Smithsonian.com

Image: Gontzal García del Caño

Forget Arnold Schwarzenegger or Tom Brady: the newest robots will take those strongmen’s muscle tone to task. The Kenshiro Robot, unveiled this month at the Humanoids conference, imitates the bone structure and musculature of a human. IEEE Spectrum reports:

Kenshiro mimics the body of the average Japanese 12-year-old male, standing at 158 centimeters tall and weighing 50 kilograms. Kenshiro’s body mirrors almost all the major muscles in a human, with 160 pulley-like “muscles”—50 in the legs, 76 in the trunk, 12 in the shoulder, and 22 in the neck. It has the most muscles of any other bio-inspired humanoid out there.

Here’s what the thing looks like:

It’s hard to build a human like robot with muscles and bones because humans actually weigh a lot. IEEE explains:

Why try and mimic the human body? It turns out that getting a robot’s weight right is a tricky problem. Yuto Nakanishi, the head of the project, spoke about the weight problems of Kenzoh, Kenshiro’s tendon-driven upper-body robot ancestor. Kenzoh was a hearty 45 kg, just for the upper body. Scaling up, they projected that a full-body Kenzoh could weigh as much as 100kg!

That was a lot of weight for a relatively small robot. So they decided to design a robot with the same weight ratios of a human. For example, a 55 kg boy would have about a 5 kg thigh and 2.5 kg calf. Kenshiro copies that ratio, with a 4 kg thigh and 2.76 kg calf. Balance is key.

You might feel big and clumsy sometimes, but your body is actually quite finely tuned.

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