1mm accuracy

Please post any tips or advice you have in general relating to laser scanning either whilst onsite or office based.
User avatar
V.I.P Member
V.I.P Member
Posts: 247
Joined: Wed Aug 21, 2013 8:01 pm
Full Name: Sung Joon Ahn
Company Details: CurvSurf
Company Position Title: CEO_CTO
Country: Republic of Korea
Linkedin Profile: Yes
Location: Seongnam-si, Korea
Has thanked: 3 times
Been thanked: 16 times

Re: 1mm accuracy

Post by Joon »

With coordinate metrology, the relative accuracy to the range of measurement is more practical than the nominal one. E.g., a measurement accuracy of 1 nm is too low for 10 nm pattern of semiconductor circuit. In contrast, a measurement accuracy of 1 mm is too high for 1 km long bridge.

The range of relative measurement accuracy for industrial applications:
1. The lower bound: 1/100, i.e. 1 cm for 1 m
2. Usual requirement: 1/1,000 ~ 1/100,000
2. The upper bound: 1/1,000,000, i.e. 1 mm for 1 km.

There are a variety of measurement methods and tools available for industrial applications.

For moon observation, a telescope.
For cell investigation, a microscope.

User avatar
Dave Andrews
V.I.P Member
V.I.P Member
Posts: 140
Joined: Thu Oct 18, 2012 8:58 pm
Full Name: Dave Andrews
Company Details: R.E. Warner Associates Inc.
Company Position Title: 3d Scanning Coordinator
Country: USA
Linkedin Profile: Yes
Location: Canton, Ohio
Has thanked: 2 times
Been thanked: 8 times

Re: 1mm accuracy

Post by Dave Andrews »

landmeterbeuckx wrote: Sat Mar 07, 2020 5:07 am
Dave Andrews wrote: Fri Mar 06, 2020 5:51 pm
landmeterbeuckx wrote: Fri Mar 06, 2020 3:05 pm

What price range are these trackers actually? I knwo Leica and Faro have them but have never used or seen one irl.
We have a little over $140k in 1 tracker and everything to do what we need. Now, we also do high precision alignment so the tooling needs a huge expense.
wow, you got to have some decent jobs for this gear to earn it back. I suppose the rates aren't as conventional surveying?
Haha yeah it’s a touch pricey. Our tracker rate is 4 times the survey rate.
"The harder you work, the harder it is to surrender."
Woody Hayes
User avatar
Global Moderator
Global Moderator
Posts: 1828
Joined: Sun Aug 12, 2007 9:22 pm
Full Name: Steven Ramsey
Company Details: 4DMax
Company Position Title: Technical Specialist Scanning
Country: UK
Skype Name: steven.ramsey
Linkedin Profile: Yes
Location: London
Has thanked: 27 times
Been thanked: 39 times

Re: 1mm accuracy

Post by stevenramsey »

Usual question has anyone bothered asking the client what they are using the data for and helping them understand what level of Accuracy/precision they really actually need
Steven Ramsey

Home [email protected]
Work [email protected]
Mobile +44 7766 310 915
V.I.P Member
V.I.P Member
Posts: 504
Joined: Mon Aug 11, 2008 4:13 pm
Full Name: James Rye
Company Details: Merrett Survey Partnership
Company Position Title: Spatial Analyst
Has thanked: 1 time
Been thanked: 15 times

Re: 1mm accuracy

Post by Jamesrye »

Yes, we've asked the client - they are looking at a subsidence issue. The trouble is that when a client reads something like the article below, why wouldn't they want the best possible accuracy?
https://www.spar3d.com/news/lidar/faro- ... -accuracy/

We get over-specced tenders all the time! Clients asking for 2mm point spacing on a building facade and then when you deliver, they cannot work with the point cloud and so we have to reduce it.
User avatar
Global Moderator
Global Moderator
Posts: 1628
Joined: Sun Mar 04, 2012 5:43 pm
Full Name: Jonathan Coco
Company Details: Forte and Tablada
Company Position Title: somniator
Country: USA
Linkedin Profile: No
Has thanked: 49 times
Been thanked: 121 times

Re: 1mm accuracy

Post by jcoco3 »

That's a shame :| I wish you luck in educating your client...if you can.

There is a saying that I have heard that is a good representation of this ignorance problem.

"Measure it with a micrometer, mark it with caulk, cut it with a chainsaw."

How is the contractor going to ensure they hit that mark even if you can? This is why I also suggested supplying tracker services during construction.

Edit: Sounds like the project is still over-specified, but at least you might get a chance to use a tracker, and possibly charge 4x what you would normally due to their ignorance. I think that it would be better to educate them and get the specified accuracy reduced, but in the event that fails you will still be giving them excellent data.
V.I.P Member
V.I.P Member
Posts: 974
Joined: Tue Mar 29, 2011 7:39 pm
Full Name: Scott Page
Company Details: Scott Page Design- Architectural service
Company Position Title: Owner
Country: USA
Linkedin Profile: No
Location: Berkeley, CA USA
Has thanked: 107 times
Been thanked: 48 times

Re: 1mm accuracy

Post by Scott »

jcoco3 wrote: Mon Mar 09, 2020 1:25 pm "Measure it with a micrometer, mark it with caulk, cut it with a chainsaw."
That tat would give the surgeon a laugh, too :D
Post Reply

Return to “Tips & Advice”