteries for both
Can't speak to Texas - But NZ gets sufficient satellites 24/7
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Yes, night time surveying can be done with GPS and Robots. No issue with satellites.?ÿ
I don't mean to be mean, but find it scary that an RTK user tasked with such a big project (over 1,000 shots) is unaware the GNSS constellations provide the same coverage day and night.
Well, asking questions is the best way to get to know more. The people I worry about are the ones who don't ask questions.
In the Olden days we could to do some planning to make sure that there were no satellite coverage issues, there were are lot less of them available.?ÿ Pretty much redundant now.
Trimble still have a tool, search gnss mission planning, link below
https://www.gnssplanning.com/#/settings
Find on your location, set date and time and apply.?ÿ Then look at tables, charts, sky plots, etc.
I would dig a bit to ensure you are using the right tools and methods for the task. This may be a perfect job for interval auto-topo or mobile scanner. Depends on the purpose..?ÿ
I haven't needed planning software for a long, long time. There will be plenty of satellites up after dark.?ÿ
Well, how you gonna see to work at night??
seriously....
night gps is better than day time work. No solar radiation, aka sunspots.?ÿ
Night work is good.?ÿ
N
I would dig a bit to ensure you are using the right tools and methods for the task. This may be a perfect job for interval auto-topo or mobile scanner.
For sure, drive that sucker! I've seen truck mounted receivers used to observe runways at 10 foot intervals, should be plenty good enough for highway at 100 foot intervals...
If there are no satellite coverage at night then waze, google earth and other navigarion apps wouldn't work and you would have heard a lot of complaints from pizza delivery customers. I know, someone is gonna say accuracy is not the same but they are still using the same satellite signals.
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True, but basic questions on big jobs...?
Bear in mind that if the highway is open to traffic you need GOOD illumination on yourself - and somebody with you, just in case. Are you on foot or in a vehicle?
When I started doing GPS in 1986, the satellite coverage was sparse, and in the winter you had to work at night, summer was in the daytime. Back then it was static only, and we usually did 2 or 3 hour sessions. Receivers were large and antennas were large. First ones I used required a generator and an antenna that was about 3' X 3'. And nobody had ever heard of GPS. So that made for some interesting interactions with law enforcement.?ÿ?ÿ
Not that I started out that quite that early, at least on a professional/civilian level, it was more like 92 with the 'smaller' 40000STs for me.?ÿ One fun thing about those days was starting your work night off meeting the crews down at the local pub since it was all that was open.
@chris-mills Traffic control is provided by the construction company, we will be in the suicide lane the whole way with a crash truck behind us. We will keep our survey truck with us as well.
Have you considered getting a rover rod truck door mount and just drive having the software store a point every so many feet? You would measure your offset down to pavement level
?ÿThey Had two 4000sse that they wanted me to sell at a place i was working at a few years ago.?ÿ They both actually booted up.
Those things were beasts.?ÿ I'm glad i never had to hump those through the mountains.?ÿ The 5700s with extra batteries survival gear and water with teh gravity meter was bad enough.
I still have a 4009ssi floating around somewhere.?ÿ The SSTs were considerably bigger than the sse/ssi but diminutive in comparison to the early models John is referring to.
The 4000sse and ssi are still useful for static (e.g., OPUS) or post-processed rapid static base-rover. They are limited to 9 GPS sats L1/L2 or 18 L1. You have to override the week number in converting to RINEX.
The big sst isn't good for much because it uses wave squaring. Under good signal conditions you can get an OPUS result, but the accuracy is very much inferior and not eligible for OPUS share.