PocketTopo experiences?

Techniques, equipment and issues. Also visit the NSS Survey & Cartography Section.

Moderator: Moderators

PocketTopo experiences?

Postby Dan Henry » Jan 15, 2010 2:41 am

Hi all,

Delving into trying to sketch with PocketTopo some, and was looking for any experience or advice about this thing that might not be obvious. Anything useful or interesting, or cautionary would be great. Have run into a few weird :shrug: :shrug: :shrug: things about it, and was wondering if anyone else had.

Thanks,

Dan
User avatar
Dan Henry
Frequent Poster
 
Posts: 54
Joined: Feb 13, 2008 4:48 pm
Name: Dan Henry
NSS #: 47794
Primary Grotto Affiliation: Flittermouse Grotto
  

Re: PocketTopo experiences?

Postby Crockett » Jan 15, 2010 3:53 pm

Be prepared to get religion Dan. The members of my survey team are constantly asking: "Are you saved?".

It works great. Even I can sketch reasonably with it. On a recent geology trip we were taking a lot of quick shots with no backsights to get an apparent dip. The Compaq iPAQ 211 pda locked up with about 8 shots not saved. Fortunately it was on the data screen and I was able to call them off to be written down and reentered later...after pushing reset. It saves to nonvolatile memory which is relatively safe and retrievable barring physical damage to the PDA...but you gotta be saved.

The focus of "paperless cave survey" has been on the instruments and wireless transfer. The paper always been in the hands of the sketcher. You can use regular instruments with PocketTopo and be paperless.

A couple of issues and problems that have work arounds: The station designation system allows only numbers. The profile is completely unwound to the point of being almost useless sometimes. The text file output is messy. The Therion file output doesn't seem to actually work with Therion. There is a way to include backshots that should be easy but I haven't figured it out just yet so I put those in the comments. The desktop PC installation doesn't seem to work the same way as the PDA install even considering pen input versus mouse input. You can't select a group of lines, like a cross section, and move it to make way for more cave so I tend to draw them further off to the side than necessary and that makes it hard to compare the dimension of the different views (probably better to draw the cross sections in the profile view or improve my technique).

I am sure there are reasonable solutions to these problems or just features and techniques that I have not learned about.

I attach the PDA inside a small waterproof box and open it when needed. I have not dropped a stylus yet. I must confess I find the stylus in my mouth sometimes, it should probably be on a string. Battery power is not an issue with the extended battery for a iPAQ 211. The last survey was really muddy and there was only one problem. The stylus hole got so much mud pushed down in it that the stylus would not go back in. Later I used a wipe and the stylus to clean out the hole.

I too would be interested in experiences and work arounds. An extended symbol set using the different color pens might be useful but if Mr. Heeb added different brushes or a way to import brushes, now that would be useful.

...and maybe an autosave feature.
Crockett
NSS Hall Of Fame Poster
 
Posts: 243
Joined: Feb 5, 2006 7:10 pm
Location: Pineville, Kentucky
Name: Mike Crockett
NSS #: 33730
Primary Grotto Affiliation: East Tennessee Grotto
  

Re: PocketTopo experiences?

Postby Dan Henry » Jan 15, 2010 8:02 pm

Mike, I'm Glad to hear it's working well for you. It seems awfully attractive for cutting all the time you spend plotting angles and scaling lruds on plans, profiles and cross-sections, especially if you take the lruds with the distox, as it plots them automatically.

The hang ups I have are about when to use "new" versus " new cave". I want to keep my data all together in a single "cave" file, but to keep your sketching working good, you need to change files on certain occasions, like when you start a side passage and you've already sketched in a section, as If you don't switch files, your profile plot will overlap the one you've already drawn, starting at the tie station for the side passage. Another case is when you're sketching a complicated area and find that there's a passage that trends under one you've already drawn, and you need to break it out away from the upper level to keep things from getting incomprehensible. My concern is that the program behaves unpredictably when you start a new survey in an existing "cave" file. Sometimes the existing profile lineplot comes in, sometimes not; sometimes the program doubles the data in the list, duplicating all the existing data, but not consistently. One thing I tried was to save a blank file at the start of each new "cave" file. Then start surveying after selecting "new", starting a new file, but in the existing "cave", even though the first file was blank. This seemed to help with the profile display problem.

Another weirdness I've noticed is the export files. The text file format seems like it will work fine in WALLS with a bit of text editing. Walls will take a shot with no "TO" station and put it in as a splay, so these splays *are* the LRUDs, so you don't have to fool with them unless you have a special case. Also, the DXF file export for the plan and profile view screens does indeed make a CAD readable file that is layered somewhat well. One weird thing here was the units in the DXF file weren't the feet they were surveyed in, but they weren't meters either. They ended up being doubled meters, so that in order to get the DXF file to be in the actual surveyed units, I had to scale down by half, then convert from meters to feet (x3.280833333 (though that is the US survey foot...)).


On the backsights and frequent saving, I was planning on having that be part of the workflow, being more or less:

Move to new station.
Shoot Backsight & verify
Shoot LRUDs
Shoot Forward station
Save
Sketch in shot you just verified: PLan, Profile, X-section.
Save
Repeat until crispy

Wondering how hard it will be to fix bad shots once they've been plotted in and drawn to, so was hoping to verify the backsight before starting to sketch that shot. Clearly this is not sophisticated enough to alter your sketch if you find out the FS/BS don't match and have to make a change.

Some of the reports and literature on this system suggest the sketcher should keep the DistoX with them, so they know exactly where the shots were taken and which splays are which without having to have a running conversation with a seperate instrument person. I think this may seem unfair to people who are used to doing it the way we do now, as there will basically be a sketcher/instrument person and a front point and back point person, if backsights are being taken, which is...always.

I'm curious to hear what our European counterparts who use this system have to say about any of the apparent bugs and workarounds.

Thanks!

Dan
Dan Henry
Asheville, NC
NSS#47794
User avatar
Dan Henry
Frequent Poster
 
Posts: 54
Joined: Feb 13, 2008 4:48 pm
Name: Dan Henry
NSS #: 47794
Primary Grotto Affiliation: Flittermouse Grotto
  

Re: PocketTopo experiences?

Postby Martin Sluka » Jan 17, 2010 7:13 am

First of all - Beat made the PocketTopo for himself, so use it as is, let it be or make your own, better.

The logic of PocketTopo strictly follows the Toporobot logic. The roots of Toporobot are in beginning of seventies. Don't be surprised the logic of program is a bit strange compared to more recent ones.
The link on page of Toporobot: http://www.geo.unizh.ch/~heller/toporobot/, but it looks the ftp links don't work.
But documentation is available, most important is chapter about "Toporobot Method": http://www.geo.unizh.ch/~heller/toporobot/English/Manual/ToporobotMethod.html (German) or http://www.geo.unizh.ch/~heller/toporobot/Francais/Manuel/MethodeToporobot.html (French). Check [url]translate.google.com[/url]

The more actual is Windows compatible version is software GHTopo using the TopoRobot method too: http://siliconcavings.chez-alice.fr/

The cave survey is divided to "series". Each series has its own number beginning 1, 2,m... Each series start with 0 and continue 1,2,3, .... It mean, first station of first series has number 1.0 and so on. The series MUST NOT cross itself. In PocketTopo you may divide surveying in similar way to start with new file for each series saved in one directory in root directory (PocketTopo doesn't recognize subdirectories). If you open an file you may add surveys to it and you'll see another filess as lines only.

How to exploit the PocketTopo features: Make an new directory named after cave. Open PocketTopo, start with new cave, switch on DistoX and wait all saved fake measurements are transfered to PockedTopo. Start with new cave again, it will erase all faked measurements. Save the file to your directory.
Surveying: doesn't matter which method of surveying you use start with surveying of cross-section. Drag the cross-section from station and draw it. Survey another splay shots on walls of passage and draw map and elevation. Dont't survey too many splay shots, only 4-5 and draw particular part of passage. Repeat. Survey more splay shots for important objects inside passage and draw them. You may add a note on end of line of shot - "pit" or .... Survey three times the shot to next station. An so on.

Therion: Last developer version is able to import data from PocketTopo Therion export file. In data editor open new file and Import surveying data from "PocketTopo Therion export file". In map editor make new file, save it and import background picture from "PocketTopo Therion export file". For surveying data you may change the dash to dot for objects inside passage. Dash is for points on walls. It will be used in future for 3D models.

Martin
User avatar
Martin Sluka
NSS Hall Of Fame Poster
 
Posts: 383
Joined: Mar 17, 2006 11:28 am
Location: Prague, Czech Republic
Name: Martin Sluka
NSS #: 29010
  

Re: PocketTopo experiences?

Postby Dan Henry » Jan 18, 2010 1:29 am

Martin,

Thanks for your post. I did check out those links you posted, and between Beat Heeb's documentation for PocketTopo, what you wrote in your post, and the documents on the toporobot method, I think some of the items I had been worried about have been cleared up.

Your point about taking just the cross section shots and drawing the cross section before taking any further splay shots was just the sort of thing I was looking for.

On taking backsights, I know the program lets you take 3 readings to set a new station and averages them(?) , but if a magnetic anomoly were to exist where those reading were taken, it would affect all of those 3 readings, and you might not catch it without a backsight. I have been taking a single shot backsight to catch just this sort of scenario, manually verifying agreemement within tolerance, and commenting the shot as a backsight. It seems this is about the best way to do it unless somebody has another better way? I had read on a UK forum where someone was saying to take 3 backsight readings also, but that would mean you would be constantly manually renumbering stations, which defeats the streamlining the program allows.

Mike,

Are you sending the DXF files to your project cartographer, and is he fine with getting those instead of paper sketches?

Thanks!


Dan
Dan Henry
Asheville, NC
NSS#47794
User avatar
Dan Henry
Frequent Poster
 
Posts: 54
Joined: Feb 13, 2008 4:48 pm
Name: Dan Henry
NSS #: 47794
Primary Grotto Affiliation: Flittermouse Grotto
  

Re: PocketTopo experiences?

Postby Footleg » Jan 18, 2010 5:01 am

I have been using PocketTopo with a DistoX since last year and have been very happy with this system. I protect my PDA with an Aquapac PDA case which makes it completely waterproof. See http://www.aquapac.net/usstore/waterproof-pda-ebook-kindle-cases-598-0.html. I can sketch through the case, and if it all gets muddy then I just wash it off in a stream underground. I use a plastic PDA stylus (from ebay) rather than the one that came with my PDA. These are mud proof. I carry a spare too.

I've not had any crashes so far (using a Dell Axim 51v PDA). But the PocketTopo documentation says that is saves temporary recovery files constantly, including a copy to a memory card if fitting in the PDA. So you should not lose any data in the event of a crash. I think these files are deleted when you save your data, so you don't generally spot them. But if it crashes then it should be possible to recover all entered data after a reset. Best test this when playing above ground by resetting the PDA without saving to have complete confidence in it. I do of course save every now and then while surveying, but do not get too paranoid about it.

I have generally started a new file per trip. All the files in a single folder are treated as the same cave, but only one file is active at a time. This effectively makes all the data in the other files 'read only' so you cannot accidentally edit old data from previous trips while adding new data to an existing cave.

I export as TXT and run the converter I wrote to get the data into Survex (the application I use to manage my data). You can get that here: http://www.darkgem.com/wscc/caving-talk/index.php?title=CaveSurveyDataConverter

I bought a larger battery for my PDA (see ebay) which runs it constantly for 24 hours. So that is not a problem either.
User avatar
Footleg
Frequent Poster
 
Posts: 65
Joined: May 15, 2009 8:03 am
  

Re: PocketTopo experiences?

Postby Martin Sluka » Jan 18, 2010 7:07 am

Footleg wrote:I I use a plastic PDA stylus (from ebay) rather than the one that came with my PDA. These are mud proof. I carry a spare too.


May you write reason you don't use a stylus chained to outside of AquaPack?

m.
User avatar
Martin Sluka
NSS Hall Of Fame Poster
 
Posts: 383
Joined: Mar 17, 2006 11:28 am
Location: Prague, Czech Republic
Name: Martin Sluka
NSS #: 29010
  

Re: PocketTopo experiences?

Postby Footleg » Jan 18, 2010 10:07 am

sluka wrote:
Footleg wrote:I I use a plastic PDA stylus (from ebay) rather than the one that came with my PDA. These are mud proof. I carry a spare too.


May you write reason you don't use a stylus chained to outside of AquaPack?

m.


Only because I have not got around to tying one on yet! But you are right, this is what I should do!
User avatar
Footleg
Frequent Poster
 
Posts: 65
Joined: May 15, 2009 8:03 am
  

Re: PocketTopo experiences?

Postby Crockett » Jan 18, 2010 2:02 pm

I used the shotgun approach for the cartographer and sent the txt file, dxf of both plan and profile, then I put all three into a pdf and sent that too. Gulden probably used the dxf files. In a few hours he sent a pdf with the survey added to a more complex map segment drawn in AutoCAD.

The Dell PDA looks like a less expensive alternative device with screen size similar to the HP iPAQ 211 but I just bought another one new on eBay for $271. Now I have a surplus.

When Auriga features sketching I will pay $50 for Styletap and try it on these Windows Mobile devices rather than purchasing a Palm. Until then PocketTopo with sketching maintains a significant advantage although the data entry and handling of Auriga is better. Any word Luc?
Crockett
NSS Hall Of Fame Poster
 
Posts: 243
Joined: Feb 5, 2006 7:10 pm
Location: Pineville, Kentucky
Name: Mike Crockett
NSS #: 33730
Primary Grotto Affiliation: East Tennessee Grotto
  

Re: PocketTopo experiences?

Postby Dan Henry » Jan 18, 2010 4:46 pm

I tested the autosaving file scenario. I took 5 shots and saved, then took 5 more shots, waited for them to appear on the screen, then a minute longer to allow the program to do whatever aoutosaving it might do, then yanked the battery without saving, simulating a hardware crash. After re-starting the device, the file had... only the first 5 shots. So I guess I will get saved, like Mike suggests.

Mike, I got a Dell Axim X51 for $99 refurbed, then a 3600mah battery, all of this in a otterbox 2600 pda case with the touchscreen window. The extended battery would not fit with the back plate on, so I left it off and fooled the battery cover sensor into thinking it is covered by cannibalizing the old cover plate from the old 2200mah battery the PDA came with. I don't like sketching with the stylus, so i took some 0.5mm plastic tip mechanical pencils, took the lead out, and marked them near the tip with a sharpie so I could tell them apart from regular pencils loaded with lead, and those work great and feel better in your hand, at least in my opinion.

I found the DistoX slips right inside a nalgene bottle, but a 32 oz. one is way too big. So, looking around for a 16oz nalgene with a regular sized top opening, found the nalgene sippy cup was perfect, just replace the sippy top with a regular nalgene top and put a bit of foam in the bottom (about 5mm or so thick) to fill the extra length. A lot lighter than a pelican 1030 and protects the Distox from scratching the lens or getting crushed in your pack, at least in transit. http://www.nalgene-outdoor.com/store/SearchResult.aspx?CategoryID=40 See image below.

Also, worried about about the PDA screen getting damaged in transit through the PDA window in the otterbox case, so fashioned a plastic hard cover for the window, which I fasten on with a few bits of bicycle innertube, then take off for surveying.

Anybody have any other ideas on the backsights?

Thanks!

Dan
Image
Dan Henry
Asheville, NC
NSS#47794
User avatar
Dan Henry
Frequent Poster
 
Posts: 54
Joined: Feb 13, 2008 4:48 pm
Name: Dan Henry
NSS #: 47794
Primary Grotto Affiliation: Flittermouse Grotto
  

Re: PocketTopo experiences?

Postby lleblanc » Jan 19, 2010 11:07 pm

When Auriga features sketching I will pay $50 for Styletap and try it on these Windows Mobile devices rather than purchasing a Palm. Until then PocketTopo with sketching maintains a significant advantage although the data entry and handling of Auriga is better. Any word Luc?


While I don't intend to value the respective merits of these PDA apps, I suspect they were developed with different goals, perhaps because they were introduced at different moments of the recent history of underground electronics in cave surveying.

In 2003, when I first released Auriga, underground PDA use was non-existent. While my initial goal was only to write a field-use coordinates calculator. It later evolved into providing a smart graphical rendition and data handling tool while underground or in the field. Since our expeditions involve several teams, many new caves, frequent connections and GPS use, I concentrated on input validation, loop handling (detection, report, display and closure) and data handling (search, merge and exchange) as well as GPS tracking. To us, these features were probably more needed than giving up paper. PocketTopo appeared in 2008, when cavers were more keen to use a PDA in caves, and its companion DistoX made splay shots very quick and convenient for sketching, so it's likely the focus was put more on sketching, and I think Beat did a good job at it. Now that I pretty much exhausted the other priorities I had, I plan to implement on-screen sketching into Auriga in 2010. Some tell me they'll never use it as they prefer paper, for its feel and better precision, but time will tell whether that picks up.

Regarding series, I agree with Martin Sluka that they're a great concept for managing passages. Unfortunately, being unsupported in most (if not all?) software except Toporobot, cavers instead hack the session concept (aka "surveys" in Compass) for this purpose, even though these were meant to manage teams, instruments and methods, not cave passages. Like assuming a passage is always mapped by a single team using the same instruments and methods.

Auriga can recognize series and handle them as passages (to transmit, color, show/hide, count/exclude them in map, stats, etc.) However, supporting series does not require to implement the "Toporobot rules". When I first worked on Martin Melzer's original Auriga code (43K!), I didn't even know these rules existed. I quickly replaced the numeric station names by alphanumeric ones to suit our naming scheme. Still, some caves imported into Auriga remained incomputable due to our disregard of these unknown rules (non-consecutive station names, no series beginnings, passages mapped from the end connecting to others mapped from the entrance, etc.) Eventually, I rewrote the computation algorithm to do away with any constraint on the way the survey data was assembled. Any cave with unique 12-character (or less) station names can now be computed by Auriga, with or without series, including caves with dive data, probably the most complicated case.

Regards,


--
Luc Le Blanc
http://www.speleo.qc.ca/Auriga
User avatar
lleblanc
Frequent Poster
 
Posts: 87
Joined: Aug 10, 2007 2:19 pm
Name: Luc Le Blanc
  

Re: PocketTopo experiences?

Postby Crockett » Jan 19, 2010 11:44 pm

Auriga wrote:Now that I pretty much exhausted the other priorities I had, I plan to implement on-screen sketching into Auriga in 2010.


That is great news. I will be an early adopter.

I am just a hack sketcher but Dan Henry produces masterpieces with paper and pencil. If Dan employs a paperless system many other proficient sketchers will be compelled to try it, then their objections will likely be overcome by their experiences.

Nice Distox mod there Dan and it can be an empty bottle in case of emergency.
Crockett
NSS Hall Of Fame Poster
 
Posts: 243
Joined: Feb 5, 2006 7:10 pm
Location: Pineville, Kentucky
Name: Mike Crockett
NSS #: 33730
Primary Grotto Affiliation: East Tennessee Grotto
  

Re: PocketTopo experiences?

Postby Dan Henry » Jan 20, 2010 8:36 pm

Thanks for the compliement, Mike, but I doubt my experiences with PDA sketching will influence anybody but me.

I did some more testing with WALLS, and found that it was capable of handling the toporobot style data (series.station), but with the added built-in WALLS behaviour of being able to assign a book number or trip prefix, with the benefits that provides. PocketTopo will be used as a data collection tool for the WALLS/Illustrator roundrtipping workflow. I will make PDF's of the data files and map in progress from Illustrator, load them back up on the PDA to view on Acrobat Reader and have the whole enchilada, short of doing an ICDS with a tablet , which I've read about, but makes me cringe, having shattered a tablet touchscreen before (though not a super ruggedized one).

Regards,

Dan
Dan Henry
Asheville, NC
NSS#47794
User avatar
Dan Henry
Frequent Poster
 
Posts: 54
Joined: Feb 13, 2008 4:48 pm
Name: Dan Henry
NSS #: 47794
Primary Grotto Affiliation: Flittermouse Grotto
  

Re: PocketTopo experiences?

Postby Scott McCrea » Jan 20, 2010 8:42 pm

Dan, just for kicks, put a piece of clear packing tape over the sensor and laser end of the DistoX. It would provide a lot of protection. It works just fine on my Bosch laser, but who knows with the Disto.
Scott McCrea
SWAYGO
User avatar
Scott McCrea
Global Moderator
 
Posts: 3198
Joined: Sep 5, 2005 3:07 pm
Location: Asheville, NC USA
NSS #: 40839RL
Primary Grotto Affiliation: Flittermouse Grotto
  

Re: PocketTopo experiences?

Postby Dan Henry » Jan 22, 2010 8:45 pm

I am going to do that, Scott. Won't stop serious damage, but will keep the mud off the optics.

Dan
Dan Henry
Asheville, NC
NSS#47794
User avatar
Dan Henry
Frequent Poster
 
Posts: 54
Joined: Feb 13, 2008 4:48 pm
Name: Dan Henry
NSS #: 47794
Primary Grotto Affiliation: Flittermouse Grotto
  

Next

Return to Survey and Cartography Forum

Who is online

Users browsing this forum: No registered users