Jie Qi at the High-Low Tech lab at MIT’s Media Lab, posted a HOWTO on nitinol and origami. In the HOWTO she mentions that you can’t solder the nitinol directly, and so you’ll have to have create a soldering pad for it. (She used a craft crimp bead.) Another tip she gives is the need to preheat the nitinol by running a 9 volt charge through it for five seconds. When the wire relaxes, it will become be longer than it was originally, and so you’ll need to retention the wire. Last of all, she warns against keeping the wire energized too long, lest your “burn out” the nitinol. In another project, Qi mentions she used 0.006 inch flexinol for the origami, but used 0.01 inch for the more rapid vine/snake project.
I have had a fairly long interest in synthetic plants and was thinking if nitinol could be used to in a heliostat or some sort of dinural deployable structure, but I never knew the reaction time of nitinol. Seeing it used understanding what voltages are required was helpful. (Poking around just now, I also ended up finding a handy nitinol wire width-voltage-time-force table.) While I doubt that I will ever actually build whatever vague idea idea I have for synthetic plant, I’ve come to conclusion that nitinol perhaps isn’t the best choice of materials if you want it to hold position for any considerable length of time (or at least not without some sort of mechanical latching).
The winner of this year’s James Dyson Award, Edward Linnacre’s Airdrop is a device that extracts water from air for use as in irrigation. If this sounds, like a Tatooine moisture farm, it should. However, unlike Uncle Owen’s GX-8 water vaporator, the Airdrop doesn’t use refrigerant, but rather the temperature differential from air to soil.
The Airdrop consists of a small reservoir buried about two meters in soil. Rising out of the tank and up to the surface is a cylinder containing a copper coil filled with copper ball bearings used in home distilleries. The copper tubing continues up to a turbine like those used on attic vents, but with the vanes turned around so that air is driven into the tubing instead of out of it. Also in cylinder is a submersible pump that transfers water from the tank to a drip irrigation line. The pump is controlled by an embedded microcontroller and solar powered. In times of little wind, the turbine can be powered by an electric motor.
d&@le Concepts concepts (nomme de art for Alessandro De Ambrogio and Carlos Basanta) have created the GUL Two, a solar powered LED plant that lights up at night. Currently installed at in the Elemental Gardens at Pacific National Exhibition in Vancouver.
Bashkim Isai has hooked up a plant so that it gets its nourishment from interacting a social networks. Named Meet Eater, the plant receives a dose of water every time someone performs a social gesture about it on Facebook. After 91 days, it currently has 8140 fans.
Do we have something to replace Internet vending machines? No. Nothing will replace Internet vending machines.
MIT has published a paper entitled Programmable Matter by Folding (full article) that describes paper that can fold itself into a variety of shapes. The paper is covered by is divided into triangular sections that are joined by a network of thin nitinol actuators that contract under voltage. At the center of each section is a magnet that is used to retain the paper’s shape.
While I’m sure MIT had bigger plans for this tech (Well if it was the Media Lab, perhaps not.), I immediately thought that this was the perfect thing for synthetic plants. I’ve been thinking about how nitinol wires, or at least something like them, could deform a paper but thought that the being able to compresses only about 4% was a problem. When I first saw this video, I thought they were using something else besides nitinol, but they’re not. The trick they they used to get 180 degree bending is folding and annealing the 100μm foil so that the nitinol will remember the folded shape. Once it cooled, the foil is manually flattened, and then reheating the foil with electrical current will cause it return to the folded shape.
Ah, Vivien Muller! Is there anything you make that I won’t post? Above is Electree, his latest creation. It’s a purple Photonsynthese, and is being presented at the Palais de Tokyo in Paris on the occasion of the 1.618 sustainable luxury fair.
Limited to 1000 editions. Price €4950 (~ $6354).
I like it. I like the blue of Photonsynthese more though. Don’t like the price at all. More disturbingly, it’s just too derivative of his earlier work. It seems like the big change in this one is that it uses rare earth magnets instead of headphone jacks to mount the solar cells. Really, really don’t like that price.
We Make Money, Not Art interviews, Gilberto Esparza about his Plantas Nómadas (Nomadic Plants), an autonomous walking robot that is powered by a combination of solar cells and a microbial fuel cell. When the fuel cell output drops beneath some threshold, the bot seeks out a water source, extends a proboscis and refills the fuel cell. Additional water is used nourish a colony of on board plants.
Gilberto’s earlier work is equally interesting. Parasitos Urbanos (Urban Parasites) (flashless site) was a series of robots inductively powered from electrical transmission lines that would move through the urban environment mimicking sounds they encounter.
Spanish art collective, Luzinterruptus latest creation, Jardín para un Futuro, No Muy Lejano (Garden for a Not Too Distant Future), is 110 clear plastic containers, each containing a few leaves and branches, along with a green LED.
The artist statement says that installation was a humorous statement about the lack of green space in modern cities; but given the frequency of their installations, I think that’s more just talk than anything.
This past weekend, Ming and I planted a couple of tomato plants in pots to grow. As part of the fun, we’re keeping a log of how fast the plants grow. Doing this has given me flashbacks to LDEFSEEDS experiment which involved both school children and “real” scientists growing tomatoes that were exposed to the radiation of space for almost six years. (FYI: Space seeds had higher germination rates, but tasted the same as Earth tomatoes.)
While thinking about plant growth rates, I came across Natural Selection by Tom Simpson of Studio Lithero. It is perhaps the most boring death race ever. (Actually, it’s pretty cool sped up.) Three plants enter. One plant leaves (HA!), and becomes president. Sensors at the top of the stand trigger cutters at the bottom.
I’ve been thinking more about solar plants recently. I like how these projects combine both form and function. I’ve been thinking about what I’d like in one of these, and how one would be made. First, the power being collected by the solar cells needs to go somewhere. It could just feed back into the device, which is exactly what happens with plants, but part of me likes the idea of having the sculpture(?) have a practical use as well. If I want practicality, then USB ports for charging an iPod or a phone that I don’t have would be nice. At least one port, but four would be more than plenty. I’m leaning towards the solar cells charging some li-ion or nicad battery coupled with something like a Minty Boost.
The second feature I’ve been hammering the previous electronic plants I’ve looked at is the movement, specifically heliotropism (i.e. sun tracking). It’s an interesting feature, and it would increase the power to the photovoltaics. I don’t like the idea of the hearing servos move, so that means nitinol wires, which also have the quality of more closely resembling natural motion by simply expanding and contracting. The next question then becomes, what form would the motion would take?
If rigid photovoltaics are used, then panel could be mounted to a universal joint with the two outside corners independently controlled by nitinol. The other idea is to use flexible photovoltaics and hopefully no hinges and joints.
Another interesting idea is to think about deployable structures, which would seem to imply the use of flexible photovoltaics. It’s not exactly the heliotropism I was thinking of, but it would be cool if the “leaves” opened up in the day, tracked the light, and then closed at night.
Doing all of this nitinol might be kind of difficult. Heating nitinol causes it to contract in the 3 – 5 % range, doesn’t seem like much. This also means that for a deployable structure, it needs to collapse when the wires are extended,
Will I actually build this? Probably not, but it is something I’ve been thinking about. Perhaps it would give me an excuse to visit Noisebridge.