
A tiny robot, often microscopic, designed to perform tasks at small scales such as in medical or manufacturing settings.Microrobots are miniature machines, typically ranging from a few micrometers to a few millimeters in size, engineered to operate at scales where conventional robots cannot. They are designed to perform precise tasks in confined or delicate environments, such as inside the human body for targeted drug delivery, in microfluidic chips for lab-on-a-chip diagnostics, or in manufacturing for micro-assembly. The field draws on principles from robotics, materials science, and micro-electromechanical systems (MEMS), and often involves wireless control via magnetic fields, light, or chemical reactions.
The concept emerged in the late 1980s with early MEMS devices, but the term 'microrobot' gained traction in the 1990s. Notable milestones include the first wirelessly controlled swimming microrobot in the early 2000s, developed by researchers like Bradley Nelson's group at ETH Zurich. However, the field is still evolving, and many foundational contributions are recent.
Microrobots are usually fabricated using photolithography or 3D printing at the microscale. Their locomotion depends on the environment: in fluids, they may use helical tails that rotate like corkscrews (mimicking bacteria) or rely on magnetic gradients to pull them along. In dry environments, they might walk or roll using tiny actuators. Power is often supplied externally—magnetic fields are common because they penetrate biological tissue harmlessly—or through onboard chemical reactions that generate propulsion. Control is achieved by modulating the external field or by designing the robot's shape to respond to specific stimuli.
Microrobots are being developed for targeted drug delivery, minimally invasive surgery (e.g., clearing blocked arteries), and environmental remediation, such as breaking down pollutants in water.
Some microrobots are inspired by sperm cells, using a single flagellum to swim through viscous fluids like cervical mucus.





