by Donald Stump, Curriculum Director
It’s a challenge to use experiments, as the Venture does, to excite elementary-school students about science. One is always building new apparatus.
Our need, then, has long been for a highly versatile piece of growing apparatus that can be used, not for just one or two experiments, but for many. The problem is to develop a platform that allows a wide range of variables to be isolated for study in accordance with the scientific method. The solution, we decided in 2017, is a computerized growing chamber.
So-called “food computers” have attracted a good deal of recent media attention as processors for large-scale indoor farms, where lighting, watering, temperature, and nutrients are controlled to maximize productivity and quality. A few home units that can fit in a kitchen are also appearing. What has not appeared, however, are powerful, affordable classroom chambers. That is where we come in.
Using technology first developed by the MIT Media Lab, the Venture has for five years been working to satisfy our own need for such a platform. Large enough to accommodate side-by-side experiments in several growing systems (soil-based, hydroponic, and aquaponic), the unit must also be small enough to stand on a counter at the back of a classroom. Phil Speth, our inventive engineer and designer, initially made such a chamber using common materials and circuits driven by a low-cost, easily programmed Raspberry Pi computer to control a temperature sensor, fans, lights, a camera, and other accessories.
While testing this Phase 1 unit in our Ambassadors After-School program in 2018-20, we received funding from a local professional baseball charity, Cardinal Care, to install versions of it in the four schools that are our partners in the Urban Education Alliance.
Though Covid has so far prevented us from introducing new teachers to the equipment in our new Classroom Outreach Program, we hope to begin soon, helping them to set up and conduct their first computer-assisted growing experiments.
With construction of the Venture’s $4 million Education Center on the horizon, our next priority is to develop more powerful Phase 2 units. With the assistance of Prof. Sanjiv Bhatia, Professor of Computer Science at the University of Missouri St. Louis and member of the GHV Board of Directors, we are now seeking an intern to work with Phil Speth to reprogram current units and bring them back into service. We are also seeking a Raspberry Pi designer and programmer to develop a Phase 2 prototype able to turn lights of key colors on and off at pre-set times; control temperature, air flow, and watering; dose plants with precise amounts of individual nutrients; and control multiple cameras to monitor experiments remotely, sharing images with students, parents, and others interested in the project.
Using Phase 2 technology, teachers have many options. One might introduce the topic of flowering by designing an experiment around the effects of nitrates. Using the Raspberry Pi to inject different doses of that key nutrient into two growing trays, students could then collect data on the time of flowering and the number and quality of blossoms in each tray. Another teacher might place two aquariums in the chamber, each with rafts containing mesh growing pots floating on the surface. Plants grown with their roots immersed in an artificial and soon depleted hydroponics solution could then be compared with those in the nutrient-rich water of a more natural and regenerating aquaponic system. A third teacher might compare plants grown in soil rich or poor in compost. The possibilities are endless.
As Phase 2 goes forward, we are already thinking ahead to Phase 3, which will involve Cloud applications and Internet collaborations between schools. But that is a story for another day.