MIT Art, Culture, & Technology
MIT HearSay House Operation: Reykjavik, Iceland
Class #4.333: Höfði House / HearSay House
Professor Gediminas Urbonas of the MIT School of Architecture & Planning and his class of six students came up with some creative ideas for interactive art installations to be set in Iceland's Reykjavik Art Museum and the Höf∂í House. These projects concerned mostly the role of the Höf∂í House as a meeting place between Gorbachev and Regan during the Cold War. More information can be found here. My role was managing the technical design of each of these projects to make sure they worked and could undergo the stress of constant public use without electromechanical failure.
After the first iterations were installed in Reykjavik, some projects required maintenance and others needed sensors or networking to be fully functional. Below I have illustrated some of these projects and the design process behind each.
After the first iterations were installed in Reykjavik, some projects required maintenance and others needed sensors or networking to be fully functional. Below I have illustrated some of these projects and the design process behind each.
After the first iterations were installed in Reykjavik, some projects required maintenance and others needed sensors or networking to be fully functional. Below I have illustrated some of these projects and the design process behind each.
After the first iterations were installed in Reykjavik, some projects required maintenance and others needed sensors or networking to be fully functional. Below I have illustrated some of these projects and the design process behind each.
Breathalyzer Mapped to Weather Balloon Diameter
Yes, this is exactly how it sounds. This project connects two different locations in Iceland- the Reykjavik Art Museum (RAM) and Höf∂í. People at Höf∂i were served either whiskey or vodka, symbolizing their political standing as respectively American or Russian. The blood alcohol content (BAC) of each person was to be averaged over an hour and then sent over the internet to the RAM. Here at the RAM, an Arduino-controlled pump system would map the BAC to the size of its weather balloon. The higher the BAC, the bigger the balloon.
We needed to quickly prototype a cheap breathalyzer and a programable pump system.
We needed to quickly prototype a cheap breathalyzer and a programable pump system.
Programmable Pump System
This system went through two design iterations. Given the shortage of time on the first iteration, two different pumps (one AC and the other DC) were used to inflate and then actively deflate the weather balloon. The system worked initially and then failed a month into the installation due to an overload of cornstarch coming from the weather balloon. All latex balloon manufacturers coat their balloons in some form of cornstarch or power-like substance to prevent the rubber sides from sticking to one another, which could create a potentially fatal stress concentration. Flow rate calibration was also quite difficult given that we were using two different pumps each with its own volumetric flow rate.
So the second time around we bought two cheap Home Depot Bucket Head wet/dry vacuums and hacked them into our new system. I have used these vacuums many times and know that they can handle much more than a thin layer of powder. This new system used an arduino to control the amount of time that each vacuum was active for. The power switch for each vacuum was replaced with a solid state relay, which the arduino would then toggle on or off with a low power signal. To the right is a picture of the new system during assembly and below is a picture of the old system (on the right) and the essential parts of the new system (on the left).
So the second time around we bought two cheap Home Depot Bucket Head wet/dry vacuums and hacked them into our new system. I have used these vacuums many times and know that they can handle much more than a thin layer of powder. This new system used an arduino to control the amount of time that each vacuum was active for. The power switch for each vacuum was replaced with a solid state relay, which the arduino would then toggle on or off with a low power signal. To the right is a picture of the new system during assembly and below is a picture of the old system (on the right) and the essential parts of the new system (on the left).
Breathalyzer This device (below) is comprised of an alcohol sensor, 7 LEDs, a project box, an arduino and an arduino ethernet shield. The alcohol sensor requires more current than the arduino can supply, and therefore uses its own DC power supply. This sensor varies its resistance across two leads, which we translate into a voltage divider across one of the arduino's analog voltage pins. The higher the voltage read from the analog pin, the lower the alcohol content of the air around the sensor. Humidity, oxygen and temperature all adversely affected this sensor's readings. We successfully tested the sensor by wafting isopropyl alcohol vapor into the clear container, but unfortunately human testing was not an option until the device shipped to Iceland.
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Chair Pressure Sensor Mapped to Dot Matrix Printer
The concept of this piece of work was to visually represent the occupation of each chair used in the meeting between Gorbachev and Reagan as they discussed a possible treaty. When the chair with the black pressure sensor detected a person sitting, the dot matrix printer would print out a black square. Additionally when the chair with the white pressure sensor detected a person in it, the dot matrix printer would print out a white square.
If this project had started out using pressure as the main mode of sensing, or even a simple proximity sensor, then we would likely have been further along by the time we reached our deadline. However, we started this project by sensing the capacitance of the area above the chair, using an arduino connected to a woven pattern of conductive thread. Static electricity from the fabric ended up throwing off our time signatures for capacitance sensing so much that the system was registering occupation even when no one was in the room. Perhaps it was the ghost of Höfdí??
So I developed my own type of non-invasive pressure sensor that could comfortably fit on the chair without using glue, screws or any potentially damaging adhesive, AND was comfortable to sit on. The trick? Anti-static integrated circuit foam.
**More information is on its way, please check back again later!
If this project had started out using pressure as the main mode of sensing, or even a simple proximity sensor, then we would likely have been further along by the time we reached our deadline. However, we started this project by sensing the capacitance of the area above the chair, using an arduino connected to a woven pattern of conductive thread. Static electricity from the fabric ended up throwing off our time signatures for capacitance sensing so much that the system was registering occupation even when no one was in the room. Perhaps it was the ghost of Höfdí??
So I developed my own type of non-invasive pressure sensor that could comfortably fit on the chair without using glue, screws or any potentially damaging adhesive, AND was comfortable to sit on. The trick? Anti-static integrated circuit foam.
**More information is on its way, please check back again later!
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ABOVE: The chairs with their associated pressure sensors. Visitors are free to sit in these chairs at any time during open hours.
RIGHT: IBM Proprinter II and the arduino driving the printer directly via the parallel pinouts. BELOW: The pressure sensor hack made from two layers of aluminum mesh and one continuous layer of compressible anti-static foam. Compressing the foam decreases the resistance between its sides, making it an ideal candidate for a cheap and reliable voltage divider. |
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