9. Output Devices

This week, I wanted to use the servo motor as it is a crucial element in my final project. The idea is simple. The servo motor will be used to open and close mini doors on my board game map.

Process

I started out by refering to this youtube Here and understood how a rack and pinion can help convert the rotational motion of the servo into linear motion.

Next up, I downloaded the Mini Versions of the Rack and pinion, and the servo holder STL files from the Thingiverse link on the above mentioned youtube video. Here is a link to that:
https://www.thingiverse.com/thing:3170748/files

Next, since I wanted to use a door at the end of the rack, I popped open a bottle of Fusion 360 and began making my door. I started with a very basic door design- the kind you would see in typical cartoons or TV shows.

Next, I thought about making a more “flavored” door, meaning that it would have more character.

I took the reference of Medieval castle doors which are usually made of metal, such as this:

Along with the doors in the Fire Nation empire in one of my favorite shows- Avatar the Last Airbender.

I went on to make this door on fusion based on these two references:

I then combined my door to the end of the Rack model I had taken.

Quick tip here: STL files are Mesh files. It gets a bit tricky to use mesh files on fusion has most of your other models would probably be Solid bodies. So what I usually do is convert the Mesh body into a Solid body before doing any operations on it. To do this, go to the Mesh tab of Fusion from the Nav bar above and click on “Convert Mesh” tool under the Modify option.

I also ended up modifying the Servo holder a bit as I decided that there was an extra few mm in the thickness which I didn’t need.

This I took to the 3D printer along with the Servo holder and Pinion STL.

Once the prints came, I attached the pinion to the servo motor and assembled the rest as well:

Hero shots

As you see here, the PCB that is connected to the servo is my Dev board which I had designed in week 8. Here is the link to that page to check out the design and production process of the Dev board: Sid’s Electronic Design

Working

For the code, I installed the <Servo.h> library. And under examples, I used the Sweep code example.

Project Files

Fusion Files
Basic door STL
Fire Castle door STL
Door + Rack STL
Modified Servo holder STL
Link to Original Thingiverse STLs
Servo Sweep Example code