Space Ocarina
This device is a simple circuit consisting of a 556 timer, a series of capacitors and resistors, and a speaker. Four photoresistors vary the circuit's resistane and thus the pitch emitted by the circuit in response to light exposure. I designed it as a musical instrument, and it does in fact play a minor mode between the keys of F and F#, but most people just wave it around.
Recently, an expert on autism who works daily with autistic patients commented that it could potentially serve as a soothing device for her patients, who frequently become overwhelmed when their surroundings begin to feel out of control. The sound emmitted by this device, though probably not very soothing for most people's ears, is under the complete control of the user. I am currently looking for opportunities to humanely test the Space Ocarina with autistic users.
Description of Device
The housing for this device is a simple plastic egg, commonly used to contain candy or other treats for Easter egg hunts. Because the egg is already hollow, it can hold all electrical elements of the device, including the speaker and battery. The circuit in this device is a basic Atari Punk Console, except in place of Potentiometer 1, I used a 120 K Ohm resistor to limit the range of tones that the Ocarina can play. In place of Potentiometer 2, I used 4 photoresistors wired in series, which are set on the outside of the housing and function as "buttons" to alter the tone emitted by the speaker. The speaker is hot-glued into the rounded half of the egg, and because the egg closes around it, the circuit's abrasive sound is dampened and the device sounds better as an instrument. The wiring to and from the photoresistors and speaker runs along the inner circumference of the egg to maximize space, primarily to fit the battery, which can be attached and unattached to a snap connector. Each half of the egg accommodates two photoresistor buttons, and for this reason and to allow for future repairs, the Ocarina can be easily opened and closed without significantly disturbing the inner components. The Ocarina can be turned on and off by means of a toggle switch set into the more pointed side of the egg.
Affordances Hypotheses, prior to user testing
Even while switched off, the Space Ocarina immediately attracts attention because of its reflective gold surface. Additionally, a potential user's curiosity would be further intensified upon recognizing its resemblance to the standard "Easter egg" but also noticing the photoresistor buttons on its outside. The photoresistors themselves invite users to touch them, and when the device is turned on, touching or even moving one's hand over the buttons results in immediate feedback (the tone changes). Because interaction with the photoresistors varies the tone in distinct, recognizable intervals (3rds, 5ths, and octaves), the device is recognizable as some kind of instrument. The buttons are also positioned so that a user's fingers can rest comfortably on them while holding the device, and though it can be operated while sitting at rest on a flat surface, the size, unstable "roll-ability," and general aesthetic consistency from all angles invite users to pick up the Ocarina.
Once a user sees that the object resembles an Easter egg, one of his/her immediate inclinations may be to open it. The inner components clearly establish that it is an electrical device, and this will hopefully lead a user to quickly re-close the egg and return to interacting with the outside of the device. I considered hot-gluing the egg together, but I ultimately decided to leave the inner workings accessible in order to change the battery and for potential repairs. The device's inner components are well organized, so changing the battery is very easy to do.
A secondary use of the Space Ocarina could be as a garden and outdoor decoration. If left turned on and in a partially sunlit area, the tones emitted by the device will develop and change gradually over time. Two to three of these devices can work together to form chord combinations if they are exposed to different amounts of light. These chords will shift as the light changes throughout the day, varying and contributing to the "mood" of a space. Generally, two Ocarinas will emit tones that agree with each other musically at times, and an experienced user will know how to place each device to achieve a desired chord. Feedback in this regard is instant, and the ability to vary the intervals between individual Ocarinas invites experimentation, especially for an unfamiliar user.
The simple appearance of the Ocarina is important; there are only 5 items to interact with. The 4 photoresistors give instant feedback as described, and the only other visible component is the toggle switch, which should be figured out quickly by most users. The device looks like an instrument, and after installing the toggle switch, I realized that holding the egg with the pointed end up and closest to the user's face makes the switch look like some kind of mouthpiece. Hopefully, users will not try to put the switch in their mouths.
Assembly and a comment of the nature of electricity
In order to fit all electrical components into the egg housing, the circuit had to be as compact as possible. Achieving this constituted much of the work and experimentation that went into this project. Schematics tend to reflect the subjective understandings of electrical circuits as their creators most easily conceptualize them, so my task was to minimize the amount of wiring that I initially saw as necessary from the schematic we were first given. In thinking about this, I was able to determine that each connection from the 556 timer's pins to power, ground, or to another pin could be made using a single component (with the exception of pin 9's connection to ground through a capacitor and the speaker, as well as pin 12's connection to power through 4 photoresistors in this particular design). The connecting component could be in the form of a jumper wire, resistor, capacitor, or even pure solder. This statement may seem somewhat transparent, but working continuously on a breadboard allowed me and compelled me to think about the APC circuit in terms of the connections I counted between nodes in the schematic. The experience of building the circuit without the breadboard's accommodation of sprawling, indirect connections and imposed sense of structure, along with the goal of building a very small circuit, led me to understand the circuit's framework in a different way. It originally seemed to me that parts of the circuit where several components connected together needed to be wired according to the order implied by the original schematic. However, after nervously powering my first free-soldered circuit and finding that it worked, I understood that the circuit's structure could be described as a network of interconnected hubs, each of which is composed of 1 to 5 in/outputs. As long as power is applied in the appropriate direction, electricity will be present throughout a correctly connected network.
A Follow-up on Affordances
Having officially presented the device, I have occasionally been testing its affordances with people who are unfamiliar with the project. My initial prompt has usually been to set the device on a table and say to someone, "Interact with this." Rather than editing my original statement of affordances, I think it is more productive to keep record of my expectations and compare them to my observations below.
1. I was correct in thinking that some people would be inclined to open the egg. However, the test subject who opened it became interested in the wiring and continued to poke at and examine the interior components. I am not sure how to resolve this while allowing for the battery to be changed.
2. The battery's weight causes the egg to lay at rest with the photoresistors turned at a downward angle, hiding part of the peculiar aspect of the device. This is easily solved by arranging the inner components so that the battery sits inside opposite the photoresistors.
3. Some people's first statement was that the Ocarina looks like some kind of explosive device. The addition of the switch does make it look a bit like a grenade. However, most people recognized the switch and turned the device on, which gives immediate feedback.
4. Intitially, I anticipated and intended for people to be confused and curious about what the device is, but as I actually built it, I thought of it more and more as an instrument. No one who interacted with the device explicitly identified it as an instrument, which is really not surprising. Adding a component to the circuit to soften the sound further could help with this. Also, placing the photoresistors in a pattern that better reflects an intuitive mental model of an instrument might help as well.
5. Though people quickly realized that the photoresistors did something, few attempted to control its tone by experimenting with the buttons. I believe this is due to the fact that it is not easily recognizable as an intended instrument, as well as to the problem that people did not seem to realize how the photoresistors work. (Some tones can be played by hovering over a resistor.) While making full contact with one or more resistors clearly provided feedback, people did not seem to connect this with the variance of light exposure.