Range Report GPS Range Finding with FFS Delta IV

[onetoe]

Lindy,

I was talking with Frank and he said that you have, as with most other things figured out how to do GPS ranging with the FFS Delta IV program. I am using the Trimble Nomad and it has built in GPS. When I hit the start button and go to devices it shows me as connected to GPS receiving raw data but when I go to the satellites it should show me longitude, latitude, bearing and altitude, I get no data transfer, nor to any other parts of the program except the GPS button is lit blue, indicating data is being received. I'm not very well versed in this subject, so its taken me awhile to get to where I am right now. I would appreciate your help or anybody else if you can provide any feedback.

 

[onetoe]

Re: GPS Range Finding with FFS Delta IV

So I got the GPS on the nomad to process the raw data and actually list the longitute, latitude, and altitude information. I am having a issue moving to the next step. How would the FFS Delta IV program use this information to conduct ranging? Would I need an external rangefinder to feed the data of my target or would I need to by some sort of maps program and try to estimate where my target is? As always, I would appreciate all help/feedback.

 

[one shot ST]

Re: GPS Range Finding with FFS Delta IV

using FFS..... you can do this:

the gps of the NOMAD give you your actual position, with this you can create a FFP.

with compass, range finder and ACI.... for example in the field direct range you can put:

bearing 340°
distance 670 m
angle/cousine..... .70

than if you tag calculate coordinate.... you can find as final result the coordiante of your target.....

second example..... if you know your target coordinate.. you can put them in map ranging..... and you find the distance......

if you have the version IV you can connect a laser range finder like a PLRF 10 C..... and with a simple click..... you got everythings.... distance, coordinate, ballistic solutions....

 

[CoryT]

Re: GPS Range Finding with FFS Delta IV

When the GPS button shows blue, the position data is not yet accurate. Once enough sats are locked, it will turn gray and the position info will be good. The Nomad does seem to take a few minutes to lock enought sats for a position.

You can now do a few things. First, you can create an FFP file for your current location, or just use the position data as the current FFP. Next, if you go to a target location, you can create a target file for that spot. You can also create target location from map data. From wherever you can see the target, you can set your FFP location and it will give you range, bearing and angle info to that target location. Selecting a target from the list will populate the main page and generate a solution.

If you have a range finder and compass, or a supported rangefinder with serial data output, you can give range and bearing to a target get the location, which you can save as a file if you like. With the rangefinder connected, it gives you the solution when you range.

 

[Lindy]

Re: GPS Range Finding with FFS Delta IV

And if you are going to create FFP position data from a GPS, and target data from a map, ensure that the GPS and the map use the same datum.

 

[one shot ST]

Re: GPS Range Finding with FFS Delta IV

FFS use WGS 84

 

[Lindy]

Re: GPS Range Finding with FFS Delta IV

<div class="ubbcode-block"><div class="ubbcode-header">Quote:</div><div class="ubbcode-body">FFS use WGS 84</div></div>

Umm, I don't think so.

FFS is independent of the datum being used. It is only important that the datum specified in the GPS being used agrees with the map datum, if data is being mixed in the system.

In addition, you can create ranging errors by having GPS data in the system created by GPS data from different datum.

Most GPS systems allow you to specify the map datum and/or coordinate system being used.

 

[one shot ST]

Re: GPS Range Finding with FFS Delta IV

Yes..... I know, but there is no field to change datum in FFS, I wrote in the past to Blaine and the answer was that with FFS you have to use WGS 84.... this is what they said.

also if you want to find coordinate of a target below your FFP... the altitude will be always higher.... because they said that negative cousine angle is not contemplated.

 

[CoryT]

Re: GPS Range Finding with FFS Delta IV

Well, most GPS units default to WGS84. FFS does not actually know what datum is being used, but if you mix coordinates you'll get incorrect ranges. WGS84 is pretty much identical to NAD83, but you'll still find a lot of North American maps with NAD27. MyTopo.com will do custom mapsheets to any desired datum, so I just order maps keyed to WGS84 and drive on.

 

[Lindy]

Re: GPS Range Finding with FFS Delta IV

<div class="ubbcode-block"><div class="ubbcode-header">Quote:</div><div class="ubbcode-body">FFS does not actually know what datum is being used, but if you mix coordinates you'll get incorrect ranges.</div></div>

Which was - and is - my point.

 

[one shot ST]

Re: GPS Range Finding with FFS Delta IV

your point is correct..... nothings to say about it... if you take coordinates from map, you have to use the same datum.....

I've used a lot of GPS, I thinks Garmin are the best.... actually I'm waiting a NOMAD L800 PDA, I don't know if is it possible to change datum there... Actually I'm using another PDA with FFS and I do not have any possibility to change datum. So map datum of a map must agree with gps datum.....

 

[one shot ST]

Re: GPS Range Finding with FFS Delta IV

to close the loop this is was the author of FFS wrote in the last e mail

"For the GPS functionality, I depend upon third party software, and it doesn't have the ability to change datums - or, at least the last time I dealt with the issue it didn't. They did come out with a subsequent major version release that may have added this functionality, but that company is now defunct. While I would like to have the ability to change datums, and at some point probably will, it is one of those things that will have to wait. If I change to the newer version of the GPS software, the change cause many, many parts of the software to break because the newer version was not backward compatible with what I am using.

So, it is a major project to update the GPS functionality and will have to wait until later. WGS 84 is it for the time being."

 

[Col Kurtz]

Re: GPS Range Finding with FFS Delta IV

BOW6.5, I don't mean to highjack your tread, but I was planning on getting the Trimble GPS card for my Trimble Recon. I also use FFS Delta IV. Does anyone have any experiance rangeing with this set-up?

Thank you in advance for your help.

 

[one shot ST]

Re: GPS Range Finding with FFS Delta IV

I'm using a NOMAD L800 with FFS versio IV, works great, Blaine from FFS wrote to me that NOMAD is better than RECON.... and I choose the first one.

 

[onetoe]

Re: GPS Range Finding with FFS Delta IV

No problem Col Kurtz. This is a little over my head and I'm trying to gain an understanding of the application. Any information I can pick up is helpful and much appreciated.