Below is a short summary and detailed review of this video written by FutureFactual:
Insect-Sized Robotic Swarms: Robobees, Surface Tension and the Future of Micro-robotics
Veritasium’s tour of leading micro-robotics labs reveals how insect-sized robots fly and swim, overcome surface tension, and use innovative actuation such as piezoelectric crystals and soft polymer muscles. The video discusses practical applications in inspection and search‑and‑rescue, plus the challenges of autonomy, power, and ethical use. It culminates with a look at penny-sized combustion engines and the potential of swarms in dangerous environments.
Introduction to Micro-Robotics and Lab Frontiers
Derek Muller visits top micro-robotics labs to reveal a world where robots the size of bees can fly, swim, or hop. Researchers demonstrate a tiny yellow submarine that can both underwater dive and fly, and a 68 mg water‑walking crawler that interacts with surface tension in surprising ways. The work is driven by curiosity and potential real‑world impact, from disaster response to inspections in hard‑to-reach places.
"Bees can do much better jobs in terms of pollination than those robot, much more cheaply." - Dr. Kevin Chen
Why At Small Scales Flight Is So Demanding
At insect scale, high surface-area-to-volume ratios create strong drag and make soaring impractical. Insect‑sized flyers therefore rely on rapid wing flapping to generate lift via trailing‑edge vortices, a concept explained with reference to seeds that naturally generate lift through spinning and swirling air patterns. The video shows how these ideas translate into micro‑robots with flapping wings working in air or water, and why energy efficiency is a persistent constraint.
"When you shrink down to a smaller scale, your flapping frequency goes up higher, so we're at the 400 Hz range." - Dr. Kevin Chen
Piezoelectric vs Soft-Muscle Actuation
The early robobees used piezoelectric crystals to drive wings, which required a mechanical amplifier to achieve useful wing deflections. These crystals are fragile, so researchers at MIT are exploring soft polymer muscles coated with carbon nanotubes that act like tiny muscles, enabling higher flapping frequencies and better resilience. The polymer muscles can stretch up to about 25% of their length and are cycled hundreds of times per second to keep wings moving.
"the carbon nanotubes that are touching burn off, and so the muscle self heals" - Dr. Kevin Chen
Autonomy, Power and Self-Healing
To survive rough handling and potential damage, researchers designed self-healing mechanisms for the artificial muscles. Laser-assisted clearing and on-board self-repair allow the robots to keep flying after punctures. Despite these advances, energy density remains a limiting factor; batteries are heavy and inefficient at insect scale, so many designs rely on off‑board sensing, power and computation with a longer‑term goal of full autonomy.
"We have offboard sensing from those cameras. We have outboard power from those and offboard computation. What you see today is everything is off board, but hopefully in 5 years then we can combine both sensing autonomy and power autonomy." - Dr. Kevin Chen
Alternative Power: Micro Combustion and Jumping Drones
In a bold turn, researchers prototype penny‑sized combustion engines that burn methane and oxygen in tiny, controlled explosions to power micro‑flight. A flexible polymer membrane acts as a piston; heat is kept in check by the geometry of the combustion chamber, preventing backflow. With two small combustion chambers, the device can steer by activating opposing sides, delivering surprising power for its weight and enabling hopping flight to conserve energy.
"This robot is super powerful for its size. It weighs 1.6 g and can jump about 2 ft in the air. We can put a fuel tank, microelectronics, sensors, a camera, a battery, and still have weight left over to go, and this thing will still chug along." - Dr. Cameron Aubin
Applications, Ethics and the Path Forward
Micro-robots hold promise for search and rescue, disaster response, and engine-turbine inspection, yet concerns about privacy and misuse persist. Early deployments, such as post‑9/11 rubble searches, highlighted that scale and cost matter as much as capability. The researchers emphasize focusing on fundamental science, but acknowledge the need for safeguards and policy discussions to prevent harm as autonomy grows.
"If it's about application, we should all like make a startup and try to like think about what we can do to make money" - Dr. Kevin Chen