Recently, a joint research team from the University of Pennsylvania and the University of Michigan announced the successful development of a fully programmable autonomous robot smaller than a grain of salt.
This micro-robot has not only set a new record for the smallest size of its kind, but also demonstrated enormous potential for mass production and application with an ultra-low manufacturing cost of approximately one US cent per unit. It is expected to be widely used in various fields such as healthcare and micro-manufacturing in the future.
Groundbreaking Development: Collaborative R&D Between Top Universities
The research and development work was completed through the division of labor and collaboration between the two universities, each leveraging their respective strengths. The School of Engineering at the University of Pennsylvania took charge of the physical structure and functional design of the micro-robot, while the team from the University of Michigan, drawing on its technical experience in creating the world’s smallest computer, equipped the robot with a “brain” that enables autonomous operation. In terms of size specifications, a single unit of this micro-robot has a volume of only 200×300×50 microns, which is comparable to the size of many microorganisms. Precisely because of its tiny size, it faces physical challenges completely different from those of conventional robots.
Part-Free Propulsion System: Overcoming Micro-Scale Physical Barriers
To address the drag and viscous effects at the micro-scale, the research team abandoned the traditional movement method of robots that rely on movable parts such as limbs, and designed an entirely new part-free propulsion system. The core principle of this system is that the robot generates an electric field on its own to drive the movement of ions in the surrounding solution, thereby propelling itself forward. Researchers can also adjust the ion electric field to achieve complex trajectory movements or coordinated operation of multiple robots. The part-free design also endows the robot with extremely high durability, ensuring that it will not be easily damaged even when subjected to external forces such as clamping.
Dual-Purpose Energy & Control: Innovations in Power Supply and “Brain” System
Energy supply is another major challenge in micro-robot R&D. The research team ultimately chose a solar cell as the energy carrier, which occupies a considerable portion of the robot’s volume. Although the team has maximized solar energy utilization efficiency, the output power of the battery is only 75 nanowatts, highlighting that improving energy efficiency will be a key direction for future research and development. In terms of the “brain” control system, the robot is equipped with a high-efficiency processor, memory, and sensors. Its command input is fully realized through light pulses, and the solar panel for energy supply thus achieves a “dual-purpose” function, fulfilling both energy conversion and signal reception. As for the data transmission link, the research team took an alternative approach: they enabled the robot to mimic the “waggle dance” of bees and transmit information through the movement posture of the propulsion system.
Mass Deployment Potential: Low-Cost & Long-Lifespan for Future Applications
It is worth mentioning that this micro-robot supports batch deployment for operations; hundreds of units can be deployed at one time to perform tasks collaboratively. Thanks to solar power supply and high-efficiency design, its autonomous operation lifespan can reach several months. Researchers emphasized that the low-cost feature of this fully programmable autonomous robot has laid a solid foundation for large-scale mass production. In the future, it is expected to play a pivotal role in more micro-scale scenarios such as targeted drug delivery in healthcare, precision operations in micro-manufacturing, and environmental monitoring at the micro-level, opening up new possibilities for technological innovation in multiple industries.
