David

[link removed not existent] is a very low cost sensor system introduced by Dr. Simon Winkelbach and Sven Molkenstruck. It utilizes a standard USB webcam and any sort of hand held laser line projector. This article is about my first impression of the sensor system and the discussion about how to integrate the data into FreeCAD.

Hardware

Sensor

I use the follwing hardware for the scan:

• A 10€ Laser line from the hardware store
• A 24€ Trust WebCam 640x480, 17 fps

• 

  Laserline 10€

• 

  Webcam 24€

Test parts

I will use follwing test parts:

• 

  Walter Cube

• 

  Moebius-like band

• 

  CAD test part

Setup

Here is my sensor setup for the first two test parts. It is a corner with a 90° angle and two sheets with the calibration pattern.

Software

So far I use:

• The DAVID sensor wizard
• FreeCAD for post processing

Scans

Here are the scans I made with the sensor.

First tryout

This is my first tryout with the above mentioned sensor hardware:

• First Scan with .OBJ and cleaned .STL files.

• Impressions of my first scans
• 

  Bottle raw

• 

  Bottle

• 

  Bottle detail

• 

  Bottle interpolated

• 

  Walter cube top

• 

  Walter cube side

• 

  Walter cube with sphere fit

ToDos

Here some ToDos to enable FreeCAD to easily incorporate DAVID scanner data:

• A DAVID Workbench
• Own hole closing filter
• ...

Done

The following DAVID related features are allready implemented:

• OBJ file format import (Rev:358)

Scans from others

Here a list of published scans from other persons (with no warranty ;-).

Roberto

Example

Finished model of a little dog

Hardware

MICROSOFT Webcam LifeCam NX-6000 USB 2.0 - 2MB pixel captor works very well in 800×600 at 30 fps grey scale(no saturation), the scan is precise to 0.1 mm (180mm model)with very few noise for 82 Euros wonderful.

Software

Only free software has been used

• DAVID
• MeshLab (noise remove)
• Scanalyse (assembly)

Weblinks

• [dead link removed]