Industrial Scans - Certified to 0.02'

Posted by: James Fleming

[Rant on]

Nothing bothers me more than cr@p like 0.02' tolerances.?ÿ That's like saying all the measurements have to within "blue".

The first thing anyone learns in any college class that involves measurements in the physical sciences is that all measurements have error, therefore a measurement (or a measurement tolerance) consists of three parts - the number, the precision range, and the repeatability.?ÿ If an objects?ÿ"true" value is 1000, then a measurement of 950 +/- 60?ÿ is "correct" and a measurement of 990 +/-2 is "incorrect".?ÿ

[Rant off]

Just certify that 66% of the measurements are within 0.02 +/- .05; now you've got a tenth to play with?ÿ?ÿ ??ÿ

If I could add to the rant. When surveyors perpetuate this nonsense.?ÿ Many times by contracting a job that they could never meet those tolerances with existing staff and equipment.?ÿ Airports and structural steel high rise?ÿ jobs come to mind. My 2 cents, Jp?ÿ

I've got a little more breathing room. 0.08; one inch.?ÿ

Looking for suggestions for control points, preferable ones on the ground. I could use overhead aerial but that will be hard with bar code level loops...

Anyone know how well those 10 dollar Trimble stickers hold up to traffic? I've got 30 foot of DOT tape.?ÿ

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