February 16, 2006
My Robot Can Kick Your Robot's ASCII
Nitinol - Muscle Wire: The Mauling
(sort of like muscle cars, except long and very skinny)
After World War II, the U.S Navy conducted research on alloys. Given the large amount of salt water to which ships are exposed, they were looking to create electronics on ships that were resistant to corrosion.
One of the alloys they came up with was a combination of roughly equal amounts of nickel and titanium, which they dubbed nitinol for NIckel TItanium Naval Office Laboratories.
Nitinol is one of a class of alloys called shape-memory alloys in that they return to their original shape after being deformed by bending or heating.
One use of shape memory alloys is in eyeglass frames. If you sit on them, they'll return to their propoer shape.
I had thought using nitinol would be a great way to get robots to get their lazy butts moving, but it turns out that nitinol only shines, so to speak, when it is inserted into a penis.
History
Sidebar |
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Nickel has a melting temperature of 1,453°C and titanium's melting point is 1,668°C (3,034°F).
So the fabrication of the alloy requires melting the two metals together at the higher temperature. For comparison, the surface of the Sun is around 5,800°K (~5,500°C, ~10000°F). The Greeks called the Sun Helios. The Romans called it Sol. There's a guy named Sol in Brooklyn. He sells fish. |
Nitinol is interesting to us, however, because of its reaction to changes in temperature. Normally, metals expand (slightly) when heated and contract (slightly) when cooled. That's why jar lids open more easily after running them under hot water. Nitinol however, shows the reverse property; shrinking when heated. Once cooled, it can be stretched back to its original length.
Since nitinol has some electrical resistance, simply running a current through it causes it to heat, and thus to shrink. This mimics the musculature of animals, which require an electrical signal to flex - hence the name 'muscle wire'.
Mark Tilden was an early advocate of using muscle wire in robotics, specifically those that rely on legs rather than on wheels.
Each manufacturer's brand of nitinol (Flexinol™ is a common one) is composed of a slightly different mixture (or admixture, if you will) of nickel and titanium. A common mixture is called 55-nitinol and is composed of 55% nickel and 45% titanium. Each type shrinks and expands at different temperatures, so you can select a type that actuates in a cold environment, such as on a satellite in outer space, or a warm environment such as the human body.
Unfortunately, the percentage of contraction is typically limited to between 4% and 8%, and the wire must cool before it is able to be stretched back into place and then heated and shrunk again. This means any robot that has its mobility dependent on muscle wire will likely move rather slowly compared to its motor-driven brethren.
Nitinol is not able to convert electricity into motion as well as motors can, but is much lighter than even a small motor and is appropriate for small, light-weight robots.
Many companies now fabricate nitinol for use in robotics and medical devices. The latter is probably the best venue for nitinol-based robotic devices, such as prosthetics, stents, shunts, or other small valves. Because it is non-corrosive, nitinol is an appropriate material to use within the human body.
Problems
One thing about muscle wires is that if you drop a piece, you're unlikely to find it. You're more likely to search on the floor and pick up one of Yan-yan's hairs, only to hook it up, put voltage to it and see smoke. Yan-yan's hairs do not make good actuators.
Penile Code |
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One use of nitinol is as a stent in penile implants, jokingly referred to as the "Autoboner".
Best when used with the AMS Sphincter 800™.
If you have the 650 or 700 series, you may want to upgrade. I wish I were kidding. More info here |
Another issue is that in every schematic I've seen the nitinol does double duty as actuator and current-bearing wire. The problem here is that they can't be insulated since the insulation would hinder their contraction and stretching. So we had to be very careful to not allow the exposed wires to touch any other metal contacts.
Problem #3 has to do with the extrememly specific power requirements of nitinol. It was easy to get a single wire to contract off of a 9V battery, but trying to power multiple wires did not result in less contraction, it resulted in zilch. Similarly, after we ran out of 0.1mm wire, we were unable to get any of the 0.05mm or 0.15mm wire to do anything. I couldn't tell how much the volatge mattered, but thinner wire can't tolerate much above 80 milliamps, and thicker wire needs at least 300. We tried putting 9V batteries in series and again in parallel in order to try higher voltages and currents but got nowhere. We may have toasted the 050 and not had enough for the 150. DC motors, those gentle souls, are so adaptive when it come to variability of current and voltage. But muscle wire is high-strung.
Which leads to p4: since the wire only has about 5% contraction, they must be taut to have any noticeable effect. Compounding that, they do not spring back when cooled unless a force acts on them to stretch them back to their original length. So we had to discover an entirely new art form of stringing nitinol wire to be under the precise tension to keep them taut at rest and under tension when flexed, yet not under so much tension that they are unable to perform. That sounds like a metephor for giving technical presentations.
The bottom line is that this tempered metal is temperamental (tempura-mental?) and although I imagine many future ITP students struggling in the exact same way we did, I don't think we'll be playing with it much.
Posted by mslaybau at 01:16 AM | Comments (0)
February 15, 2006
Synthetic Creatures
| Synthetic Creature | Material | Personality | Nature of Birth | Date |
|---|---|---|---|---|
| Talos | Bronze | Aggressive | Fashioned by Hephaestus | |
| Galatea (Pygmalion) | Stone | Not much | Aphrodite Intervention | "" |
| Golem | Clay | Creepy, vengful | Rabbis & God | 1579-ish |
| Gingerbread Man | Dough | Rascally, with hubris | ??? | ??? |
| Frankenstein's Monster | Dead people | Vengeful | Science | 1816 |
| Tin Man, Scarecrow | Straw, Tin | Kind | Witches | 1900 |
| Tik Tok | Metal | Stalwart | Witches again? | 1914 |
| Pinocchio | Wood | Impish | Fairy Intervention | 1914 |
| Marius, Sulla, Radius, Damon, et al. * | Metal | Hard-working | Science | 1921 |
| The Robot from Fritz Lang's Metropolis | Metal | Not much | Science | 1927 |
| Loads of B-Movie robots | Metal | Sometimes good, usually bad | Science | 1950s - 1960s |
| $6-million Man | Dead Steve Austin + 'Bionics' | Good guy | Science | 1974 |
| See-Threepio (C3PO) | Metal | Gay | Science | 1977 |
| Terminator | Metal | Jerk | Science | 1984 |
From these data we can conclude that creating synthetic creatures from organic materials result in more interesting personalities than we would get from inorganic ones.
Stone in particular yields sexy yet uninteresting girlfriends.
Synthetic creatures made from wood or plants tend to be spunky, while those made of rock or metal are true literalists, in that they adhere to Literalism.
Based on this theory, we can posit that an artificial man made of twine would be witty and urbane, at least in comparison to his metallic brethren.
We can also conclude that Science-generated creatures are in general scarier (or at least more powerful) than God-generated ones, especially when portrayed by Lee Majors.
Thirdly, female robots are boring.
It was really in the 20th century when the line between robotics and medicine began to blur, when it was possible to imagine a human being with mostly mechanical organs and limbs.
But, if you include Voodoo dolls in this list,
well then...
I'm not sure, but it's related.
* The first use of the word 'robot' is from this play: R.U.R. (ROSSUM'S UNIVERSAL ROBOTS)
Posted by mslaybau at 10:09 PM | Comments (0)
September 20, 2005
Mitsubishi Heavy Industries' New Robot
According to Mitsubishi, Wakamaru was designed by Mr. Toshiyuki Kita, who patterned the robot after a growing child. The name "wakamaru" derives from the childhood nickname of Minamoto Yoshitsune, a twelfth-century Japanese Samurai who engineered military victories that enabled his brother Yoritomo to gain control of Japan. The name is associated with "growth" and "development," the company says.
Wakamaru uses face recognition to identify up to ten people, including two that considers "owners." It uses speech recognition technology to identify 10,000 Japanese words. Speech synthesis capabilities include voice modulation and using gestures when speaking. It recognizes names given it by users, Mitsubishi says.
A panoramic top-of-head camera enables Wakamaru to identify its position in the house according to the ceiling. This camera also allows the robot to face others when speaking to them or being spoken to.
Wakamaru's claimed battery life is two hours, after which the robot returns to its charging station before power fails completely. It maintains Internet access and communications capabilities while charging, Mitsubishi says.
Posted by mslaybau at 02:47 PM | Comments (1)
October 26, 2004
Transistors
2N5087
PNP TO-92
Very Low current (max. 50 mA)
Low voltage (max. 50 V).
2N3906
PNP switching transistor in a TO-92; SOT54 plastic package. NPN complement: 2N3904.
* Low current (max. 200 mA)
* Low voltage (max. 40 V).
2N3904
NPN switching transistor in a TO-92; SOT54 plastic package. PNP complement: 2N3906.
* Low current (max. 200 mA)
* Low voltage (max. 40 V).
PN2222A; NPN switching transistor
NPN switching transistor in a TO-92; SOT54 plastic package. PNP complement: PN2907A.
* High current (max. 600 mA)
* Low voltage (max. 40 V).
2N2222A NPN General Purpose Transistor
NPN switching transistor in a TO-18 metal package. PNP complement: 2N2907A.
High current (max. 800 mA)
Low voltage (max. 40 V).
2N3055
NPN TO-3 metal case
Very High current (15 A)
Low Voltage (60 V)
Still Mysteries:
- 317T NLAS947
- 9451 N726
- N718 0289
- F852 895
Posted by mslaybau at 04:12 PM | Comments (0)
March 04, 2004
Robot Museum
The Robot Museum has been fallow for about two years, but is still worth seeing if you want to remind yourself of the aesthetics of toy robots in the '80s, pre-Terminator and pre-Aibo.
The guy on the right (trust, me, he's all man) is a Hong Kong ripoff of a stormtrooper from Star Wars, which weren't even robots anyway.
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Posted by mslaybau at 03:03 AM | Comments (0)
January 04, 2004
Robots in D&D Land
I like to analyze things, but just as the oyster needs a grain of sand around which to produce a pearl, I need some structure to focus my ramblings. There are also values for things like 'hit points' but that doesn't seem necessary to include here. Although, the issue of 'alignment' is interesting. D&D characters have, if I remember correctly, two values to indicate their moral stance: Lawful/Neutral/Chaotic and Good/Neutral/Evil.
When I was a kid I played Dungeons and Dragons. The game was okay, but the parts I enjoyed were coming up with characters and drawing maps.
Appropos of nothing, how would a robot do if it landed in D&D land?
Below is a chart that shows what would happen if a robot and I (as an exemplar human being) were placed in that world. The values are somewhere between averages and potentials for both humans and humanoid robots.
Human Robot Strength 11 16 Intelligence 12 5 Wisdom 12 3 Dexterity 9 3 Constitution 10 18 Charisma 10 5
So, the robot, if treated like a person or monster, would be the equivalent of some kind of brute, perhaps an autistic football player
Most people would be neutral-neutral, I suppose, but what about robots? Can they even have a sense of ethics, provided their wisdom is so low? On the one hand, they're not selfish, but they don't have a sense of the greater good either.
If we could actually make the proverbial 'evil robot' (I wish there were an actual proverb that had evil robots in it) then that would be cool.
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Posted by mslaybau at 06:38 AM | Comments (0)
December 27, 2003
Mesicopter
Read about the mesicopter, or look at images. It's a wee helicopter.
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Posted by mslaybau at 11:53 AM | Comments (0)
December 21, 2003
Robot Manager
Game idea: first-person perspective in 3D-environment. You and a few other people are on some planet - you're competing with them.
There are lots of resources, but you alone can't do much. However, there are loads of robots hanging around, and you can walk up to them and program them to gather wood or food or whatever. So, pretty soon, you can lie back and watch your minions serve you. But, you can also hunt down the other players' robots and either destroy them, or better yet, hack into them so that they carry the goods back to your house instead.
--------Posted by mslaybau at 11:19 AM | Comments (0)
December 20, 2003
Robolympics
After watching Beyond Human - Living Machines I have a prediction: Within 20 years we will see a robot olympics where countries such as the US, Japan, China, Japan, Germany, Japan, Italy, Japan, and India submit robotic teams to compete in traditional athletic events. We'll call it 'Robolympics', we'll get sponsors, sell TV broadcast rights, it'll be great.
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Posted by mslaybau at 02:15 AM | Comments (0)
December 19, 2003
Qrio
The latest humanoid robot (from Japan, of course) is named Qrio (pronounced 'queerio'? 'curio'?).
It's dancing isn't too good, and although the makers claim it can run, it runs as slowly as it walks, so no big advance there. It can through a ball pretty well, and that's amazing.
But - all of this kind of work is the same as the mechanical automata from a few hundred years ago in Germany and Switzerland - it's all mimicry and while it helps to understand movement, it doesn't seem to bring us any closer to a real intelligence.
Posted by mslaybau at 10:58 PM | Comments (0)