Earlier this year, I had the chance to work with the ETH plant science lab in Basel-Zurich to prototype a couple of new activities that combined a tinkering approach with plant-like robots that get power from the sun. I was intrigued by the idea of BEAM (biology, electronics, aesthetics and mechanics) which is a style of robotics that primarily use simple analog circuits instead of microprocessors to create simple behaviors. There are many resources online for building and understanding these project, but to me, as a non-engineer who doesn’t have much experience with electronic components, circuit diagrams or breadboarding, I wanted to find more accessible and low-threshold entry points.

As part of the project I worked on scrappy cardboard circuit boards that allowed us to spread out the components and more clearly show the arrangement of the elements. As well, I experimented with dissecting an existing solar garden light to make something new from the parts. And although the prototyping phase of the project has officially ended, as in most interesting tinkering activities, I can’t help but continue to build on the initial ideas and try out new experiments.

I’ve been inspired by a colleague, Amos Blanton of Aarhus University, who has been building solar powered art machines and automata with related designs. In his thought-provoking article, Playing with the Sun, Amos asks, “how can we create the conditions for play as a means to develop an intuitive understanding of energy.”

There are many interesting ideas here and one of the things that we’ve been wondering about together is how to highlight compelling and tangible examples of solar power in real life that can inspire tinkering explorations. So with that in mind, I’ve been keeping track of interesting art works and examples around the local area here in Freiburg im Breisgau, Germany, as I continue thinking about these ideas.

A good place to look for tinkering inspiration is from existing toys. I was at the farmer’s market at the local Munster and these solar helicopters caught my eye. I think it’s interesting how the solar panels and motors are joined in a combined unit that rotates freely. So, I ordered a couple elements from Sol-Expert and am looking forward to experimenting more when they arrive to make scrappy versions of these creations.

Another local landmark that I found is the Heliotrope, designed by the German architect Rolf Disch, which is the first building in the world to capture more energy than it uses. Interestingly, the whole building rotates to continuously capture as much energy from the sun as possible. I think this could be an inspiration for many different types of tinkering projects with more simple arrangements like this solar tracker.

And of course, I have to mention again the art of my friend Claus Schneidereit who creates large scale kinetic automata, many of which are solar powered. I really like how he creates his own circuits based on broken pieces of solar panels. I think these large units could be really interesting tools to show ways to tinker with generating power.

With all of these ideas and inspirations in mind, I’ve been building on the solar circuit boards and testing out versions of little BEAM creatures on the balcony and in the park. I took the circuit from our solar engine instructable and used copper tape to fit it to a couple old chocolate bar and soap boxes. It was fun to re-design the circuit to fit on a specific surface and experiment with different types of solar panels and capacitors.

Then I took the bots over the Claus’ workshop and although it was a bit of a cloudy day, we could test out the machines using big mirrors to increase the movement, an idea inspired by Amos’ art machine workshop. I really like how this simple step can include more participants in the activity, give people an initial embodied understanding of how the machines work before building and add a layer to the investigation.

Then we headed to the shop and started on a new version of the project that used a prototype circuit board instead of the cooper tape. Claus helped me by using a software that mapped out the copper tape circuit onto a prototype which is something that has been a little bit difficult for me to conceptualize. The process was really easy and it was so cool to print out the design, glue the paper to the protoboard and then solder the components and bridges in place. We of course had to then test to make sure that everything was working correctly.

We added three ports (little metal sockets) so we could be able to simply add and exchange different solar cells, capacitors and motors. I really like this approach, because it allows learners to quickly experiment with the way that solar energy creation, storage and release works.

For example, depending on the size of the capacitor, the system works really differently. With the “standard” 4700uF capacitor it charged in sunlight for about 5 seconds and then the motor turned just for a bit (maybe .5 seconds). We added a much larger capacitor and it charged for about 15 minutes but then the motor turned on for about 20-30 seconds. These different behaviors can be used directly for unique robot creations.

The next steps for the project will be continuing to try out different configurations of components and adding ways for people to explore, iterate and collaborate more easily. As we were doing research, we also found out that the type of trigger (one of the parts of the solar engine circuit) also can really change the behavior by setting the voltage ‘limit’ where the system discharges the electricity. I’d also like to experiment with the connection points so that it’s clearer and easier to know what component goes where and to get the polarity to be consistent. These little tweaks can make the project more ‘tinkerable’ and will help encourage others to play and create with the components.

Solar Robots and Eco-tinkering Inspirations