SpotMini, Boston Dynamics's dog-like quadruped robot, is back, and it's learned a new trick.

The robot, which was unveiled in June 2016 and then updated in November 2017, can now open doors and hold them open.

While opening a door is slightly old hat for a Boston Dynamics robot - Atlas barrelled through a push-bar door two years ago - SpotMini's operation is more fluid.

The robot uses its fifth appendage, an arm mounted essentially where a canine's head would be, to swiftly assess the door, locate and twist the handle, and pull the door open.

In a video released by Boston Dynamics, not only does the new-and-improved SpotMini open the door for itself, it even holds it open for its robot colleague.