Since time immemorial, robot developers have long looked at nature for inspiration. When designing robot mechanisms and movement, animals and human motor functions provide insight into the optimal movement that many robotic engineers had the curiosity to always try to replicate it.

In the past 25 years, a small design lab at Harvard has been relentlessly working on a unique robotics project perfecting the world’s first and only RoboBee. After many upgradations, now this Harvard’s tiny robotic bee has learned how to stick to surfaces like Spiderman. Unlike spiders that use thousands of tiny hairs to climb walls, though, the upgraded RoboBee uses the power of static electricity as a team of engineers from both Harvard and MIT wanted it to find a way for minuscule drone batteries to last longer.

Hybrid RoboBee

The concept of RoboBee was first conceived by mechanical engineering student Robert Wood in 1991, much before Hollywood grabbed the idea and showcased in its films. Since then, the RoboBee project has been constantly a perennial work-in-progress for scientists and students at the Harvard School of Engineering and Applied Sciences and the Wyss Institute for Biologically-Inspired Engineering.

In true sense, the RoboBee is a mechanical marvel. Be its tiny polymer wings which are designed to mimic real insect wings are powered by small ceramic muscles that convert electrical pulses into kinetic energy, making the RoboBee the world’s smallest flapping wing aircraft.  

RoboBee Features  & Facts

• The latest version of the RoboBee can stick to walls, can fly, dive into the water, swim around, and propel out of the water
• All those are tricky manoeuvres for RoboBee is based on larger amphibious drones that manage those tricks
• RoboBee weighs in at mere 175 milligrams only. The tiny machine overcomes forces of mass, volume, and surface tension that are completely different than what a bird-sized robot must deal with
• The bot also requires a multimodal locomotive system that enables it to fly and swim
• The RoboBee is nearly 1000 times lighter than any other aerial-aquatic robot, and this difference in scale is what’s kept decades worth of Harvard engineering students busy with the design
• The RoboBee represents a platform where the forces it experiences are different than what we at human scale do

Design, Structure & Functions Of RoboBee

1. The RoboBee has four buoyant outriggers specifically robotic floaties, essentially. To achieve lift-off from the surface into the air, the RoboBee uses a small electrolytic plate that converts water into oxyhydrogen, a combustible fuel.
2. It uses laser-cut materials that are layered and sandwiched together into a thin and flat plate. The flat materials then pop open like a book into its final and complete electromechanical structure.
3. Then the spark mechanism within the bot ignites the gas, powering the RoboBee upward like a minuscule rocket ship. Once the bot gets suspended in the air it then stabilises itself and lands.
4. The robots physical structure is inspired by the biology of a usual fly with only submillimetre-l scale anatomy and two wafer-thin wings. The wings are mostly are non-visible, flapping 120 times per second. It uses both motion control systems, as well as micro-manufacturing techniques.
5. The tiny robot uses piezoelectric actuators, which are made from strips of ceramic that expand and contract when an electric field is applied. Larger robots use electromagnetic motors but at this small scale, the piezoelectric actuators were the only alternative.
6. The carbon fibre body frame that it uses has thin plastic hinges that work as its joints. Then its balanced control system commands the rotational motions with each wing controlled independently in real-time.
7. The control system usually needs to react quickly but as powerful change takes place in airflow, which creates an outsized effect on the flight dynamics, the bot uses water to become buoyant and with an electrolytic plate in the chamber which then converts the water into oxyhydrogen.
8. This provides the robot with extra buoyancy needed for the wings to pop out of the water. This way the robot can fly into and an out of the water without any pertinent damage.

Applications Of RoboBee

• The RoboBee is used as a testbed for new robotic mechanical studies as well as new material construction methods. Recently, RoboBee even demonstrated a new programming language that taught the robots to not only move like the insect inspiration but also to think like them exactly mimicking the way an insect’s brain operates.

• Anyway, these flying microbots like RoboBee will play a highly beneficial role in agriculture, search and rescue missions, surveillance and climate monitoring. For example, the technologies developed to manufacture such Robobee could be used in the medical field to make small surgical devices for endoscopic procedures.
• Inspired by RoboBee functionality Ferrari’s labs also worked upon a new class of event-based sensing and control algorithms that mimic neural activity and also on swarms of RoboBee to make them communicate with one another and coordinate their movements.
• Ferrari’s lab teamed up with Harvard’s RoboBee to test the new chips. The robot has all the necessary vision, optical flow, and motion sensors needed to provide an adequate test bed.
• Ferrari lab is even installing RoboBee into newer microdevices such as a camera, expanded antennae for tactile feedback, contact sensors on the feet and air-flow sensors.
• Even many physics-based simulators models, follow  RoboBee and replicate its model with instantaneous aerodynamic forces that it would face during each wing stroke. This way the simulator can accurately model RoboBee’s motions during flights through complex environments.

Outlook

• One of the major drawbacks of RoboBee is that it has only remained a tethered device till now.
• RoboBee as a benchmark robot  is not a very difficult invention to build, but other robots that are already untethered would greatly benefit from this invention because they have similar  issues in terms of power
• Before any of these benefits can be realised, Harvard researchers must solve some tougher technical challenges to find how to power a small flying robot.