Introduction: RollTech

This assistive technology uses gravity and friction to activate and close circuits. It consists of a track that carries a ball along a 3D-printed course. The track has multiple closing points for the circuits. Each closing point triggers different keys and produces different actions. The conductive ball rolling along the track triggers keys by closing the gaps between the ground copper tape and the key's copper tape. I created this controller so that there was an adaptable tool that could be used with different attachments for optimal accessibility and functionality for all sorts of people. What I created was the base for all other designs to branch off of. 



Supplies


CAD FILE 

https://a360.co/3RACYkl


Interface for testing 

https://scratch.mit.edu/projects/editor


Link to remap Makey Makey

https://makeymakey.com/pages/remap

Step 1: Printing

Start by downloading the CAD file linked above. Next, use a 3-D printer to print the file. Once the print is complete, consider sanding some parts of the track to ensure smooth movement of the ball without any potential obstructions.

Step 2: Placing Copper Tape

After printing the file, take the copper tape and apply it along the inside of the four corners of the track. Use an exacto knife to carefully cut a slit along the center of the track, ensuring that the two sides of the copper tape do not touch each other. Lastly, wrap the marble in copper tape.

Step 3: Testing Conductivity

After placing the copper tape along the track, ensure that the two sides of the copper tape are not touching each other. You can use alligator clips and the Makey Makey to test and confirm that the circuits are not being activated. Once you've confirmed that the copper tape is properly separated, you can place your ball in between the slits created by the cut in the track. The ball's movement will close the circuits and trigger keys.

Step 4: Implementing Wires

Start by taking the wire and stripping one end of it. Thread the wire along the inside of the track, making sure it goes through each corner. At each corner, strip a segment of the wire to expose a small section. Take the copper tape and carefully wrap it around the exposed wire, ensuring a secure connection. To keep the wire in place, use hot glue to secure it along the track. Repeat this process for all four corners on the other side of the track. For better organization of the wires, make sure they all come out at one corner.

Step 5: Organizing Wires

Begin by wrapping each of your alligator clips with electrical tape. Ensure that you have one alligator clip designated for ground and four separate alligator clips for the keys.

Step 6: Labeling Keys

Take some tape and a marker. Label each of your wires with your desired keys. For example, you can write the corresponding letter or symbol for each key on the tape.

Step 7: Clipping Alligator Clips to Corresponding Keys

Now, it's time to test your controller. Begin by clipping each of the alligator clips to the corresponding Makey Makey keys. Ensure that each key has a designated alligator clip. Next, clip the other ends of the alligator clips to the labeled wires. Match each alligator clip to its corresponding labeled wire.

Step 8: Creating Attachment (optional)

If you prefer not to use the track by itself, you have the option to transform your controller into a joystick-shaped controller. To do this, you will need velcro, cardboard, and a ball. Attach one side of the velcro to the bottom of the controller, and the other side to a piece of cardboard. Place the ball on top of the cardboard and secure it with the velcro. This will create a joystick-like structure for more intuitive control. Additionally, if you want to make the controller more accessible, you can attach it to a hat using Velcro. This way, you can have hands-free control by simply wearing the hat.

Step 9: Remapping Keys (optional)

Click on the link attached above and follow the instructions.

Step 10: Setting Up Interface

Open the link provided, titled "Interface for Testing." In the interface, locate the section where you can set event keys labeled "when ____ is pressed.” Choose your desired key and click on it. Then, below the event key, select a movement key that you want to associate with it. Make sure that the event key and the movement key are the same to establish the desired control connection. Once you have set the keys, you can test out your controller by pressing the associated keys and observing the corresponding movements.

Step 11: BOOM DONE!