I was just playing in 2.4 and ran across an interesting "problem". Luckily I have one of those data files that has almost every improbable situation in it. Just lucky I guess.

It seems to me that files created with the HP can be used in a Continuous Kinematic mode, with a little care and planning.

If you have a kinematic session handy with an obs, with ID of ???? then give it a number, set it to kinematic and see what happens.....looks like CK to me.

Of course in the field you would need to keep very accurate records but points with "marker descriptions" could be used to wrap the CK session.

Such as point xxxx, description BEGIN 1, then run your pole along your line using the range pole wheel from Lo-Ink, then at the end save a point xxxx+1, description END 1, or something similar. Then when you process give the ???? between your BEGIN and END points a number for the range of points it will create.

Note the above is totally conjecture and has NOT BEEN TESTED BY ME !!!!!!!!

Jimbo


edit above in red
Modified By James Webb on 8/25/2001 at 11:05 AM

You may be right!

Just tried it, you input a site ID over one of those ????'s that appear between every pair of kinematic shots and the software asks for a range.

The only problem is that the points created remain raw, unprocessed, and have no vectors associated with them. Is that usual with CK processing?

I'm going to run a test today.

You guys might be on to something, but I think I would pass on trying to give a site ID to an unused epoch of data; my luck it would have been while the two meter pole setup was laid across my shoulder, with the bottom of the rod about 2' off the ground.
I really can't see where you could use the continuous kinematic deal unless you had the "wheel" set up, and then if you managed to lose lock, you would have to come "out" of the wheel fixture, reinitialize on a known point (that you didn't have because you were using the wheel), maybe like for a road centerline or a curb line it would be effective, but unless you are tying in a fence along a golf course, I just can't see it as a viable method of data collection.
On the other hand, if you were to affix the pole to a 4 wheeler and had a wide open pasture to topo, that would be pretty neat.

Dave,

Generally I agree with the limited use of CK. But the method of "wrapping" your CK run with points would eliminate the worry of using points recorded while on your shoulder.

I can see ways of avoiding the on/off of the wheel for re-init but haven't tried cuz I don't have a wheel yet.


Boy, having PK in with Ck would solve the loss of lock scenario. Just wishful thinking, not complaining.

But if you do lose lock hopefully 2.4 will work as Procesor in being able to set a static point in the middle of Kinematic session without much difficulty. Not sure about that. Might take some D-file editing.

Nearly, let us know what happens. When I hit F5 they processed with vectors written and F7 adjusted them.

Jimbo
Modified By James Webb on 8/25/2001 at 5:34 PM

I just completed a test.

I located 9000 feet of road centerline and profile in less than 20 minutes.

I started with a kinematic pt 0002, put the receiver on my truck roof, got in and started driving at a rate that produce a shot every 40 feet, which works out to roughly 6 miles per hour with 5-sec epochs.

When I got to the end I put the unit on a tripod, waited for 4 or 5 epochs, then logged a kinematic pt 0003.

Then I turned off the unit, and back on for a good static.

When processing, I first processed without the CK. It all checked out. Then I input the range, which came to 200 points. At this point they were raw. Then processed again, with all vectors meeting 0.2 criterion.

I noticed that the points created while the rover sat on the tripod matched the subsequent endpoint kinematic and static within 0.1, which seems to indicate a perfectly good session.

The next test will be on a known line. Notice that while this first test appears to have worked out, the actual centerline is not surveyed.

I think it works.

.

I'm just looking at this method for horizontal fence location work. The gathering of vertical data could be finessed, though. A helper with an HP can log those times when the elevation is not valid...he could also note times when a culvert, cross-fence, or driveway is passed, while the driver slows down for increased frequency.

There are a wide range of possibilities within a limited frame of usefulness. Zen and the art of surveying.

I'm working on a baseline right now for another test, just came in for a cool one. Its about 98 degrees out there.

Side subject.....

Where do you get a roof top mount ?? Or a 4 wheeler mount ?? Or are these items almost always homemade ??

Jimbo

I have never seen one for sale. Mine is my left arm, which gets really tired after awhile.

The nice thing about my arm is that it can lift the rover from the roof while passing over bumps and washboards. I think a roof mount should have some ability to absorb shock.

:>)

I think I might have an idea how to make one, but not with a shock absorber system. I might trust my left arm but not my crews'.

Jimbo

The Reliance unit has a magnetic mount flat plate with a quick connect extension that is threaded on the top for 5/8x11 (standard tripod/prism threads). You fix the plate to your roof, and then screw the Locus on the quick connect adapter. Then the adapter goes on the mag mount, and off you go. You probably have everything but the mag mount already in your kinematic Locus kit.....bob

Has anyone considered the fact that you dont want a semiconctor chip storing data to be in proximity to a strong magnet?

I know that if you wave a speaker magnet near a RAM chip, you are erasing, or at least corrupting data.

I want my mount, when my arm gets tired and I design one, to be of another design, one which is purely mechanical, or perhaps shielded from the magnetic field of the attachment. Thats not easy to do.

Excellllllllent point !
But it may be Ok anyway.

In my personal experience (somewhat small in this area) the effects of magnets on ram and even floppies is a bit overstated. These were of course accidental experiments (FU's) but no negative effects were noticed.

JImbo