topic Re: Need Help using "Go To" or "Find" Features in ArcPad Questions

Need Help using "Go To" or "Find" Features

TonyCarricaburu — Thu, 20 May 2010 17:11:59 GMT

Im having difficulties using the "Go To" or "Find" feature to get me back to the points I made in the field. Im using a Trimble GeoXH with Arcpad 8. The small compass at the bottom bounces around and never seems to settle on a direction or distance. Any tips on using these features would be greatly appreciated. I just want to be able to pin point features I located before.

Thanks

Tony

Re: Need Help using "Go To" or "Find" Features

TonyCarricaburu — Tue, 25 May 2010 22:30:48 GMT

Can anybody help me out here?

Re: Need Help using "Go To" or "Find" Features

BrettBlack1 — Wed, 02 Jun 2010 23:23:25 GMT

Once you have marked a point on your map screen or marked it in the find features utility, the bearing and distance as well as the compass should efficiently guide you to the feature you are trying to navigate. If the GPS is not "settling" you make want to check your settings to be certain you are utilizing SBAS corrections and actually achieving real-time sub-meter accuracy.

If you are at a scale of approximately 10 meters or 30 feet and your cross-hair is bouncing around considerably then I would guess that you are not utilizing SBAS or real-time sub-meter corrections and need to check your GPS settings on the hardware.

Brett

Re: Need Help using "Go To" or "Find" Features

TonyCarricaburu — Thu, 03 Jun 2010 19:10:02 GMT

Brett,
Thanks for responding. I verified the settings on our GeoXH and it is using SBAS real-time correction. I went out into the field this morning to do some more testing with the same results. The compass bounces around 360 degrees. Never seeming to settle for more than a second. The red-line on the compass however seems to be pointing in the right direction if it could only figure out which direction was north. In other words if I position myself south of the point im trying to locate the redline remains near the North arrow and bouces with the compass.

Any other suggestions?

Thanks

Tony

Re: Need Help using "Go To" or "Find" Features

BrettBlack1 — Fri, 04 Jun 2010 01:22:29 GMT

The redline indicates the bearing or direction you need to walk in order to navigate to the feature in question. The compass is based on the GPS. So if you are standing still, the GPS is unable to determine which direction you are facing, so you need to be moving in order for the compass to register and get on track for a true direction.

I hope this clears it up.

Brett

Re: Need Help using "Go To" or "Find" Features

TonyCarricaburu — Tue, 08 Jun 2010 20:59:23 GMT

Brett,
That definitely fixed my compass issue. Thanks! Now I just need to perfect the methods of using the GoTo Tools to make them useful. I have yet to have been very successful in getting back to a previously (Diff. Corrected) point from a prior checkout session.

For example: Lets say I captured a point of a fire hydrant location (Diff. Corrected with a good PDOP indicating less than 16" after post processing). When I use the GoTo tool to direct me back to that hydrant it gets me within approx. 10ft. of where the hydrant actually is...

Im trying to understand how we can use this tool more effectively when the point captured isn't something we have the luxory of visually seeing like a paved over valve can...

Re: Need Help using "Go To" or "Find" Features

BrettBlack1 — Thu, 17 Jun 2010 16:08:58 GMT

When you stated that you are differentially correcting the data, are you post-processing? If so, what coordinate system are you post-processing your data in or exporting to?

When you navigate back to points are you using SBAS for real-time accuracy or are you tied into a VRS/RTN reference network?

10' off is quite a bit, and seems to be more than a coordinate system issue. Is 10' just an example or is this an average for most features?

Brett

Re: Need Help using "Go To" or "Find" Features

TonyCarricaburu — Thu, 24 Jun 2010 19:10:02 GMT

Brett,
Sorry for delayed response, I wasn't notified of any reply's to this thread.

To answer the questions in your response. Yes we are post-processing. The coordinate system we use is NAD_1983_StatePlane_California_V_FIPS_0405_Feet. And we are using SBAS not VSR although we may later look into the VSR option in our area.

The 10-ft off was an average at that time. Lately my field test have gotten me within 5 or more feet from our Navigation points. This has been done by capturing the highest accuracy points indicating 7" of accuracy after post-processing. I would assume this unit & antenna should get us within a 1-ft area and thats what were interested in achieving.

Thanks

Tony