Japanese internet, solar and technology company SoftBank Group Corp. is buying robotics pioneer Boston Dynamics from Alphabet Inc., Google's parent.

Terms of the deal, announced Friday, were not disclosed.

SoftBank, which offers the Pepper companion robot, said the purchase underlines how robotics is a key part of its business.

Boston Dynamics makes various robots, including Big Dog and Spot, complex machines that walk and trot on four legs, as well as Atlas, which walks on two legs like a human. Atlas has arms and can open doors and lift items.

Under Friday's deal, SoftBank is also buying from Alphabet a company called Schaft that develops humanoids and came out of the University of Tokyo.

SoftBank bought British semiconductor company ARM Holdings, an innovator in the "internet of things," last year.