Seat Indicator

The second low-fidelity prototype was a seat availability indicator. Given the still ongoing COVID-19 pandemic, many places, such as theaters, football stadiums or lecture halls, used stickers or other indicators to indicate whether a seat was supposed to be used or not. However, given the everchanging rules, this might result in a lot of manual work, so the idea was to create a small solarpower driven display that would either show the place number or an unavailable icon and could be controlled wirelessly. Displays for this were printed, and even some frame was designed. However, given the potentially high price, and small commercial potential the idea was at this point rejected.

Customizable Phone Case

After seeing some of the demonstrators that used the power transmitted via NFC to power an EC display (besides others the participants were exposed to), several participants developed independent from each other, ideas and concepts around a phone case that would contain an EC display. The display could than act either as an aesthetic addition to the phone or as a notification element. The notification idea stemmed from the fact that the participants observed that several of them had their phone with the display down (some here mentioned privacy as a reason for this behavior) and so they only would be able to see notifications if they turned the phone around (or if
they had vibration or audio tones enabled which they considered rude in this setting). The display would simply change slowly whenever they receive a notification and thereby be a very undisruptive notification mechanism. Besides this, it could also simply be an aesthetic element and particpants discussed the idea of being able to quickly switch out the display for different seasons etc. or to fully have a custom display that is individually ordered by a person in the case.
To realize this idea, participants borrowed a phone from LAY and quickly downloaded an example case from thingiverse.com. After ensuring that creating the case would be no issues, they started prototyping the electronics. Here holding the event at LAY really made it easy for participants to get access to all needed electronics. The participants used an Adafruit ST25DV16K NFC tag, that allowed to harvest the NFC power and drive one of VTT’s custom display driver boards (ATTiny 85 based) to control the display to switch regularly whenever the NFC of the smartphone is powered on. After ensuring that the electronics where working the case was customized to accommodate for the electronics and the display. It was designed to easily switch out the display. As a first design the participants used a motive that was heavily inspired by the ongoing arctic design week. The overall prototype could easily completely be based on printed electronics if wished for, given the experience of the DecoChrom consortium. However, first further evaluation of the cases social acceptability is needed to understand the potential impact.

Shake Display

One of the participants brought a Batteryfree – Million Mile Light1, which is a device with four small LEDs connected to a capacitor that is connected to built-in linear moving-magnet generator with stationary coil. This means that it can be operated completely battery free and in theory last forever. The device is very similar to the original Shake Light (for an analysis of the technology see [2]), which allows to shake a flashlight for some time to afterwards power it from the generated energy. The participants were inspired by this technology and the possibility of creating a truly battery-free device that uses EC displays. Several ideas were quickly sketched on where this could be used, e.g., as an indicator on a cocktail shaker. But more serious application-oriented scenarios were developed as well, such as an indicator for a spray can whether it has been shaken enough to use the can or also applications for other chemicals or medical supplies that are supposed to be shook before they are used. It was decided to develop a prototype of a shake indicator for a spray can as this was easily accessible to participants. After a short internet search of the inner working of the device, several participants started prototyping a small enough linear moving-magnet generator, that would fit into the cap of spray can. It took several 3D prints and experimentation with different coil thicknesses and different magnets before the generator would fit the profile of shaking it for at least 1 minute (the recommended shaking time for a spray can) before an EC display completely switched (as a matter of fact, most prior approaches allowed an EC display to switch quicker than that, therefore it represents a quite interesting energy source for future applications with EC displays and should definitively be followed up on). This coil easily fit into the cap of a spray can and is able to activate and switch a display in around 70 seconds of relaxed shaking. The participants designed, and screen printed a display using two pictograms to indicate whether the spray can has to be shaken or it can be used. The display was added to the top of the lid and is driven solely with analog electronics (a switch and two diodes to switch polarity from the AC current delivered by the linear moving-magnet generator). The result is a fully functional prototype that would be extremely cost effective if mass manufactured.
To realize this idea, participants borrowed a phone from LAY and quickly downloaded an example case from thingiverse.com. After ensuring that creating the case would be no issues, they started prototyping the electronics. Here holding the event at LAY really made it easy for participants to get access to all needed electronics. The participants used an Adafruit ST25DV16K NFC tag, that allowed to harvest the NFC power and drive one of VTT’s custom display driver boards (ATTiny 85 based) to control the display to switch regularly whenever the NFC of the smartphone is powered on. After ensuring that the electronics where working the case was customized to accommodate for the electronics and the display. It was designed to easily switch out the display. As a first design the participants used a motive that was heavily inspired by the ongoing arctic design week. The overall prototype could easily completely be based on printed electronics if wished for, given the experience of the DecoChrom consortium. However, first further evaluation of the cases social acceptability is needed to understand the potential impact.