3D Laser Scanner using Turntable

3D scanning turns a physical object into a digital model, and laser triangulation is the workhorse principle: shine a laser line at the object, watch from an angle how the line bends over the surface, and geometry gives you depth. Commercial scanners hide all of this; this project exposes it. A wooden turntable driven by a NEMA17 stepper (through a DRV8825 driver and Arduino) rotates the object in fine steps. A red laser line module on a vertical column throws a stripe across it, and a USB camera captures each stripe profile. Python software extracts the stripe centerline per frame, applies the triangulation math from a one-time calibration, and assembles the point cloud. The student sees every link in the chain — mechanics, control, optics, calibration, processing — and the report discusses accuracy honestly, as a function of calibration quality rather than a claimed figure.

1. The object is placed on the turntable; the laser line module is aimed so the stripe crosses it, and the camera is fixed to view the stripe at an angle.
2. The student runs the one-time calibration with a known target, fixing the camera–laser geometry parameters.
3. The Arduino rotates the turntable by one step and signals the PC, which captures the stripe image.
4. Python software extracts the bright stripe centerline from the frame and converts each stripe point to a 3D coordinate by triangulation.
5. Steps repeat for a full revolution, accumulating profiles into a complete point cloud.
6. The point cloud is exported, viewed in 3D software, and compared against manual measurements of the object for the report's accuracy discussion.

Tech stack:

• NEMA17 stepper motor + DRV8825 driver
• Arduino Uno (scan control)
• Red laser line module
• USB camera
• Python (OpenCV) processing
• Wooden turntable + aluminium column
• Point-cloud viewer (free software)

• [Stepper-driven turntable] A NEMA17 motor indexes the wooden platform in fine, repeatable steps through a DRV8825 driver — the scan resolution is set by the step angle the student chooses.
• [Red laser line module] A line-generating laser on an adjustable vertical column projects the measurement stripe onto the object — the triangulation light source.
• [Arduino scan control] The Arduino sequences rotation steps and signals the PC per frame, so capture and motion stay synchronized.
• [Triangulation processing] Python software extracts the laser stripe from each frame and converts stripe displacement into depth using the calibrated camera–laser geometry.
• [Point-cloud output] The assembled scan exports as a standard point cloud the student can view and measure in free 3D software.
• [Calibration procedure] A documented one-time calibration with a known-geometry target establishes the triangulation parameters — the step that determines scan accuracy.
• [Adjustable scan resolution] Step angle and frame count are configurable, so the student trades scan time against point density and documents the tradeoff.

• Working turntable 3D laser scanner rig
• Arduino scan-control firmware
• Python capture and triangulation software
• Calibration target and calibration procedure
• Mechanical assembly drawings
• Project report PDF (triangulation theory, calibration, scan results)
• PPT presentation for final review
• Viva Q&A preparation document

• Accuracy is a design target (~1 mm order), not a measured claim — it depends entirely on calibration quality, camera resolution and ambient light, which the report discusses honestly.
• Matte, opaque objects only; transparent, mirror-shiny or very dark surfaces defeat the stripe extraction.
• A full high-resolution scan takes many minutes — scan time vs density is an explicit tradeoff.
• The laser is low-power but the manual includes standard laser-safety precautions.
• Point cloud only as shipped — meshing and cleanup are done in external free software, documented as a step.