An introduction to modular joints for collaborative robots collaborative robot fabrication techniques

Modular robots are a robot development system consisting of a series of standard joint modules connection modules. Modular joints are the central components of modular robots , each modular joint has a standard mechanical electrical interface. The outstanding advantages of modular robots are reconfigurability, easy maintenance, high flexibility reliability, they have a wide range of application prospects.

      Based on the modular planning thinking proposed in the National 863 Program Project "Integrated Service System of In-cabin Robots in Space Laboratory", this paper carried out the planning research of modular joints. Based on the analysis of the current status of modular joint research at home abroad combined with the requirements of the project, the planning analysis of the overall plan of modular joints were completed.

      According to the task requirements of the modular robot, the maximum torque of each joint of the module is calculated by a step-by-step recursive method top (end gripper) to bottom (base). A relationship model between the module geometric size error the robot's end gripper's maximum position error is established, the robot's end gripper's maximum position error is calculated using this model.

      Finally, the design goal of the modular joint was determined, the selection of the main components of the modular joint was completed. According to the technical requirements of the three-branch modular robot, a modular design concept was adopted to design a robot modular joint that integrates the mechanical system, drive system, sensor system, control system power system, has a standard mechanical electrical interface. A joint torque sensor based on the strain principle a cross-distributed elastic beam structure was specifically designed to enable the joint to have torque bending moment overload protection capabilities. The selection of modular joint materials, specific structural planning, routing planning, system integration planning, multiple connection module planning were completed.