topic Re: Navigate to shapefile points in Developers Questions

Navigate to shapefile points

SRC_BOCCGIS_Department — Wed, 16 Dec 2015 20:32:34 GMT

I
have a question and wanted to see if maybe someone might help me find an answer.

WWe have a pending project for our
Public Works Department. We have created a shapefile of locations in a
thickly wooded area….they want to use the gps unit (Trimble GeoXH running
ArcPad 10) or another mobile device, to allow a bulldozer operator to navigate
to each of the points in the shapefile to create a path through this
area. I have tested both the methods of navigation, here in our parking
lot…the “Query and Go To” method using the binoculars and selecting the record
then clicking go to…..And the “Go To Selected” method, where you click on the
point you want to go to and then choose Go To Selected Feature.

Both
of these methods proved very frustrating to us, as you really don’t know which
way to go due to the arrow jumping all around. All I’ve read says it only
works when you are moving, and it did seems to improve slightly when we walked
really fast….However that will not be possible for the dozer operator. He
will have to find the starting point and it will be slower due to the amount of
undergrowth that he will be pushing.

I
hope I’ve explained this OK…..Does anyone happen to know of any additional options,
methods or apps we could use for them to make this a more feasible
project? We’d greatly appreciate your input and opinions.

Re: Navigate to shapefile points

ChrisSmith7 — Wed, 16 Dec 2015 21:05:41 GMT

Years ago, when I worked with environmental surveyors, I used waypoints, kinda like they do here - http://www.dot.state.mn.us/bridge/pdf/hydraulics/waypointstoreinspectexistingfeatures.pdf

The arrow direction varies and is not correct all the time. Think of playing the game “you’re getting warmer” and follow the distance or the symbols on the map view.

That was definitely true, but for people on foot, it got the job done. Maybe this will help you?

http://www.arcgis.com/home/item.html?id=7f0797450c4b470a8c76eb52b5eddaa8

Re: Navigate to shapefile points

DarrenWiens2 — Wed, 16 Dec 2015 21:05:58 GMT

Unfortunately, "thickly wooded area" automatically means that you're going to face additional challenges. I know they want to rely on GPS, but sometimes flagging is the best option.

Some things you can try to improve your accuracy:

- use GLONASS satellites, in addition to GPS (it looks like your unit does, but not sure if it does by default)

- elevate the antenna

As for the compass, you can get units with an internal electronic compass that does not require movement to work.

Re: Navigate to shapefile points

ChrisSmith7 — Wed, 16 Dec 2015 21:14:30 GMT

This is old, but someone did a write-up on GPS results under canopy:

http://www.proaxis.com/~johnbell/guest/GPS_Canopy_Tests.pdf

http://www.fs.fed.us/t-d/pubs/pdfpubs/pdf01712809/pdf01712809dpi300.pdf

Also, maybe something like this would help?

Trimble - Heavy Civil Construction - MS992 GNSS Smart Antenna