科学美国人60秒 SSS 敏感如蛇的热传感器

Heat Sensor 1 Has Snaky Sensitivity 敏感如蛇的热传感器

One of the most exquisite 2 heat sensors 3 in the world—it’s not in some government lab. It's in the head of a snake. The pit viper 4, to be specific.

世界上有一种最精敏的热传感器，它不存在于某个政府实验室里，而存在于一种蛇的脑袋里。这种蛇就是：颊窝毒蛇。

"They're incredibly sensitive. They beat any of the synthetic 5 counterparts, even the most expensive semiconducting systems used in infrared 7 or thermal 8 cameras today." Chiara Daraio, a materials scientist at Caltech. "They can effectively resolve a few millikelvin of temperature changes at a distance of up to a meter."

“它们非常敏感。它们击败了全部的人造传感器，甚至包括当今最贵的红外线或热像仪中使用的半导体系统。”加州理工学院的材料科学家基娅拉·达雷奥说，“它们能在一米远的距离外，有效分辨出几毫开氏的温度变化。”

Now Daraio and her colleagues have designed a heat-sensing material that competes with the sensitivity of the snake. Using pectin. Same stuff you used to thicken jam. “Pectin, a double-stranded molecule 9 ubiquitously present in the outer cell wall of plant cells, acts effectively as a tiny molecular 10 temperature sensor." When temperatures go up, she says, the double-stranded molecule unzips, "like the zipper 11 of a jacket."

达雷奥和同事们目前设计出了一种能与蛇的敏感度相媲美的热感应材料。他们使用的材料正是大家平时用来增稠果酱的材料——果胶。“果胶是植物细胞外细胞壁中无处不在的一种双链分子，它可作为一个微小的分子温度传感器有效地发挥作用。” 她称，当温度上升时，这种双链分子就会“像夹克上的拉链一样”解开。

So they did what you usually do with pectin—they made jelly, using pectin, water and calcium 12 ions. They dried that out, and got a thin, transparent 13 film. Then, they had to test it. Which they realized they could do using a microwave and her son’s teddy bear. "Which can be heated up to a temperature of 37 degrees, roughly the temperature of a mouse or a running prey 14 for a snake."

因而他们做了你平时用果胶做的事——用果胶、水和钙离子做了果冻。他们将其晒干，从而获得一个薄薄的透明薄膜。然后，再对其进行测试——用一个微波炉和达雷奥儿子的玩具泰迪熊。“它可以被加热至37度，即大致是可以被蛇捕食的一只小鼠或其它移动的猎物的温度。”

And the pectin film was exquisitely 15 sensitive to the warmed-up teddy bear—on par 6 with the snake. The film could detect temperature changes as small as 10-thousandths of a degree celsius 16. The study is in the journal Science Robotics.

结果，我们做的果胶薄膜对“泰迪熊”非常敏感，其敏感水平甚至等同于蛇的敏感度。这层薄膜能探测到小至万分之一摄氏度的温度变化。这项研究发表在《科学机器人》杂志上。

Daraio says the skin could give robots superior sensing abilities. "Allowing for example robots to determine whether they're moving around inanimate objects, other robots, or even humans or animals, which are evidently warmer bodies." Or, she says, it could be used in sensitive skin on prosthetic limbs for humans. If we can figure out how to connect this artificial skin up to something far more complicated. The brain.

达雷奥表示，这种皮肤能给机器人更灵敏的感知能力。“比如，它能帮机器人决定是否在无生命的物体、其他机器人、甚至是明显有体温的人类或动物的身边移动。” 或者，她说，它还可以被用到人类假肢上的敏感皮肤中。如果我们能找到办法将这种人造皮肤链接到更复杂的东西，比如大脑上。