TYCOON: modular robot capable of torque synthesized collaboration with complementary intermittent gear mechanism

Modular robots, which can form various configurations by connecting multiple modules, have the ability to perform diverse tasks by reconfiguring themselves. However, due to the torque limitations of a single module, lifting multiple modules simultaneously is challenging, making it difficult to construct manipulators for manipulation tasks. In this study, we propose TYCOON (modular robot capable of Torque sYnthesized COllabOratioN), a modular robot that can synthesize more torque by transmitting torque between modules. In conventional modular robots, each module functions as a joint when assembled (joint-drive function), enabling them to lift or rotate other modules. TYCOON modules have an additional torque-transmission function that enables modules to transmit their torque to adjacent modules, allowing the torques of multiple modules to be synthesized and increasing the driving torque per joint. To realize this, TYCOON employs a Complementary Intermittent Gear Mechanism consisting of two gears with complementary teeth, ensuring that when one gear is engaged the other remains disengaged, achieving two functionalities with a single drive mechanism. Evaluation experiments showed that while a single module could lift only two modules, TYCOON could lift up to four connected modules. This capability enabled a 6-DOF serial-link manipulator, demonstrating the effectiveness of torque transmission in modular robots.