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Day of the Robotic Tentacle
holy_calamity writes "New Scientist is reporting on a robotic tentacle developed thanks to funding from military agency DARPA. From the video it looks to have a lot of potential, I can almost feel it fastening around my ankle right now."
Actually, when I was back in college, genetic algorithms were the hot topic in one of our VLSI classes that year. What they did was apply the genetic algorthim process to a Field Programmable Gate Array (FPGA) chip to solve a computation. An FPGA is sort of like a giant array of ANDs, ORs, and NOTs with a "control array" of flip-flops that allow you to control the routing of the inputs; you can just load in a new sequence and end up with different outputs using the same hardware. The genetic algorithm comes in by randomly generating the control array sequence. You then compare the output with the target output, then blend the successful solutions together until you have the final solution, all without any hardware design involved.
The story goes, some researchers did this to attempt to reproduce a non-linear equation, I think like a Fourier Transform. The plus side was, they were successfully able to demonstrate that the resultant chip configuration was able to provide the expected results. However, after analyzing the actually solution, the researchers found that the chip was actually creating resonance between different parts of the circuit in such a way that there was no direct path between the input and output signal.
The genetic algorithm had created an analog solution in digital hardware by incorporating the electromagnetic losses and field coupling of the FPGA wiring itself; if they had tried to tweak the "solution" by removing portions of the unused pieces of the FPGA circuit, or even using the same control sequence on a different FPGA, the "solution" would not work.
Lechery, sir, it provokes, and unprovokes;
it provokes the desire, but it takes
away the performance: therefore, much drink
may be said to be an equivocator with lechery:
it makes him, and it mars him; it sets
him on, and it takes him off; it persuades him,
and disheartens him; makes him stand to, and
not stand to; in conclusion, equivocates him
in a sleep, and, giving him the lie, leaves him.