- Who
- Kengoro, Department of Mechano-Informatics, University of Tokyo
- What
- 174 total number
- Where
- Japan ()
- When
The humanoid robot with the greatest number of degrees of freedom is Kengoro, designed and built in 2016 by researchers from the Department of Mechano-Informatics at the University of Tokyo, Japan. As of 29 January 2019, Kengoro has a total of 174 degrees of freedom (including 30 in each hand).
The term "degree of freedom" is used in robotics to describe an axis of movement in a joint. An individual joint has three possible degrees of freedom – pivoting up and down, pivoting left and right, and twisting clockwise and counterclockwise. A human knee or elbow, for example, has one degree of freedom while a hip or shoulder has three. To calculate a robot's total number of degrees of freedom, the values for each joint are added together.
Kengoro has a dramatically greater number of degrees of freedom due as a result of the design of its flexible upper body. In a robot such as Honda's Asimo (57 degrees of freedom) or Boston Dynamics' Atlas (28 degrees of freedom) the torso is a rigid case containing the motors and batteries. Kengoro, by contrast, has a human-like spine composed of multiple machined-spring joints (each with three degrees of freedom). There are five machined-spring joints at the base of the spine (mirroring a human's lumbar vertebrae), six one-degree-of-freedom joints for the "vertebrae" connected to the ribcage, and another seven machined-spring joints in the neck (mirroring the cervical vertebrae).
Additional flexibility comes from the design of Kengoro's shoulders, which are composed of three ball joints on each side to mirror the flexibility of the human shoulder (as opposed to the single ball joint seen in other robots).
To control these joints, Kengoro has 116 individual motors, working with tendon-like cables and muscle-like springs.
