Creating new activities and resources like activity guides are key parts of the Facilitating Computational Tinkering (FCT) Project. But what do you do when you discover something cool that isn’t quite ready to be turned into a guide? My answer is this: a “case study”. A case study documents the cool things we’ve learned with a good amount of detail in hopes that someone else might want to pick up these ideas and continue to tinker with them. This approach to sharing in-progress ideas is inspired by FCT collaborator the Tinkering Studio’s wonderful blog, which is described as a “virtual sketchpad to share our half-baked ideas and works in progress”.
Case Study: Tinkering with Scribbling Machines and Computation at Rodolfo “Corky” Gonzales ideaLAB
A while back, I collaborated with Carly and Ammon at the Gonzales ideaLAB at Denver Public Library to create and facilitate an “Art Machines” workshop for ideaLAB visitors. We were inspired by the “Scribbling Machines” explorations shared by the Tinkering Studio which combine motors and markers to create motorized contraptions that create unique marks. The full workshop consisted of several activities, including giant cardboard spirographs and two versions of scribbling machines. For this case study, I’m focusing on and sharing more about one specific element of our workshop: scribbling machines created with programmable motors.
A scribbling machine made with a non-programmable hobby motor.
A scribbling machine made with a programmable motor (hidden behind the marker) which is connected to a microcontroller called the Circuit Playground Express (pictured on top of the scribbling machine).
The scribbling machine activity, as described by the Tinkering Studio, emphasizes actions like tinkering with physical variables such as the number of markers or how the motor is attached and typically uses non-programmable hobby motors (pictured above). We wanted to build on this idea and invite participants to tinker with code and computational variables such as the speed of a programmable motor (pictured above), or leveraging inputs like sound or light to trigger actions like turning the motors on and off.
An illustration of the system of components we created to make it easier to connect the Circuit Playground Express and motors to our scribbling machines
To make tinkering with code and scribbling machines more accessible for workshop participants, we created a system for connecting markers, craft materials, motors, and Circuit Playgrounds together that consisted of cardboard, brass fasteners, and pipecleaners. You can read more about how, and why we created this system here: https://dl.acm.org/doi/pdf/10.1145/3591196.3593369 .
Now that you have some context, I’ll highlight a couple of the example computational scribbling machines that we created for workshop participants. Examples play an important role in a workshop. They can help participants understand what’s possible, and spark new ideas. As a designer of educational experiences and activities, I love seeing other educators’ example projects because it gives me something to explore on my own to learn more about the activity.
Computational Scribbling Machines
This video introduces you to the two example computational scribbling machines we created for this workshop. It also models some of the tinkering and experimentation we went through when creating and testing these machines, which we hope participants experience as well.
Example 1: Light-Sensitive Scribbling Machine
This is a “light-sensitive” scribbling machine. We created this example to show how our scribbling machines can respond to the environment, and how we can interact with a scribbling machine without touching it. We considered a sound-activated scribbling machine, but the volume levels in the makerspace varied too much for that feature to consistently work well.
A Closer Look: The Code
We tried to keep the programs for the scribbling machines fairly simple so that participants could easily understand and tinker with the code. For the workshop, we created handouts that explained key pieces of the program and identified places where participants could change the program such as the value in the “pause” block.
This program uses an “if statement” to check to see what the light level is. If the light level is greater than 200 (255 is the maximum value the sensor reads, this would be a super bright light pointed right at the Circuit Playground), then the servo motor moves to a specific angle (135 degrees in this example). After 1 second, if the light level is not greater than 200 the servo motor moves to a different angle (35 degrees in this example). What does this look like in action? Revisit the video above. When someone points a flashlight at the circuit playground, it moves the marker. And when the light is taken away, the marker moves back. This back-and-forth movement triggered by the light causes the marker to swipe the paper.
You can click on the embedded code example to the right to open the program in the MakeCode editor to take a closer look, or to download the program.
A closer look: how it’s made
If you’re wondering how to build one of these machines, take a look at this video. There’s no one “right” way to build a computational scribbling machine. It’s up to you to try different ways of connecting components together. This video shows me deconstructing and reconstructing the light-sensitive scribbling machine so you can see some of the materials and construction techniques I used, such as using rubberbands and pipe cleaners to securely connect materials like markers and cardboard.
Example 2: Button-press Scribbling Machine
This scribbling machine uses a button press to affect the speed and direction of the servo motor. This example was created to show what it looks like to use a “continuous” servo motor with a scribbling machine. A continuous servo motor is one that keeps turning, unlike the “positional” servo motor used in the previous example which moves to a specific angle of rotation and then stays still.
A closer look: The Code
This program is activated by pressing the “A” button on the front of the Circuit Playground Express. When the button is pressed the servo motor will turn in one direction at 80% speed for one second, then it will turn in the opposite direction at 80% speed for one second. This cycle repeats 5 times. Revisit the video above to see what this looks like.
In the handout we created for the workshop, we encouraged participants to tinker with variables like speed by changing the numbers in the “continuous servo run” blocks, the duration of the pause, and the number of repeats. We also invited participants to try a different input block instead of “on button A click”.
A closer look: how it’s made
The construction of this computational scribbling machine is pretty similar to the previous example. A mix of pipecleaners, rubber bands, cardboard connectors, binder clips, and brads are combined to create unique mark-making machines. If you try out this activity with your learners, consider experimenting with materials and tools that are relevant and accessible to your unique community.
Conclusion
After reading this case study it might seem like we have everything figured out and you may wonder why this isn’t ready to be turned into a full activity guide. One reason for this is that we didn’t get a lot of feedback about the computational scribbling machines from participants during our workshop. There weren’t many participants in the workshop, and of those participants not all engaged with the computational machines. It’s important to go through a process of gathering feedback from participants, reflecting, iterating on the activity design, and testing the activity again in order to improve the experience. In addition to having limited participant feedback, we have also not had the opportunity to test this activity again with learners. More cycles of testing and refinement are needed before this is ready to be turned into an activity guide.
I hope this case study creates a spark that inspires your own experiments in tinkering with code and scribbling machines! For more information about the Facilitating Computational Project that this case study emerged from, including a variety of resources and activity guides, visit facilitatingcomputationaltinkering.org
This material is based upon work supported by the National Science Foundation under Grant No. 2005764, 1908351, 2005702, 2005731