Study on three-dimensional active cord mechanism: development of ACM-R2

Describes the development of ACM-R2, which is new version of the active cord mechanism with 3D mobility. This ACM-R2 has installed a driving mechanism called "M-drive". This mechanism enables the ACM-R2 to acquire a high output/mass ratio and torque limiting joints, which works as a normal joint and deforms under excessive torque. It has also installed a new type of torque sensor, the "float differential torque sensor" on each joint. Additionally the ACM-R2 has also a self-contained structure with control computer and battery in the joint units. These specific driving mechanisms and the self-contained structure enable ACM-R2 to demonstrate new propulsion methods and motions combining the ability of a manipulator and a locomotor.