Laser

WebcamTurntable

Low cost 3D scanner

Costs:

• Laser………….100euro

• Webcam………100euro

• Turntable……...150euro

Side viewTop view

Object

• In order to perform triangulation (line-plane intersection) all the devices must be calirated.

• 3D handmade grid cube with known 3D position

The detected points are the measurements

• Camera Calibration

Detected laser line with known world position.

• Laser plane calibration

• Laser with cylindrical lens.

• Subpixel peak detector

• Laser plane orientation is finally computed.

I Wx PxIx

Wx

0 50 100 150 200 250 300 350 400 450 5000

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• Turntable calibration (time)

• Turntable calibration (space)

• Point detector

• Ellipse detection

• Ellipse fitting

• Imaged center

Assumption:

• Uniform Sampling

• Low jitter

• Constant velocity

Frame Number

SSD

SSD (summed squared difference) all frames wrt the first .

• Recontruction by Triangulation.

• We use the DirectShow API to acquire the video sequence. 320x240pixel 30fps

• And OpenCV for basic image processing.

• Point cloud

• Triangulated mesh

• Point cloud • Triangulated mesh

• Application: Orthopaedic Shoemaking Ortopedia Fiorentina (Firenze).