Robotics X, the robotics research division of Chinese multinational conglomerate Tencent, has shown off a new robot dubbed Ollie — capable of performing the skateboarding trick which provided its name, by swinging around a wheeled "tail."
In a recently-published video, brought to our attention by IEEE Spectrum, Ollie is shown performing a range of tricks. The robot operates primarily on two wheels, located at the bottom of adjustable "legs," but it hides a secret: A third wheel, attached to an otherwise-hidden third limb, which it can deploy for a range of maneuvers including leaping into the air in an ollie and stretching as tall as possible.
The robot has been developed by Tencent's Robotics X division in partnership with scientists at New York University and the University of Manchester — but little is known about its operation. Thus far, the company has only published a single demonstration video with no description - and while a paper detailing its development has been submitted as part of the IEEE International Conference on Robotics and Automation 2021 (ICRA 2021) it has not yet been publicly released.
"This paper presents a balance control technique for a novel wheel-legged robot," the paper's abstract, penned by Shuai Wang and colleagues, reads. "We first derive a dynamic model of the robot and then apply linear output regulation along with the model-based linear quadratic regulator (LQR) to maintain the standing of the robot on the ground without moving backward and forward mightily."
"To take into account non-linearities in the model and obtain a large domain of stability, a non-linear controller based on the Interconnection and Damping Assignment - Passivity-based Control (IDA-PBC) method is exploited to control the robot in more general scenarios. Physical experiments are performed with various control tasks. Experimental results demonstrate that the linear output regulation can maintain the standing of the robot, and that non-linear controller can balance the robot under an initial starting angle far away from the equilibrium point, or under a changing robot height."
The paper, IEEE Spectrum's Evan Ackerman adds, "barely addresses the tail at all, except to say that currently the control system assumes that the tail is fixed" — suggesting additional development time between the submission of the paper back in October last year and the filming of the video showing off Ollie's semi-prehensile tail.
More information on the project is available on IEEE Spectrum.