A troop of a million walking robots could enable scientific exploration at a microscopic level.
Researchers have developed microscopic robots before, but they weren't able to move by themselves, says Marc Miskin at the University of Pennsylvania. That is partly because of a lack of micrometre-scale actuators（微米级致动器）---components required for movement, such as the bending of a robot's legs.
Miskin and his colleagues overcame this by developing a new type of actuator made of an extremely thin layer of platinum, a very valuable silvery-grey metal. Each robot uses four of these tiny actuators as legs, connected to solar cells on its back that can make the legs bend in response to laser light（激光）and push their square metallic bodies forwards.
“Each solar cell is connected to a specific leg and by shooting the solar cells with a laser, you make the legs move in the way you want,“ says Miskin. "It's really cool.”
Through a process similar to that used in creating circuit（电路）boards, Miskin and his team were able to mass-produce more than a million of the microrobots, each of which could only be seen under a microscope.
The robots are only able to walk around, but Miskin says they provide important evidence of concept, showing that it is possible to develop and mass-produce microrobots with on-board electronics. The next step will be to put additional functions together, he says. "We're developing things where we'll have sensing capabilities and well have programmability.”
He also wants to develop microrobot groups that work together. “There's all sorts of cool stuff that happens when you wind up with a lot of robots working together,“ he says.
In the future, these robots could let us explore the world at a microscopic scale. They could potentially be developed to wander inside the human body. "The hope is that these robots are really going to take us into the micro-world," says Miskin.
【小题1】What is the problem with previous microscopic robots?| A．Their lack of adjustable metal legs. | B．Their wrong way of walking alone. |
| C．Their insensitivity to tiny actuators. | D．Their inability to move automatically. |
| A．Solar cells. | B．Circuit boards. |
| C．A normal metal. | D．Natural sunlight. |
| A．To train an army made of microscopic robots. |
| B．To replace human employees with microscopic robots. |
| C．To change present microscopic robots into smaller ones. |
| D．To mass produce walking microscopic robots with on-board electronics. |
| A．Robots Are Exploring the Micro-world |
| B．An Army of Tiny Robots Are in Concept |
| C．Walking Microscopic Robots Are Created |
| D．Robots Will Walk Inside the Human Body |
