Researchers succeeded in building four-legged swarm robots | News | Notre-Dame news
As a robotics engineer, Yasemin Ozkan-Aydin, assistant professor of electrical engineering at the University of Notre Dame, draws inspiration from biological systems. The collective behaviors of ants, bees and birds to solve problems and overcome obstacles is something that researchers have developed in aerial and underwater robotics. However, the development of small-scale swarm robots capable of traversing complex terrain comes with a unique set of challenges.
In research published in Science Robotics, Ozkan-Aydin explains how she was able to build multi-legged robots capable of maneuvering in harsh environments and collectively accomplishing difficult tasks, mimicking their counterparts in the natural world.
“Legged robots can navigate difficult environments such as rough terrain and tight spaces, and the use of limbs provides effective body support, allows for quick maneuverability and makes it easier to overcome obstacles,” said Ozkan. -Aydin. “However, legged robots face unique mobility challenges in terrestrial environments, resulting in reduced locomotor performance.”
For the study, Ozkan-Aydin said, she hypothesized that a physical connection between individual robots could improve the mobility of a legged earth collective system. Individual robots performed simple or small tasks, such as moving on a smooth surface or carrying a light object, but if the task was beyond the capabilities of the single unit, the robots physically connected with each other to form a system. multi-legged larger and collectively overcome the problems.
“When ants are picking up or carrying objects, if an obstacle is encountered, the group works collectively to overcome that obstacle. If there’s a gap in the path, for example, they’ll form a bridge for other ants to cross – and that’s the inspiration for this study, ”she said. “Through robotics, we are able to better understand the collective dynamics and behaviors of these biological systems and explore how we might use this type of technology in the future. “
Using a 3D printer, Ozkan-Aydin built four-legged robots measuring 15 to 20 centimeters, or about 6 to 8 inches long. Each was fitted with a lithium-polymer battery, a microcontroller, and three sensors – a light sensor on the front and two magnetic touch sensors on the front and back, allowing robots to connect to each other. to each other. Four flexible feet reduced the need for additional sensors and parts and gave the robots a level of mechanical intelligence, which aided when interacting with rough or uneven terrain.
“You don’t need additional sensors to detect obstacles because the flexibility of the legs helps the robot to pass them,” said Ozkan-Aydin. “They can test the gaps in a path, building a bridge with their bodies; move objects individually; or connect to move objects collectively in different types of environments, similar to ants.
Ozkan-Aydin began research for the study in early 2020, when much of the country was shut down due to the COVID-19 pandemic. After printing each robot, she built each one and conducted her experiments at home, in her yard, or at the playground with her son. The robots were tested on grass, mulch, leaves and acorns. Flat ground experiments were carried out on particle board and she built stairs using foam insulation. The robots were also tested on high pile carpet, and rectangular wood blocks were glued to particle board to serve as rough terrain.
When an individual unit was stuck, a signal was sent to additional robots, which linked together to provide support in successfully traversing obstacles while working collectively.
Ozkan-Aydin says there are still improvements to be made to its design. But she waits the study results will inform the design of low-cost leg swarms that can adapt to unforeseen situations and perform real-world cooperative tasks such as search and rescue operations, mass transit d ‘objects, space exploration and environmental monitoring. His research will focus on improving the control, sensing and power capabilities of the system, which are essential for locomotion and problem solving in the real world. She plans to use this system to explore the collective dynamics of insects such as ants and termites.
“For functioning swarm systems, the battery technology needs to be improved,” she said. “We need small batteries that can deliver more power, ideally lasting longer than 10 hours. Otherwise, using this type of system in the real world is not sustainable. Additional limitations include the need for more sensors and more powerful motors, while keeping the size of the robots small.
“You have to think about how robots would work in the real world, so you have to think about how much power is required, what size of battery you are using. Everything is limited, so you have to make decisions with each part of the machine.
Daniel I. Goldman of the Georgia Institute of Technology is a co-author of the study.
Contact: Jessica Sieff, Deputy Director of Media Relations, 574-631-3933, [email protected]