Archive for October, 2010


Today marked the exciting transition between the preparation phase and the hermit crab data gathering phase of our CrabSense project.

When I got to our station on the floor, I checked the sensors that Melissa set up and attached them to the inside of the tank on the upper left side.  I checked the SD card in the DataLogger of the Arduino, and confirmed that we were getting CSV files containing reliable data from the sensors, along with date and time information.
CrabSense sensor and tank set-up
A big part of our data gathering is video and audio, which we decided not to do through the Arduino.  I checked out an AXIS 207W network camera and configured it to send me an email with an MPEG-4 video file whenever the camera detects any motion.  The sensitivity is set pretty high, to hopefully detect subtle movements.  The camera doesn’t really have a wide angle so it doesn’t capture as much of the tank as I’d hoped.  I attached it to a mic stand and set it up on the left edge of the tank, so that the Arduino could also rest on it.

Melissa wired up two small condenser microphones and attached them to quarter-inch plugs.  We checked out the Zoom audio recorder and after inserting a 16GB SD card, I configured it to record MP3 files at a variable bit rate (VBR) so that it doesn’t eat up space.  I  positioned the two mics on either side of the tank and connected them to the recorder on inputs 1 and 2.  I tested the recording and it is indeed producing a good sound file.  We’ll be importing it into a program like Audacity to look for peaks and changes in relation to time.

After getting the tech part out of the way, I then prepared the dirt substrate by soaking one of the dirt “bricks” that we got from PetCo in water, according to the instructions.  I went to PetCo and bought the remaining supplies, including sand substrate, and 3 hermit crabs with changes of shells (I chose crabs with natural shells, versus the painted shells — painted shells aren’t good for them because the paint can crack off and be ingested).  I felt and heard them moving around in their little box as I walked as quickly and steadily as I could back to ITP.  I kept telling them to “hang in there” — silly, I know, but I felt bad for them knowing it must have been so jarring to be exposed to so much movement and noise.

Once back at the station, I poured the bag of sand substrate into the left half of the tank and the moist dirt into the right side of the tank.  I took them out of the box — they were each hiding in their shells — and put them on the sand side, thinking they would like that better.  But within a few seconds of feeling the sand, they decided to move to the dirt side.  I captured their migration in a couple photos and video clips (see embedded video below).

CrabSense Project: hermit crab setup from Nisma Z on Vimeo.

After they huddled, they split up.  The one with the smooth round shell went to the right, front corner of the tank and stayed there.  The one with the cone shell positioned itself by the edge of the coconut house and the tank.  The adventurer with the spiral patterned shell wanted to be on top of the coconut house.  It peered behind the coconut fiber climbing wall and I was worried that it might go behind it, but it didn’t.  It tried to climb up the side of the tank but realized it couldn’t do that.  It eventually climbed down and onto the cone shell crab, who didn’t seem to mind.  Right before I left, I peered back in and didn’t see the adventurer – it must have burrowed into the dirt.

I was surprised that they seemed to prefer the edge by the window, which is colder.  I thought they would prefer heat and sand but apparently it’s the opposite.  I was worried about the heat though. When I was at PetCo, I purchased a 75 Watt bulb for nighttime viewing that also generates some heat and I set that up on top of the mic/tripod stand, so they should be okay for tonight.

I should have taken a photo of the whole tank set up with everything…I was in a rush to catch my train home…I’ll plan to take a photo first thing in the morning.  Aside from the sensors, two mics, and humidity and temperature monitors, the tank is now set up with the sand and dirt, a backdrop for climbing, a large natural climbing structure, a coconut house, four medium growth shells, one clam shell with eight pellets of food, one clam shell with regular water, and one bathing rock with salt water.  We intended to add plants, but we’ll either have to get a bigger tank or swap out the climbing structure with a smaller one to make room.

Play the Food Guessing Game first and then return to this post to read about it.  I look forward to your comments!

For this assignment, our instructors asked us to pick a topic we are passionate about and make a statement about it through a playable game or a self-explanatory art piece with game mechanics.  They also wanted us to make it in a medium that we’re comfortable with, to give them a sense of how we prefer to express ourselves.  The topic and medium came to mind right away: food and video.

People tend not to think too much about what they eat and why.  For me, thinking about the what and why of food, along with the short-term and long-term consequences, is a daily habit.  In a nutshell, I’m pretty dedicated to an organic, mostly vegan diet for a range of reasons that I won’t get into right now.  I originally wanted to make a game that encouraged people to eat healthier but I couldn’t come up with a way to do it that didn’t seem didactic.  So I decided to interview random strangers about their favorite food and make a game out of it.

I enjoy meeting people through video, getting them to talk about something they love – seeing their eyes light up, observing the transformation in their mood as fun memories surface in their mind, and leaving them in a happy state of being. I originally wanted people to describe food in an abstract or poetic way so that I could have the player guess between a food and something else, like an item of clothing, a place, etc.  But if food is described too abstractly (as in the beginning of the cheesecake example), then the player has no idea what the person is talking about.  I think the videos that I included in this piece strike a pretty good balance between making the player think and eventually giving them enough clues so they can guess the correct food.  (Note: I shot this pretty informally on a windy day, so it’s not quite up to my usual quality standards.)

The first version of the game showed the player the first part of the video and then displayed a message asking whether they wanted to guess or hear more of the video.  The player had to guess by typing in the name of the food, which would then prompt a display with the answer and give them a point if they got it right.  They would have to do that with each of the four videos.  I game-tested this with a couple people, who found it too hard to guess exactly what the food was or spell it properly (for instance, enchilada).  It also took longer to play than I had wanted because of the sequential nature of the video playing, and the experience of playing it in this way didn’t highlight all the things that I wanted the player to experience.  Plus this first version was built in Processing, which does a bad job of playing videos.

This version of the game is built in Flash, because Flash does a much better job of handling video clips and I wanted to learn Flash and ActionScript.  Craig Kapp, an ActionScript expert and collaborator on another project, taught me how to program this, and I’m proud to say that I figured out how to make the final confirmation screen on my own.  The game begins by asking the player to pick and drag their food choices for each person.  Game tester Sebastian is the one who had suggested this initial step when I explained that I wanted to play on people’s natural tendencies to stereotype others or size them up at first glance. I also thought it would be a quick and fun entrée to the game to have people think about what these four people love to eat based on just an image.  I noticed that game players actually talked through their logic for choosing foods for people, in order to justify their initial choices.  Only after the player fills each person’s box with food are they allowed to watch each person’s video to hear the food descriptions.   This phase of the game tests the player’s listening skills, patience and memory, because half of the food choices are blocked, and also provides a way for the player to “get to know” the person who was interviewed.  The player then gets the opportunity to guess again by dragging food choices.  This cycle continues until the player gets all four choices correct, which prompts a confirmation screen along with the names of the foods to supplement the food images.  There is more I could do to refine the game but I’m pleasantly satisfied with where I got it to today, and am thrilled with the positive feedback that it got.

I really enjoyed making this game.  From the people I interviewed, I realized from chatting with them after I videotaped them, how much their favorite foods remind them of home and are tied to childhood memories, and it made me think of foods that I loved as a kid but rarely eat now. Even though I advocate for healthy eating, I think there’s room for indulgences in these favorite foods once in awhile, especially because of the memories and comforting feelings they carry with them, and spacing them out makes them more special anyway.

My project partner, Melissa Clarke, and I are planning to create a vivarium (an enclosed or semi-enclosed container for plants and animals) as well as a sensor kit for monitoring changes in an interior environment before, during and after the vivarium is introduced into the space.  The sensors will also be used to monitor the biosphere of the vivarium.  We want to use sensors that monitor air quality, dust, temperature, and humidity. Check out Melissa’s blog for details on sensors and design drawings.

I was inspired to switch from a terrarium to a vivarium after observing leaf-cutting ants on display at the New York Hall of Science.  I was out there recently for the Maker Faire event and this display caught my attention because I observed adults who were totally entranced by the little ants carrying leaf bits that were at least four-times their size.  Watching the little creatures working so hard yet seemingly nonchalantly was fascinating.  I know, I’m anthropomorphizing the ants, I can’t help it.  I know others will do that as well, so introducing little creatures into a terrarium should dramatically increase complexity and interest and encourage other people to create their own vivariums.

I’m in the process of researching what creatures we should work with.  Crickets are an obvious choice, which reminds me of fellow ITP student Jill Haefele’s Living Headphones project.  I’m more intrigued though by hermit crabs and stick insects, both of which moult.

Hermit crabs are ironically social, so we’ll have to get a bunch.  They’ll also require water bowls and a temperature and humidity-controlled environment.  They love to climb, which makes me want to design little jungle gyms or other such structures to see if they’ll play with them.  Stick insects are among the best camouflaged of all creatures, so spotting them can be challenging but delightfully surprising.  They are mainly nocturnal, so we’d like to add a camera sensor to take snapshots at regular intervals when we’re not around.

The design idea that came into my head when I switched my thinking to a vivarium was a clear double-cylinder (like a large donut), with the inner diameter large enough for a person to insert their head and rotate 360 degrees at their leisure, to observe the creatures and plants in an immersive fashion.  The outer diameter of the cylinder would perhaps be 6 inches bigger, to form an enclosed environment, although the top of it could be a mesh to allow for air circulation.  I like Melissa’s organically-shaped interpretation, although for that creation we’d need a custom glass blower to make it for us.  My cylinder idea isn’t very practical either, so I’m sure we’ll modify our design.

We are planning next to visit some terrarium/vivarium shops around the city to get ideas for shapes, materials and plants.