Robotic TS as a low density laser scanner?Posted by Rapid Mapper on September 30, 2019 at 1:54 pm
We have a requirement to capture 50 points or so cross section points at every 10m interval inside of a 200m service tunnel. Thinking of acquiring a robotic TS to do this. Never used one before, so my question is, is there a tool that would allow a robot to function like a laser scanner?, i.e set it to automatically capture say at every 2 Deg. Vertical angle to capture our cross sections?
- 11 Replies
- MemberSeptember 30, 2019 at 4:15 pm
Not that I know of. Would be much cheaper to sub or rent a scanner. 200 meters would only be 10 setups for even a short-range. Could do the whole thing in under an hour.
- MemberSeptember 30, 2019 at 4:18 pm
I’d just use a reflectorless instrument and do the setups… It seems overkill to scan something like that..
- MemberSeptember 30, 2019 at 4:19 pm
Although now I see you’re in Malaysia – so I have no idea if there are business constraints I don’t know of…
For ~1000 locations you could walkthrough and put temporary markers at each 10m section location and just point a reflectorless laser dot?
Even if you pre-calculated and point to each location to turn to and observe you could go the shots in two days with a manual total station. Speaking from experience using one that doesn’t require tangent clamping (friction drive)
- MemberSeptember 30, 2019 at 7:23 pm
in the Leica world this application is called “Grid Scan”
- MemberSeptember 30, 2019 at 8:23 pm
Trimble robots can also do this – there is a scan function in Access that will let you input parameters as discussed:
If I remember correctly, you can define it by grid distance or by angle. It will ask you to take a reflectorless shot to define the average distance away from the station and compute the time and number of shots from that.
The problem with using a standard TS as a scanner is that, unlike dedicated scanners or the integrated units like the SX10 or MS50, these units typically wait for a return on each reflectorless beam before moving on to the next one. (At least, the last time I checked they did.) So if you have a very low angle of incidence, dark/wet surfaces, or difficult atmospheric conditions, the station may take forever to get the scans done. Eventually it will time out and move on, but you will get poor results and spend a lot of time to do it.
That being said, for a low cost, very-bare-bones scan under good conditions, they work just fine. I have used them to do building faces and hillside “scans” with excellent results.“…people will come to love their oppression, to adore the technologies that undo their capacities to think.” -Neil Postman
- MemberOctober 1, 2019 at 12:05 pm
Neither the Leica nor the Trimble routine will intelligently ascertain whether or not it is observing the shots directly on a section line at a station.
If it is needed to report observations at exact locations both would require heavy interpolation – which may be fine. Would need to know more about the deliverable that is needed.
- MemberOctober 1, 2019 at 2:54 pm
Good point – there is not a “cross-section” scan routine, at least on the Trimble units.
Dedicated scanner would be the way to go, then.
Depending on accuracy requirements, you could even use something like a GeoSLAM Zeb-Revo. Walk out and back for one session, about fifteen minutes at a 1mph pace. Download registered scans and pick cross-sections wherever you need to.“…people will come to love their oppression, to adore the technologies that undo their capacities to think.” -Neil Postman
- MemberOctober 1, 2019 at 6:10 pm
Depends on the product needed, might be worth it to just take reflectorless shots manually. Its only 20 sections, assuming 2 sections a set up that’s only 10 set-ups, not likely to buy a whole scanner and take on a whole learning curve to save that amount of work.
- MemberOctober 5, 2019 at 4:21 pm
I use a Trimble S7 that has light scanning ability’s that does let me scan and take pics but it is slow compared to a scanner. If you have the time to use this method than it should work for you but if you need the density and the speed of a scanner than definitely rent a scanner.
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