Is there anyway to 3d scan a car's dashboard using cheap method with 1mm accuracy ?

[Calico]

I wonder is there is a way to scan a 3D say ... a dashboard of a car with good accuracy (1mm accuracy) ?

I know portable 3D scanner like Microsribe is at least U$2000, way expensive.

how about using a regular camera ? still not accurate enough ?

all I need is reverse engineer of a dashboard to my cad program with 1mm accuracy.

cal

[Mono Sodium]

a camera picture is 2D not very practical !
I redesigned my dash by ripping the old one out and using the existing mounting points from the dash i ripped out, then cutting away bits from the old dash and fibreglassing and using expanding foam to sculpt what i wanted into a positive mould. then created a negative from that, then layed up a clear gel coat and carbon fibre finished dash. much easier than tring to design one on cad from a laser 3D scan!

[High Seas]

Well, I'm somewhere in between each of you 2 guys!

Calico -- I'm starting with my doorskins - and, yes I used the digital camera. But, I'm using it for making accurate background maps for using with the CAD app. That way I get an accurate layout of the boundaries. With patience (after removing the 'skins) I suppose you could so in all 3 views - (or more).

There are a couple of camera - laser apps but they tend to be small size - at least in the low budget range and the DIY digitizer arm is still on hold in the forums.

Mono Sodium - care to share a photo of your processes and final efforts? I am thinking of trying the "touch probe" and Mach to sample the backside of the 'skins to model that side. Ambitious doing the dash! But that will follow in time - more fun than putting a stock one back in after my bro-in-law burned up the last one!

Jim

[svenakela]

http://www.cs.tu-bs.de/rob/david.html

[GAWnCA]

Svenakela,

I've seen this before and want to know what webcam camera is best suited for this typr of scanning? The general recommendation is pretty vague.

Thanks,
Greg

Originally Posted by svenakela http://www.cs.tu-bs.de/rob/david.html

[svenakela]

Originally Posted by GAWnCA Svenakela, I've seen this before and want to know what webcam camera is best suited for this typr of scanning? The general recommendation is pretty vague. Thanks, Greg

I believe it's usable with anything, but send an e-mail to them and ask.

Regards,
Sven

[GAWnCA]

Sven,

I did once before and never received an answer. What camera are you using, if any?

Greg

Originally Posted by svenakela I believe it's usable with anything, but send an e-mail to them and ask. Regards, Sven

[High Seas]

The challenge to using the DAVID software is the calibration circles/dots need to be there during calibration & SCANNING. SO, get ready to size up that calibration grid from 8x10 inches - to???? I think that is a bigger challenge than getting the right cam.

Likewise the SCANZ(ed) Bruce was putting together requires a turntable - so that needs upscale too. Thats why I'm looking at using the MACH2 and a probe. Could take a long while to get the point cloud - then there is converting to 3D. My head hurts!
Jim

[svenakela]

I've just tried it a little bit, so I can't say I know much about it. Maybe you can scan the object in partial scans and put them together?
Probing or scanning? I think they all have their issues. Either it's money or time.

[keitholivier]

Find someone near you with an articulated arm measurement system (romer or Faro arm). These arms can be bolted to anything and then are scanned "by hand" over whatever object you need to capture. Each time you want to record a point, you touch the stylus to the object and push the "record" button. To scan more points, hold down the record button and drag the probe over the surface.

I would caution against capturing too many points. It makes the job of fitting surfaces later more and not less difficult. If you intend on changing the dash, you only need basic info on the existing dash (where the edges are, the plane of the instrument panel and the position of services that cannot easily be moved. Then remove the instrument panel and scan the steel below it in more detail, since this is a "hard" boundary. Find the attachment holes/tappings and scan both the center point as well as the plane of the surface (together that gives you exactly the axis of the fastener). This kind of point is pretty unforgiving, you have to get it exactly right or deal with a loose rattly and vibrating panel afterwards (fate worse than death)

These kind of CMM's sold relatively cheap ($30k), are good to about .01" which means that they are not the most highly worked part of the average shop that owns them. Sometimes a call to the rep for Faro or Romer in your state will get you pointers regarding local companies that have the equipment that you could work with.

Keith

[fergusda]

The best way to digitize a dash board is a self positioning scanner like the ZCorp or Creaform scanner. $30,000+. Romer/Faro arms have trouble moving around in a car interior.

For the cheap DIYer:

1) Buy a cheap laser line tool. Position it (on the headliner?) to project a straight horizontal reference line across the bottom of the dash.

2) Use tape to draw straight vertical cross sections across the dash at regular increments (say 1"?).

3) Buy a cheap 12" profile gauge at Harbor Freight tools.

3) Position the top or bottom of the profile gauge on on the laser line. Press the profile gauge to the dash at each tape line, and scan each profile with a flatbed scanner.

4) Scale the images correctly, and trace each profile as a 2D spline/line/curve section in Rhino (free trial) or any CAD package that can import Bitmap images (like photo scans).

5) Create surface patches from the curves in 3D CAD package.

This will give you a basic outline of the dash shape. You can add additional detail with manual measurements to get a more accurate model.

It is a lot of work, but sure beats spending $30,000 only to find out there is still a lot more work.

-Dan
Global Inspection Solution
www.globalinspectionsolutions.com