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Laser alternative to tape measures and calipers and verniers? - No not distance measurement

Laser alternative to tape measures and calipers and verniers? - No not distance measurement

Laser alternative to tape measures and calipers and verniers? - No not distance measurement

(OP)
Has anyone read of, used, or know of any laser hand-held measuring tools for benchmarking [a client's] water jet / laser cut piece parts, stampings, formed parts and fabricated subassemblies?

I am looking for a digital or laser [or other] hand-held technology to replace my mechanical rules and tape measures to travel to a facility, measure parts and fabricated subassemblies, and model them up back at work.

Thank you in advance for any guidance, suggestions or tool names you can share.

Chris in NC

RE: Laser alternative to tape measures and calipers and verniers? - No not distance measurement

Google "Faro"

Regards,

Mike

The problem with sloppy work is that the supply FAR EXCEEDS the demand

RE: Laser alternative to tape measures and calipers and verniers? - No not distance measurement

3D laser scanning can work, but it extremely expensive. Further, it creates "literal" 2d images in three-D that, once rotated, show exactly the images from only the original scanned direction. The final software - after MANY multiple images from the entire plant scanned area are "joined together with each other to a common reference point and axis" - need to be "sewn together" into a single very large file of approximate outside dimensions. And those dimensions are "outside of pipe" = NO centerlines nor work points nor distances. Only the outside of the flashing and insulation approximations.

So, what I do is complex, but works to 1/8 inch or so when you are on the floor, and the pipes are 45 to 90 feet up.

First, KNOE EXACTLY how accurate you need your numbers to be. Don't fool yourself, but don't pretend you can get 0.016 inch accuracy on a pipe location. Then again, when you cut a pipe, +/- 1/8 to +/- 1/4 inch is "less than the width of a welding rod" ...

And you can use this method for less than $200.00. Anywhere.

1. Go to your local Home Depot or Lowes. Get a TALL right-angle gage (I use a 4 ft gage used for marking 4x8 plywoods and a three-way level gage used for fence posts. Mount the 3-way level gage to the right angle gage so you can actually tell "what way is "up"" when you use the laser distance detector.

See, the biggest problem with those is that you CANNOT "look up at the pipe" while reading the laser while aligning the laser to a specific point while KNOWING absolutely that you are really are measuring some vertical point high overhead while telling when you are perpendicular to the floor/slab/gravel. While trying to hold the laser distance finder some exact distance from the floor/slab/gravel.

So you get very, very sloppy readings. Unless you are laying on the gravel trying to simultaneously click the laser distance while aiming the laser from the gravel at the bottom of the pipe!

In the photo's below, I'm simulating measuring the width, centerline, and heights-above-floor for a fan blade in the living room.

- Mount the 3-way level gage at a convenient height above the floor - I use 36 inches, since I can hold the square perpendicular in x while looking up at the pipe while holding it near-vertical in y. (A true 3-way level square on a tripod a fixed distance above the floor would be ideal, but then you are assuming your floor/slab is dead-level.)
- Set the laser range finder to "measure from the back of the range finder".
- Hold the laser range finder at the square on the 3-way level gage, then move the level gage and laser so you are aiming at the center of the pipe overhead. The square will keep you accurate to the floor, and you need to keep moving the assembly until the 3-way level gage is "near-zero" deviation and the laser pointer is where you want to measure overhead.
- Press the "measure button" when your laser is at the right point overhead.
-Have your helper (or yourself) mark the position on the floor where you measured! Use a marks-a-lot or crayon or Sharpie. DO NOT SKIP THIS STEP. After a few minutes, I will guarantee you will not be able to re-create the geometry.
- For pipes, look for the lowest point on the insulation, for a bare pipe at the low point, or for the "center" between two tangent points. The pipes will vary slowly with the cosine near the centerline, so you won't be too far off if you miss by a few millimeters or 1/86 inches left or right of CL.
- Near the same point where you took an elevation, take two tangent point measurements. Mark them on the floor or plywood panel you are using.
- Your CL elevation will be 1/2 (tangent distance) + bottom elevation above floor. Then try to figure out how high your floor is.

RE: Laser alternative to tape measures and calipers and verniers? - No not distance measurement

Typical laser scanners use parallax and can directly measure displacement of the scanned surface. This is how the Kinect technology that Microsoft bought works - a laser is used to generate a consistent projected pattern of dots which a camera detects; the difference between the detected pattern and the ideal pattern is used to calculate the depth from the projector.

Some less expensive systems use laser line projection, such as seen at David's Laser.

You might also look at photogrammetry - it depends on how precise you need the results to be. It's how they map actors into scenes in movies.

RE: Laser alternative to tape measures and calipers and verniers? - No not distance measurement

The first question I have is why do you need to reverse engineer parts that are produced using water jet or laser cutting? All water jet and laser cutting machines are CNC, so there must be a digital model somewhere that was used to produce the CNC program. If you want to verify (or benchmark) the geometry of a water jet or laser cut part against a digital model, you can do this using a portable CMM or laser scanner. Each has advantages/disadvantages. The portable CMM arm is probably cheaper, but is limited in the size of part it can inspect. The handheld 3D laser scanner is likely much more expensive, but can handle larger parts and is much quicker to use.

Most importantly, it is not a simple task to create a good quality digital model from the database of points you will get from the CMM arm or the laser scanner. The laser scanner will output a point cloud, and these points will not represent perfect surfaces/boundaries. The database of points output from the CMM arm or laser scanner are typically overlaid/fitted to an existing digital model and checked for deviation from a control model's surfaces. If you need to produce a digital model from the point cloud, it requires a huge amount of manual clean-up work to sort thru all of the points and create a clean, usable 3D digital model. There are some software applications that can perform this task fairly well, but they are not cheap.

RE: Laser alternative to tape measures and calipers and verniers? - No not distance measurement

Someone must have these scanners down to a pretty simple implementation. I had new knee braces made a couple of years ago and they put a reflective dot on my knee and just scanned up & down with a hand held scanner. It "painted" a 3D image on the monitor, when there were no more gaps the technician stopped scanning. The whole process was quite quick & the technician did not appear to have any special training. The software seemed to be very simple. I'm sure there was some data cleanup involved and perhaps these things don't have to be highly precise. A couple of weeks later the custom made carbon fiber braces with titanium hinges showed up. They fit much better than the one made 20 years ago. The old one was based on many many individual measurements made with tape measures and permanent markers putting all sorts of little dots and x's on my knee. That measurement took over an hour and the result was not so great.

----------------------------------------

The Help for this program was created in Windows Help format, which depends on a feature that isn't included in this version of Windows.

RE: Laser alternative to tape measures and calipers and verniers? - No not distance measurement

Plenty of "lower" cost 3d scanners out there..
resolution/accuracy will vary..
https://www.fuel-3d.com
http://cubify.com/Products/SenseOrder?gdftrk=gdfV2...

my question would be the same as tbuelna though.. Why can't they simply share the CAD files (step file or similar neutral format)? No traveling/scanning/remodeling needed
If this was a QC/Inspection requirement then obviously thats not whats needed but the OP seemed to indicate he just takes measurements so he can remodel back at his shop..

RE: Laser alternative to tape measures and calipers and verniers? - No not distance measurement

I got the impression that there were no "previous CAD models" at all, and the original poster needed to get accurate as-built, as-installed, as-now dimensions of the piping now in his plant to design and fabricate NEW pipes intersecting or replacing pipes already built long time ago.

I owe still pictures of the laser height-finding and distance-finding jury-rigs I've used for measurements. Haven't done them yet.

What's the best way to upload 6-12 photo's, without separately putting each up as separate reply and a separate image? One powerpoint-type group?

RE: Laser alternative to tape measures and calipers and verniers? - No not distance measurement

A previous company, sadly, did have to reverse engineer their own PC boards, because management was so stupid that they felt it was OK to delete design files to make room the server without doing even a hint of backup. Needless to say, the reverse engineering did not go off smoothly, as at least two boards had to be reverse engineered a second time to fix the errors from the first time.

TTFN
I can do absolutely anything. I'm an expert!
homework forum: //www.engineering.com/AskForum/aff/32.aspx
FAQ731-376: Eng-Tips.com Forum Policies forum1529: Translation Assistance for Engineers

RE: Laser alternative to tape measures and calipers and verniers? - No not distance measurement

(OP)
Many of you have asked about existing documentation. There is very little. this is another case of a small entrepreneur who developed a good line products and never actually documented in detail what he is making: everything with vendors was done with verbal discussion and a handshake. Patterns are laid out for fabricators and assemblers; but no formal documentation as you guys know it (ergo - there ARE no drawings). I did similar work for another small company out west: No formal documentation to protect the owner. This is more common than you may like to believe. Then the companies' products boom, sales jack up and there's a panic because there's no way to get competitive piece part bids; no way to guarantee finish quality, welds, design intent etc. etc. etc.

Welcome to my world.

RE: Laser alternative to tape measures and calipers and verniers? - No not distance measurement

God supposedly treats idiots differently that asses, since asses know that they are doing wrong, but do so anyway; that's my ex-company. Idiots just don't have the clarity of thought to realize that they're doing stoopid things.

TTFN
I can do absolutely anything. I'm an expert!
homework forum: //www.engineering.com/AskForum/aff/32.aspx
FAQ731-376: Eng-Tips.com Forum Policies forum1529: Translation Assistance for Engineers

RE: Laser alternative to tape measures and calipers and verniers? - No not distance measurement

(OP)
MCGYVR! THANK YOU! That's very close to what I'm looking for. SCANIFY and SENSE 3d - both look to wrk wonders. Plenty of Youtube videos on these technologies too.

RE: Laser alternative to tape measures and calipers and verniers? - No not distance measurement

You need to pay attention to the accuracy produced by those low cost optical scanners. The technical specs for the SENSE 3d scanner list an X/Y resolution of just 0.9mm at a scanning distance of 0.5m, which is probably not suitable for reverse engineering the type of components described.

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