Alok Tayi, postdoctoral fellow in the George Whitesides Lab, Faculty for Arts and Sciences, and Daniel Kramer, College '15, were awarded a Student Sustainability Grant from the Office for Sustainability for the 2014-2015 academic year for their project entitled "Greening laboratories using Wi-Fi connected tools." Kramer and Tayi will document their experience and findings in a series of four blog posts that will cover: the conception of their idea, their initial prototyping and design challenges, testing in labs and lessons learned, and finally, an electricity audit and a report on savings.
When developing a new technology, constructing a functional prototype is the first step. For us, low-cost hardware platforms, like Arduino and Raspberry Pi, provide the sophisticated functionality needed to improve sustainability in labs. Given that our hardware was going to be deployed in a laboratory, we knew that there were several constraints: 1) the hardware had to be chemically resistant, 2) the software had to be reliable, 3) the electronics had to withstand large currents.
To this end, we purchased aluminum boxes (plastic will dissolve if exposed to certain chemicals), and coated them with a chemically-resistant coating. Surprisingly, we found a robust manufacturing base in the Boston-area that allowed us to source electronic components, machine and coat aluminum, and assemble the hardware quickly at moderate cost. We tested a variety of electrical components and configurations, numerous sized boxes, and machined patterns.
Inevitably, every design had its own pros and cons—some designs were easy to manufacture, but broke easily. Other designs were a pain to construct, but were low cost. We eventually settled on a combination of designs and electronics that allowed us to assemble Wi-Fi-enabled electric switches and Wi-Fi-enabled thermocouples with moderate ease.
With a housing chosen, the next step of the process was to integrate the individual electronic components. Our challenge has been that, though we use commercially available components, individual parts may be defective upon arrival. In one case, we were experimenting with different circuits for monitoring temperature (a thermocouple shield); however, despite our best efforts, the sensor reading was always incorrect. We debugged the firmware, software, and re-assembled the electronics to no avail. It turns out that the chip inside the thermocouple shield itself was faulty and the supplier sent us defective parts. Such experiences are commonplace in the world of hardware, unfortunately.
The generosity of the sustainability grant allowed us to experiment with these designs, work through the bugs, and produce three functioning prototypes, with the corresponding software. These tools allow us to monitor temperature of tools, stream video of experiments, and turn equipment on or off. So far, we’ve got these devices working in our space at the Harvard i-Lab. Next up—testing the designs with researchers in Harvard labs.