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Hello! This is the blog of Alexis Bates for the class Kinetic Sculpture with Arduino. Yes!

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YEAH IT WORKS!! YEAH!!!!!

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Segmented Wings by Dukno Yoon

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HERE IT IS HERE IS THE FINAL THING

I built this thing to put the lemons on. It is eighteen little pointy mounts, connected so that when the lemons (halves) are attached, they will be eighteen cells in series that leads around to a detachable LED.

Essentially, I winged it in deciding to make this setup over the three by three setup from the previous experiments. I attempted to test whether or not the size of the mounts had any effect on the functionality of the battery by comparing one orange slice with full-sized metal pieces versus two slices with half sized ones that were connected in series. The results were predictably that one was one battery and the other was two. ((It is only really dawning on me as I'm writing this that I could have compared one full-sized one with one half-sized one and that might have worked better.)) Anyway, I decided ((on the basis of bad information!!)) that experimenting was going to be pretty useless and that I should just go ahead and slice everything in half, so i did.

((The reason I did not attach the lemons yet/actually test this physical object is because I did not want to have to sand the mounts and risk it not working for class.))

The first thing I did was trace a lemon and an orange to find out what the diameters of them were. Eventually, though, in the interest of neatness and uniformity, I divided the board into a grid of four by five 3.75 inch squares with a 1 inch border.

Next, I found the approximate center of each square and drew two lines as a guide.

Using the drimmel, I gouged two little trenches in each square. These are to hold the mounts.

Here are the mounts, which were made of the same copper and zinc pieces from the experiment, only cut in half and with the oxidation gunk mostly sanded off and soldered to wires in pairs (as with the first set of mounts) so that the fruits will bridge the gaps between them. Here is the copper side of the mount...

...and here is the zinc side. I cut them into pointy shapes so that they would pierce the fruit more effectively and avoid me having to cut slits in them. After the mounts were assembled, I filled in the trenches with hot glue and stuck those suckers in there.

This is where the LED is attached. I soldered the end wires to alligator clips and clipped on a blue LED.

HERE'S THE WHOLE THING AW YEAH.

The biggest difficulty I had while assembling this was soldering to the mounts themselves, which was an exceedingly difficult process, owing to how the solder would not stick to the zinc pieces at all. While I eventually learned that the solder would stick to the copper if the copper were made hot enough, it would slide off the zinc like water off of anything no matter what. As a result, these connections are very delicate*, and as I was gluing the pieces in, many of them broke and required repairs.

*An ongoing problem that is still unresolved is this: one of the connections between wire and zinc is still not conductive, as in, it is soldered on there and stuck but the multimeter does not read it as conductive and I do not know why.

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THE WAY THE BATTERY WORKS IS THIS:

Two metal electrodes-- a positive cathode, like copper, and a negative anode, like zinc--are stuck inside of an electrically conductive solution, the electrolyte. This is a galvanic cell, which transfers chemical energy to electric energy.

Essentially, while the zinc anode is sitting pretty in the electrolyte, the electrolyte-- usually an acid, like citric acid found in citrus fruits or sulfuric acid as in car batteries-- dissolves the metallic zinc into positive ions, which leaves freed up negative electrons in the metal. This chemical reaction is called oxidation.

 (This also forms a thin layer of gunk-- like rust-- over the outside of the zinc. Because this protects/covers the electrodes and prevents them from coming into contact with the electrolyte, this also degrades the function of the battery cell over time.)

When the positive zinc ions enter the electrolyte, positive hydrogen ions from the electrolyte move toward the copper cathode. These combine with electrons from the copper to form hydrogen gas. This chemical reaction is called reduction.

As a battery, though, with a wire or circuit connected between the electrodes, the free electrons travel through the wire, exploiting their so-called "desire" to create hydrogen gas. This is the current flow that allows these cells to work electrically.

((This is correct as I understand it, though it was not without difficulty. I am sorry for any inaccuracies.))

sources: (x) (x)

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This is the plan for what I am going to try to build tomorrow! This plan is for nine little battery cells, but if my plan to split each copper piece in half does not work, then I will put in an empty cell and place the LED there instead of having it hang off the side. If my plan is successful, I will change the dimensions accordingly.

Essentially, the fruits will be laid out in halves, face down so as to obscure most of the metal pieces. The pieces will have wires soldered to them to connect in series, in a manner similar to the "football goal posts" from the previous rig. Because the LED will be connected with alligator clips, it will be possible to remove both the fruits and the LED if necessary.

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This is a video of the color change LED lighting up when connected to the array of orange slices. It is bright enough to be seen through the camera in the brightly lit room. Also, the red portion was lit up for a very long time. (I wonder if this is for the same reason that the red standalone LEDs tend to light up brighter?)

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These are the multimeter readings for the voltage, current, and resistance for each of the other setups. Some things to note:

The denominations of the measurements are not uniform, and this is because I chose whichever one best showed the measurement.

The current measurements are not the same as the ones from the initial test. These were taken later.

With the twisty wire, I had a hard time gathering up all of the galvanized pieces in the alligator clip, so these readings are perhaps not as accurate as they could be.

I think that these are interesting because even though they are the rejected attempts, you can still see the differences between the measurements and as a result, they can provide some tools to figure out why the other one was so much more successful.

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Here are the tests on the array that I made of orange quarters.

I cut up a bunch of oranges* into approximate quarters with a boxcutter and then stuck pieces of metal in them. Here is that. Each metal piece is about the same size, though I did not measure them precisely.

Then, I connected them in series. Some of the metal pieces were not as well planted and began to fall out. I am not sure if this had any effect on the final result.

This is the voltage coming off of one segment. (Pardon the minus sign!! I had it hooked up wrong!! Also pardon how all of these are in wildly different denominations of units, I just picked the one that showed the number best).

Here is the current. Please note that the currents listed in the previous test post were from a different test, done earlier, which is why they are different.

Here is the resistance. In this case, there was by far the least resistance as compared to the other tests. This is to be expected, and it furthers the idea that the amount of surface area contact would lessen resistance and/or raise the other items and made the LED work better.

Here is the blue LED as lit up by the orange array. It was bright enough to be seen well in the otherwise brightly lit room with the naked eye but not easily picked up by my phone camera.

Here is the red LED. I had a classmate cup her hands around it to take a better picture, but this was also bright enough to be seen in the same conditions as the blue one. Additionally, the red LED was brighter than the blue. This is unsurprising, as it takes less voltage to light up a red LED.

Because of the general success of this test-- the LED was lit up fairly brightly-- this has become the setup through which I will continue the project. Here are some things I am wondering about for future tests:

Will the LED become brighter + how much brighter when lemons are used instead of oranges?

Is the surface area of the metal pieces that sticks out of the oranges any help in lighting up the LED? That is, if I were to reduce the surface area out of the orange and/or increase that which is stuck in, would the LED work better?

Could I cut the pieces in half to create more individual slice cells and have the effect be the same and/or greater? This is linked to the previous question and also to how I have no more of that copper sheet to use.

My next step will be to work on answering those questions and to build a pretty rig to house this iteration of the battery.

*Fun fact! I cut up three total oranges-- two for the array and one for the metal tests from before, but when I was cleaning up, I only threw away two and a half oranges. Where did the others go?? Who the heck knows???

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This was the next stage in me attempting to increase the surface area contact between the fruit (the electrode) and the wires (the anode and the cathode). Here, I tried four different methods, each stuck in a segment of an orange, which I slices carefully with a boxcutter. The reason I used oranges instead of lemons is I was running out of lemons. In each of these, I tested the current that ran through the slice.

In this, I twisted together six pieces of copper wire and attempted to twist together six pieces of galvanized wire (but they were too thick, so i cut them up instead and stuck them close enough so they were all touching). This yielded the second most current, about 0.063mA.

Here, I just stuck in two wires, like I do. Unsurprisingly, considering the surface area consideration, this yielded the least current, about 0.021mA.

In this one, I used these things with the holes cut in them. We were not completely sure if the metal-colored one is galvanized or not. This came in at an unremarkable 0.024mA, even though it appears to have more surface area contact than the twisted wires. The reason for this could be the holes, which would reduce the surface area of the metal pieces. It also could be because we were not sure what the gray metal was made out of.

THIS ONE WAS THE BEST. It is a piece of a copper sheet and a piece of something that looks like it might have come off of a gutter or a sliding door (previously I was going to try to use a sheet of nails, but the nails were not continuous with each other because of the glue that held them together). It had by far the most current, at 0.92mA.

The one with the sheets was q u i t e  h e a r t e n i n g, to say the least. As a result, this was the one I continued to test with.

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Here are the first experiments that I did yesterday!

Trying to solve the mystery of how to get the LED to light up brightly-- now my sole purpose in life-- we figured that perhaps it was a matter of how much of the fruit was touching how much of the wire. Two ideas to maximize this surface area contact were putting two slices on each wire and threading the wire several times through each slice. These pictures are from testing the first idea. (I never tested the second one).

This is just the standard setup of five fruit pieces (in this photograph, oranges, though I also did one with lemons) on the stand. This lit up both the red and the blue LEDs very faintly-- basically what I expected it to do. Pictured here is the red LED glowing so little that you cannot see it in the photo.

These are the lemons doubled up on the wired, something I also did with oranges. In both case, the result was largely the same as it had been with the single slices.

Overall, this test did not really yield too much information, except that I might be doomed to fail*.

*I am writing this post from the perspective of someone actively doing the things pictured, like the talking head segments in reality shows, in order to preserve drama.

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Something strange happened and I do not know why-- the color change LED might have burned out?

The reason I think this is because I added two more lemons (in series) and now it doesn't go on at all. There is, of course, the possibility that I mucked up connecting the lemons but I do not think this is the case, as it was kind of fading before when there were only eight lemons in the same setup that made it work earlier. We measured the voltage and it came up with approximately 5 volts.

Then, we tested some other LEDs. The only one that worked was the blue one, pictured above. It was connected to the ten lemons in series and lit up quite brightly. Double threat professor/hand model Jason provides some shelter for the LED to better photograph the light.

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Here are some pictures from so far today.

So far, I tried to measure the voltage, current, and resistance for one, two, four etc lemon slices with the multimeter. This, however, did not work very well, as the measurements tended to jump around wildly or count steadily up or down. The reason for this is likely as follows: the multimeter uses a tiny tiny bit of electricity and because the amount of electricity generated from the lemons is so small, it affects the measurements (using voltage etc), which causes all of them to change, as they are mathematically connected. I think this is correct.

Then, instead of doing that, I plugged the LED into the battery. I used a color change LED, which fades between red, blue, and green. What happened was this: I gradually added lemon slices to the two rows, alternately checking to see if the LED worked with the rows connected in series and in parallel (the two series-rows in parallel with each other). The LED began to work with eight lemons, as shown in three (3), with only the red portion of the LED lighting up. This is to be expected, as a red LED uses the least voltage(?). This result was the same in both series and parallel. Four (4) is an attempt to take a picture of this, but the light was very faint and the room is too bright to show it.

Then, I added one more lemon to each row. When connected in series, as shown in five (5), all of the colors lit up with approximately the same degree of brightness. When connected in parallel, though, the only the red light lit up as much as it had previously, where the green lit up very, very faintly and the blue did not light up at all.

Some things not pictured include:

The moldy lemon slices from the last time I did this, which I forgot about for a week in the plastic bag with the un-peeled lemons. The mold was green-gray and white and powdery. Is it toxic? I sure hope not!!

[prostheticknowledge]

36 ventilators whirl 4.7m3 of packing chips

Latest installation from Zimoun uses simple materials to display turbulance - video embedded below:

From Creative Applications:

Opening this Saturday (April 26) at the Art Museum of Lugano in Switzerland, 36 ventilators, 4.7m³ packing chips is the new installation by Zimoun, the Bern-based artist known for his architecturally-minded platforms of sound. Zimoun yet again extends his installation inventory. Converting nine of the museum’s towering window spaces into ‘ventilation chambers’ (four ventilators are installed in each window) and filling them with polystyrene, Zimoun unleashes a perfect ‘plastic storm.’ Congregating into a mass that’s neither solid, gaseous nor liquid, the flakes perform a violent, otherworldy dance. With the phenonema trapped behind glass, we get to watch in wonder from the safety of the outside.

More at Creative Applications here Zimoun is also featured in Creative Application’s new magazine HOLO, which you can find out more here

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I would like to establish that while suggested uses for these batteries include calculators and digital watches, I want to build a tiny man puppet that is controlled by a tiny motor that is powered by these lemon batteries.

My inspiration for the tiny man is partially the Cottingley Fairy pictures (wow! weird!), but mostly tiny man Jesus:

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AT LONG LAST! THE LEMONS!

I bought fifteen lemons over the weekend. Here are some of them nestled comfortably in the bag.

And here are the peels after I went all Ramsay Bolton on them.

This is a set of twenty-five lemon slices arranged in five series-rows of five, with the rows then connected in parallel. (To connect them completely in series, I ran the alligator clips through the rows.)

And here are fifty slices arranged the same way except in five rows of ten. (I also completely disregarded the dividing line.)

After I took the lemons off, the wires had oxidized a little bit because of the chemical reaction that makes the battery work.In order to make the array work properly again, I have to sand down the wires a little bit.

Additionally, this time I took down how much voltage various configurations generated:

25 lemons, 5x5 parallel --> 3.17 volts

25 lemons, 25 series --> 7.38 volts

50 lemons, 5x10 parallel --> 5.70 volts

50 lemons, 50 series --> 7.23 volts

These are most likely not the most accurate numbers I could have come up with, though, as as soon as I touched the multimeter down, the voltage would begin to drop rapidly. This probably explains such discrepancies as the fifty series having less voltage than the twenty-five series.

This also prompted us to test the resistance of the array, which was tremendous. The array of fifty slices had around two million ohms of resistance!! This creates a problem because I guess it's really hard to power something with that kind of resistance, or something. (It is.)

Next time, perhaps I will attempt to do something like this. Though I am not sure where I will get a magnet core like that.

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...and here is my more serious solo attempt yet at building an array for these batteries. It consists of five rows of twelve "hurdles" stapled to a piece of wood.

First, I took a piece of copper wire and a piece of zinc (i guess) wire and bent them into this shape. Then, I taped them down gently and soldered them together.

I made sixty of these suckers!! Here is a little group shot.

Close-up of the board. The dotted line in the middle divides them into two groups of twenty-five. The lemons go in between the hurdles, speared on the right side by the copper and on the left side by the zinc.

Here is the finished thing!!