Tuesday, February 23, 2010



pHloat is a DIY kit that is made for use in conjunction with a pre-owned / pre-existing arduino microcontroller. Its purpose is to test the pH levels in local rivers, lakes, and streams due to the influx of air and water pollution often caused by acid rain. It is specifically designed to be used in areas that are home to refineries, chemical plants, and manufacturing industries that are causing environmental damage. However, it can be used in any body of water to test acidity levels.

pHloat has the option to be made from several recycled materials including but not limited to, plastic water bottles, scrap wood, aluminum containers, rope, and paper. If these materials cannot be found they can be purchased along with the necessary electrical components for approximately $25. pHloat functions through the modification of a simple garden moisture and pH sensor that can be purchased at any home improvement store. It acts as both an environmental measurement tool and a floating sculpture, borrowing inspiration from Japanese floating paper lanterns and a DIY buoy design found on instructables.com. As the pHloat navigates down a stream it is taking a constant pH reading that is being translated by the arduino to produce a variation of colored light (produced by a low energy and cost superbright RGB LED). The different colors of light indicate the level of acidity in the body of water. For example, a normal pH reading would result in the emission of green light while a high pH reading would result in the emission of blue light. The light is housed on the top of the pHloat and is illuminated under a paper origami shade. As to not further contribute to environmental pollution, a rope (not pictured in the 3d models) should be attached to each pHloat so it can easily be retrieved from the water (this allows for the pHloats to also be affixed to a particular area measuring passing water).

pHloat is designed to create a social awareness of pollution in local rivers, streams, and lakes. It also functions as visual expression of concern for the emission of dangerous chemicals into our atmosphere. pHloats are designed to be released together to ultimately create floating mobile sculptures. Thus initiating a social space that engages locals living in the midst of these manufacturing industries to begin a dialogue about their environmental conditions.

I personally intend to create several of these to test the waters in my hometown of Lima, Ohio. Lima is home to a multitude of manufacturing plants including, Husky Oil Refinery, Procter & Gamble, The Lima Tank Plant, Ford Engine Plant, The Dana Corporation, and Superior metal. All of which emit some form of pollution (though not admittedly) into the local environment. The largest local park, where many of the track and cross-country teams practice, is also located adjacent to the oil refinery and the air quality is often unbearable. Though the concern for acid rain pollution has somewhat diminished, I am interested in finding out if it is still a viable problem in areas that have a high level of toxic waste emission.

EPA Information about Acid Rain: http://www.epa.gov/acidrain/index.html

Design inspiration from Buoy Instructable: http://www.instructables.com/id/BUOY/


Leads of pH sensor

pHloat with origami shade

Example Shade

Example Shade

Due 3/2/10 at 5pm: 5 Scanned Fabrication Plans

Materials List and Partial Fabrication Plans PDF (click to open)

Due 3/10/10 Phase 1: Constructions

First completed pHloat

First completed pHloat. Rope to be attached to weight (rock) so it stays in place in water.

Detail of the top and circuit board.

Side view with pH sensor

Temporary shade / protection attachment

Green for save pH level

Blue for higher than normal pH level

Red for very high pH levels.

Beginning phase of kit construction. Plastic bottles are to be found/recycled and are not included. Enclosure made from recycled cardboard.

Arduino Code:

int LED = 13;//output pin is #13 for normal acidity level
int LED1 = 12;//output pin is #12 for middle acidity level
int LED2 = 8;//output pin is #8 for high acidity level
int sensorValue = 0;//"place" to store the incoming analog values to be read
int sensor = 1;//sensor input attached pin #1

void setup() {
pinMode(LED1, OUTPUT);
pinMode(LED2, OUTPUT);
pinMode(sensor, INPUT);//you don't have to declare "INPUT" since arduino seta all pins as input. I do it for remembering...
Serial.begin(9600);//get ready for serial communication

void loop() {
sensorValue =analogRead(sensor);//read the sensor and put the value in the sensorValue "place"
Serial.println(sensorValue);//pint out on the serial monitor...
if(sensorValue >= 15)//should turn on the red LED because the pH sensor reading is greater than or equal to 15 meaning that the acidity level is dangerously high.
digitalWrite(LED2, HIGH);//turn on the red LED
digitalWrite(8,LOW);//should turn on the red LED because the pH sensor reading is greater than or equal to 15 meaning that the acidity level is dangerously high.
if(sensorValue >= 4 && sensorValue <=14)//should turn on the blue LED because the pH sensor reading is greater than or equal to 4 and less than or equal to 14 meaning that the acidity level is dangerously high.
digitalWrite(LED1, HIGH);//turn on the blue LED
digitalWrite(12,LOW);//should turn on the blue LED because the pH sensor reading is greater than or equal to 4 or less than or equal to 14 meaning that the acidity level is higher than normal.

if(sensorValue <= 3)//should turn on the green LED because the pH sensor reading is less than or equal to 3 meaning that the acidity level is normal.
digitalWrite(LED, HIGH);//turn on the green LED
digitalWrite(13,LOW);//the green LED will continuously stay on because it includes the value of 0 (less than or equal to 3)



  1. This comment has been removed by the author.

  2. This project seems very refined technically but is lacking in emotion.

    You have all the components necessary for success if you can explore why we should care about pH levels. We are bombarded daily with facts and figures about environmental degradation and human impact on various ecosystems, but finding an emotional thread that bridges the gap between objective, empirical fact and subjective, personal experience would be key to making this more than just a mere tool.

    You briefly link this project to the Japanese practice of Tōrō nagashi, the ceremony of placing floating paper lanterns in water to guide spirits (of dead folks) back to the other world. Exploring that practice a bit could help flesh out the human potential this project has.


    (do yourself a favor and mute the sound)

  3. I like this idea because it is visually interesting. The fact that you source recyclables is great: interesting use of materials, especialy paired with the origami. I would look to add some other layers of metaphor that would be pertinent. For example you cite site-specificity as one of your goals. What metaphor can you link there: Ohio: Ohio river:American Bottom? or River as transportation network? Maybe the implied duality is the Cloud-Rain-Runoff-River circuit versus the Water-Ph-Arduino-Light circuit. Or for something completely different, what if these pHloats came flying out of a UFO? What sense of urgency would that create compared with UFO sightings in the area?

    see also my Mermaids of the Chicago River


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