Improved Laser Scanner setup and First Scan

[khalid]

Hi my fellows,
Came back after long long time.... i just posting here about my Laser scanner improved hardware..
As you are well aware, i have some funky old hardware for the David Laser Scanner... I did many scan with good accuracies but the scanning setup was heavy and mobility was an issue... So i did work on following points to improve the setup:
1- It can easily perform the scanning without calibration panel.
2- It can be easily disassembled and assembled in new location.
3-Compact in size for transportation
4- Aesthetically look beautiful
5- Electronics have all the control features
6- The complete setup is light weight.
7- Accurate and reliable

After, considering all above and lot more i was able to DIY the hardware and made the first test scan.. Attached you can see the scan of spray bottle .. Total 9 scans , each scan cycle took 2minutes.. Approximate height of the spray bottle is 250mm and 80mm in diameter...The alignment and stitching was a difficult part due to symmetry in the model.. However, i learn a lot in stitching the scans...

[dana_swift]

That looks very good, and handy to be portable!

What software do you use to stitch together the scans?

D

[khalid]

Hi Dana Thanks.. David Laser Scanner has a Utility 'ShapeFusion' in which i have stitched all the Scans
Regards

[myxpykalix]

Hey I see "McGruber" is back! Hey Khalid what else are you working on these days?

[khalid]

Hi Jack,
Doing nothing but scanning .. Attach is the picture of the table.. see the beautifully carved legs..these legs can be done on CNC.. If somebody here interested in CNC machining of the leg..i can scan the thing... just a nominal price less than a price of laser...

[Mayo]

Khalid I'm glad to see you're getting things working better with the laser scanner. It looks like you're now controlling the laser with a stepper rather than sweeping it by hand?

I'm wondering...
Are you able to change the resolution of the scan?
How do you determine what resolution of scan is sufficient for a given size object, using certain size bits for roughing and finishing?

At some point does a higher resolution scan just create an unnecessarily large file - with too much detail that the bit cannot define?

Or is it best to provide as much detail as possible in the laser scan, and then let the cam program eliminate the excess information based on the cutting bit sizes?

I admire you for having the brains and patience to work out all this electro mechanical stuff. I get totally confused by a lot of it so I'd be the kind of guy who would buy a ready made kit rather than the kind of guy (like you) that has the smarts to know how to make the kit.

I'll keep watching with great interest!

[khalid]

Khalid I'm glad to see you're getting things working better with the laser scanner. It looks like you're now controlling the laser with a stepper rather than sweeping it by hand?

I always controlled my Laser scanner with Stepper...But current setup has small gearbox and perfectly machined laser scanner hardware.. Its robust and rigid

I'm wondering...
Are you able to change the resolution of the scan?

Yes, I can change the resolution of scans upto 1600 x 1200 of the webcam. My above scan is the result of 800 x 600 resolution of CAM.. I use high resolution for the objects that have very fine details etc.

How do you determine what resolution of scan is sufficient for a given size object, using certain size bits for roughing and finishing?

At some point does a higher resolution scan just create an unnecessarily large file - with too much detail that the bit cannot define?

Or is it best to provide as much detail as possible in the laser scan, and then let the cam program eliminate the excess information based on the cutting bit sizes?

My technique is to get the part scan with its full details i.e upto 0.08mm...
Then i let the CAM decide its toolpath for specific tool...
The higher the resolution the bigger the File.. You have to make compromise.. For example my strategy is:
1- Scan the low detail portions with less-resolution
2- Scan the high detail portions with high resolution mode
3- Bring and align all the scan in software
4- Decimate the scan to loww poly

I admire you for having the brains and patience to work out all this electro mechanical stuff. I get totally confused by a lot of it so I'd be the kind of guy who would buy a ready made kit rather than the kind of guy (like you) that has the smarts to know how to make the kit.

I'll keep watching with great interest!

It took me almost two years to reach at this position... However, the too much time was due to scarcity in budgeted amount, less availablity of resources.. The most difficult was to get the Laser and Mr Richard Boucherd helped me gifting the laser.

[khalid]

i have a metallic horse with fine carving details... To test and improve my laser scanning setup i put this horse into practice: Following were the goals of this case study:
1- To determine How minute details i can get on such shiny metallic objects
2- To adjust parameters Hardware as well as software to achieve my goal
3- To do a Planeless scan and merge


A Fine powder spray was done on the Horse to make it dull but in such a way that the details can be viewed with the webcam... My Laser is mounted on 1:256 Gear box that is driven with stepper motor... I am using DIY SLA7062M based stepper driver that can run the stepper motor in 1/2, 1/4, 1/8 and 1/16 microsteps ... To get the fine details at 800 x 600 camera resolution and 150mm calibration scale using green line laser i changed the microstep mode from 1/2 step to 1/16 steps.. Now I have resolution of (200 x 16x 256 =819200 pulses per one complete rotation i.e.0.000439 degrees/step ). This resolution is fine enough to get the Horse details from 3meters distance from the Webcam...However i have kept the horse about 300mm far from the Camera ...Following are 4 multiple scans of the horse:

The results I found were satisfactory as the Webcam Logetech9000 has the limit... To get more fine details I have to do:
1- To get expensive CCD Monochrome camera
2- To get fine green line laser that should be focusable

[khalid]

Recently Oisin asked me to scan some fruit so that he can see the results... I just plucked an orange from the tree and did two scans... Now you can comments about the quality of the scan...

[khalid]

Here is the video of CNC machining of the scanned Rooster by Waynee Hill... Waynee used Vectric Cut3D for toolpath Generation...
http://www.youtube.com/watch?v=eT25spN4ulw