Researchers from the JSK Lab at the University of Tokyo have developed a highly advanced robotic forearm that closely mirrors the proportions, weight, muscle arrangement, and joint performance of a human arm. This innovation marks a significant leap forward in robotics, offering enhanced capabilities for future humanoid machines.

To achieve this, the team integrated two muscle motors into a single module that also functions as the forearm’s bone structure. This efficient design saves space by using shared components, and a heat dissipation method allows motor heat to be transferred through the bone. The result is a radioulnar joint that perfectly mimics human anatomy, offering precise control and fluid motion.

The robotic forearm has been tested with tasks such as soldering, opening books, and even swinging a badminton racket, demonstrating its ability to perform complex, human-like motions. Recent developments in robotics have focused on creating humanoid robots that replicate human joint structures, and this new forearm design is a key advancement in achieving lifelike movement.

One of the unique features of this project is its detailed replication of the radioulnar joint, a structure often overlooked in robotic design. While previous tendon-driven robots struggled to accurately mimic this joint, the team’s innovative bone-muscle module overcomes these challenges. By integrating miniature motors and developing an ultra-compact tension measurement unit, the researchers reduced the module’s size by 39%, improving performance without sacrificing accuracy.

This new forearm design incorporates eight muscles within the radius and ulna, controlling six degrees of freedom (DOFs), including wrist and finger movements. The compact, efficient structure ensures that the robotic forearm maintains the proper body proportions while providing greater muscle-driven movement capabilities than previous models.

In achieving human-like joint performance and precision, this breakthrough design could transform the field of robotics, enabling next-generation humanoids to perform intricate tasks with the skill and dexterity of a human arm.

By Impact Lab