It’s small, very small. How small? Fifty times smaller than half a millimeter. Northwestern University (USA) developed the microscopic crab robot. It is capable of walking on the edge of a coin. It is the smallest walking robot in history.
Science Robotics’ magazine tells its story. What uses would it have? From surgical procedures to repairing machinery in spaces where a wrench won’t fit.
“Our technology allows for a variety of controlled movement modalities. It walks with a speed of half the length of your body per second,” says Yonggang Huang. He is a mechanical engineer and part of the project.
The robot’s parts are attached to a stretched rubber substrate. When the material relaxes, the device acquires its shape. The shape of the robot can be precisely controlled. A similar approach is used with the moving parts, made of an alloy material.
Lasers act as a remote control. They are used to heat specific parts of the robot. As those parts transform into a different shape, they propel the crab forward. No power supply or motor is needed.
“Because these structures are so small, the cooling rate is very fast,” notes John Rogers. He is a materials scientist at the university. “Reducing the size of these robots allows them to run faster.” By adjusting the frequency of the laser scanning, the speed at which the robot moves can be modified.
The researchers say there is a lot of potential in their new process. They can make robots turn and jump using the same techniques, for example. As long as the robot is within line of sight of the laser, it can be manipulated remotely.
“Robotics is an exciting field of research. The development of microscale robots is a fun topic for academic exploration,” Rogers says. Yes, the microscopic crab robot is fun, but it’s also a technological breakthrough.