Designing agile robots to navigate through tight spaces in disaster zones or pipelines has proven challenging until now. Researchers at the Beijing Institute of Technology developed SQuRo (small-sized Quadruped Robotic Rat), a rat-inspired robot that possesses the ability to climb over objects, walk, and crawl. Even better, the robot also has fall-recovering capabilities, similar to an actual rat.
First, the team referred to rats’ X-Rays to better understand their anatomy. Afterward, they designed SQuRO to feature similar qualities to a real rat, including movement patterns, degrees of freedom (DOF), and structure. The waist, head, and limbs have two DOFs, allowing the robot to mimic a real rat’s flexible spine movement.
SQuRo then underwent varying experiments. The first one involved testing its crouching-to-standing, walking, turning, and crawling capabilities. It exhibited impressive turning results, where it turned on an extremely tight radius of less than half its body length. “Notably, the turning radius is much smaller than other robots, which guarantees the agile movement in narrow space,” says Qing Shi, a professor at the Beijing Institute of Technology. Afterward, the team put the robot through tougher tests. In one scenario, SQuRo successfully traveled through a narrow-irregular cave-like passage. Then, the robotic rat toted a 200-gram weight across a field with 20-degree inclines.
Robots that navigate through pipelines, disaster zones, or other demanding environments must climb over any obstacles blocking their path. So the team also designed SQuRo to lean back on its haunches and put its forelimbs into position to climb over an object. In their experiment, SQuRo demonstrates the ability to climb over 30 mm obstacles with a 70% success rate. The robot showed that it recovers after falling on its side in the final experiment.
“To the best of our knowledge, SQuRo is the first small-sized quadruped robot of this scale that is capable of performing five motion modes, which include crouching-to-standing, walking, crawling, turning, and fall recovery,” says Shi. The team’s next goal is to commercialize the robot and enhance its agility through closed-loop control and in-depth dynamic analysis. “Moreover, we will install more sensors on the robot to conduct field tests in narrow unstructured pipelines. We are confident that SQuRo has the potential to be used in pipeline [fault] detection after being equipped with cameras and other detection sensors.”
The real question, when can we have something like this as a home pet?