3D Laser Scanner

    At the beginning of this mystery project that I worked on, during my first semester at Navajo Technical University (NTU), I was asked to complete this project with another student if I needed an extra set of hands. I also worked with another student that was proficient with AutoCAD who was asked to create whatever I needed to complete this project. The last instruction given: complete this project in three weeks. 

                             Above: The completed laser scanner ready for the maker faire

The following is the process of how we were able to create a 3D printed, 3D laser scanner. 

Although this project was created from designs from this Instructables project, we did not had access to some of the hardware indicated in that project.

Software: The software for this project was created beforehand. Without any type of user manual, or written instructions on how the software would interface with the hardware. The software also included code for instructions for the microcontroller to rotate and turn line lasers on sequentially during the scanning process.

Hardware: A donated Arduino Uno, with a motor driver, webcam and line lasers. All structural hardware was created on site due to time, and shipping constraints. 

Initial Thoughts
My first thoughts of a laser scanner were using the line lasers to capture image data and output to the Arduino, then the webcam would just sample colors from the image. 

Scanning
Through the efforts of trial and error, my understanding had grown immensely in the two weeks that it took to build the unit.
1. The object that we want to scan is placed at a point where the laser lines intersect (the center of the turn table). 
2. The software then asks the controller to turn the object five degrees, fire the line lasers on the object with a sequence.
3. The webcam captures an image using the IR sensor and gathers texture information from the image data. 
4. This is then displayed as a 3D image using the software user interface.

A very simple process that has a complicated backend. 

To achieve a near perfect scan, a couple of conditions were to be met.
1. The object to be scanned should not be reflective.
2. The area around the scanner should be dimly lit.
3. Smaller objects were easier to scan, as oppose to objects that took up most of the turntable.

A couple of photos of the project in various stages

Here on the left is an example of the 2020 profile that we printed, next to a 2040 profile that was found later.

On the right, the lasers are all on to demonstrated the intersection.
At the time I did not use screen capturing software, but as you can kind of see there is a dark monitor demonstrating low light scanning.
Wiring and testing lasers on the scanner. In this picture you can see the Arduino, motor driver, and stepper motor mounted at the base.
Demonstrating lasers on the side of a box.

Figuring out how to scan a Rook chess piece.






In summary this project had taught me lessons in project management, programming, verifying code, circuit design, hardware integration, and most importantly: diagnosis of electrical hardware, software. 

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