A team of researchers at the Singapore University of Technology and Design has unveiled a groundbreaking hybrid drone that revolutionizes the navigation of complex environments.
In a paper published in The International Journal of Robotics Research, researchers introduced the Aerial and Terrestrial mode Operating Mono-wing, or “ATOM,” a hybrid drone that, despite relying on just two actuators, effortlessly transitions between flying through the air and rolling across the ground.
“The robot is capable of vertical takeoff and landing in mono-wing flight mode, with the unique ability to fly in both clockwise and counterclockwise directions, setting it apart from traditional monowings,” researchers write. “The robot seamlessly transitions to ground locomotion mode, utilizing its frame to facilitate rolling motion on the ground.”
At first glance, ATOM resembles a skeletal drum, with a single, half-pear-shaped wing enclosed within its lightweight frame. This unique design, inspired by the winged Samara seed of trees like maples and ashes, sets ATOM apart in the world of drones. The Samara seed spins as it falls, using its tapered, aerodynamic shape to travel farther on the wind.
By emulating the natural design of the Samara seed, ATOM’s creators set out to improve lift, enhance stability, and most importantly, reduce energy consumption during flight. This energy efficiency is a key advantage of the hybrid drone, a sharp contrast to conventional aerial drones like quadcopters, which burn through significant energy to remain airborne.
While in flight, its mono-wing spins, powered by two counter-rotating motors that provide stability and control, allowing it to hover, ascend, or descend. The drone is capable of vertical takeoff and landing, a critical capability for navigating tight spaces or rugged landscapes where traditional drones might struggle.
The ATOM can also effortlessly transition from air to ground. ATOM achieves this shift with streamlined simplicity, unlike many hybrid robots, which rely on extra actuators that add weight and complexity or suffer from energy inefficiency during mode changes.
The ATOM achieves this by using a clever rolling frame that lets it glide across the ground like a wheel, using the same motors that power its flight. This minimalistic design reduces energy consumption and also enhances the robot’s durability.
“Typically, if a drone lands upside down due to an error, it would be unable to correct itself,” researchers note. “However, the unique design of ATOM ensures that it does not have an unrecoverable state.”
Developers described the ATOM as being “collision-tolerant,” both in flight and ground-mode operations, making it suited for operating in unpredictable environments.
The hybrid drone’s carbon-fiber-reinforced frame acts as both a protective cage during flight and the structure that enables its rolling locomotion on land. This design makes ATOM remarkably resilient and capable of handling bumps, scrapes, and uneven terrain while maintaining its operational integrity.
During testing, researchers demonstrated that the ATOM can navigate inclined surfaces up to 15 degrees, switch between flight and ground modes with near-perfect success rates, and conserve power in ways that traditional drones can’t match.
For example, in ground mode, ATOM could travel for nearly 45 minutes on a single small battery charge. In flight mode, the hybrid had an average range of nearly 5 minutes. This energy efficiency opens up possibilities for long-duration surveillance or search-and-rescue missions, where the robot could cover large distances on land and only take to the air when necessary.
ATOM can fly in both clockwise and counterclockwise directions—thanks to its twin-motor setup, which expands the hybrid drone’s versatility. These motors can deliver differential thrust during ground operation, allowing precise control over turns and direction.
The robot executes tight turns easily when rolling on smooth surfaces like vinyl flooring. However, rougher terrain presents challenges that researchers are working to address through further refinement.
Additionally, researchers noted that ATOM’s propellers are optimized for generating thrust in one direction, making the current design ideal for long-range ground travel with minimal stops or sharp turns.
The development of ATOM is driven by a growing demand for hybrid drones that can handle complex environments without relying on multiple specialized machines.
Potential applications for ATOM include disaster response, where rubble or collapsed structures might block conventional vehicles, and environmental monitoring in areas where both aerial and ground access are needed. In military or security contexts, its ability to switch modes could allow it to conduct reconnaissance while conserving power for critical moments.
That said, the ATOM prototype has some limitations. The hybrid drone’s ground speed tops out at around 5 mph. However, in certain situations, the tradeoff for speed could be acceptable, given the drone’s dual capabilities and energy savings.
Sharp turns at high speed also remain tricky, with the ATOM preferring to stop before reorienting. However, researchers point out that the drone can still perform large-radius turns while rolling, avoiding unnecessary stops that would sap efficiency.
Perhaps the most promising aspect of ATOM’s design is its simplicity. While many hybrid robots rely on complex transformation mechanisms or multiple motors to switch modes, ATOM achieves this with just two actuators and a smartly engineered frame.
This minimalist approach reduces mechanical failure points and could also help lower production costs, making the technology more accessible for widespread use.
The researchers are already exploring ways to improve ATOM’s performance on rough terrain and optimize its energy consumption during mode transitions.
Future iterations could see enhanced sensors or AI-driven autonomy to let ATOM navigate even more challenging environments without human guidance.
“Flights demonstrate that ATOM has no unrecoverable states, highlighting its resilience as a hybrid robot,” researchers write. “As part of our future research, we are exploring the development of a crawling mode for terrestrial locomotion. This mode would allow the robot to move by dragging its body, offering an alternative locomotion method in addition to rolling.”
Tim McMillan is a retired law enforcement executive, investigative reporter and co-founder of The Debrief. His writing typically focuses on defense, national security, the Intelligence Community and topics related to psychology. You can follow Tim on Twitter: @LtTimMcMillan. Tim can be reached by email: tim@thedebrief.org or through encrypted email: LtTimMcMillan@protonmail.com