With news breaking late last week that Google has acquired cutting-edge robotics firm Boston Dynamics, we thought it would be a good time to check in on just how many different kinds of robots the company has as part of its growing army of androids. After all, Boston Dynamics is the eighth — yes, eighth — robotics company that Google has scooped up in just the last six months. So if we’re going to be bombarded with new Google robots over the next few years, it would be a good idea to get acquainted with them.

Robot No. 1: Cheetah. This Boston Dynamics creation does exactly what you think it does: It runs very fast. As you can see in the video below, the Cheetah tops out at a maximum speed of 28.3 miles per hour, which just happens to be a little faster than Olympic sprinter Usain Bolt runs on his best day. The robot was designed with funding from the Defense Advanced Research Projects Agency (DARPA), so it will likely have military applications in the future if it’s ever unleashed upon the world. Boston Dynamics this year took off Cheetah’s training wheels and started testing it over rougher terrains.

Robot No. 2: The Dreamer Sociable Head. As a joint collaboration between Google-owned robotics company Meka and the HRC Laboratory at the University of Texas Austin, Dreamer is an attempt to make a humanoid robot with a diverse range of facial expressions that are supposed to “elicit a sense of trust and sociability to an otherwise pure mechatronic device.” What makes this robot particularly impressive is just how many different expressions Meka and the HRC Laboratory can conjure using only mechanical eyes and ears to show how the head is “feeling” at a given time. It makes you wonder just how convincing the head would be if they designed a realistic mechanical mouth to go along with it.

Robot No. 3: Schaft. Who’s the ‘bot that won’t cop out when there’s danger all about? In all likelihood it’s Schaft, a robot designed by a team of engineers at the University of Tokyo whose goal was to make the world’s strongest humanoid robot. As this article at IEEE explains, the researchers made Schaft significantly stronger than other robots by equipping it with “high output capacitor-powered, water-cooled motor systems” that help it maintain balance when shoved. Schaft’s creators see it being used as a disaster response robot where it will be able to help conduct rescue operations in situations that are too dangerous to send in people.

Robot No. 4: BigDog. BigDog, another Boston Dynamics creation, may not be as fast as Cheetah but it’s certainly a lot more powerful. This hulking four-legged robo-beast is designed to go over rough terrains and, like Schaft, maintain its balance even when shoved forcefully. Even when the Boston Dynamics team sends BigDog onto a particularly slippery patch of ice, it never completely falls over — rather, it stumbles a bit, regains its balance and keeps on walking. The one downside to BigDog seems to be that its speed tops out at around 5 miles per hour, although we imagine that Boston Dynamics will be taking some of the lessons it’s learned from designing Cheetah and apply them to its monster ‘bot.

Robot No. 5: The Meka M1 Mobile Manipulator. After the somewhat scary BigDog, we’re going to close out with the much more human-friendly M1 Mobile Manipulator, which Meka designed to be much more of a personal helper robot. While it doesn’t have the same range of facial expressions as the Dreamer head, the M1 is much more useful since it has, among other things, hands that it can use to hold things, wheels that make it mobile and an expandable torso that lets it reach objects in high places. It also senses its surroundings through the same Kinect technology used in the Xbox so it’s not liable to go bumping into things.

Taken together, Google has acquired an intriguing set of robots with very diverse skill sets and applications. It looks like Andy Rubin is going to have a lot of resources and talent at his disposal to make some truly incredible machines in the coming years.