Motion error analysis of modular self-reconfigurable robot M-Cubes based screw theory

In the process of self-Reconfigurable for modular robot, the module\´s assembly, connection, transmission, cantilever deformation and joint flexibility would affect the pose error of the execution module in the end, which would cause the adjacent module not to be properly connected, so the position and orientation of the end module must be calibrated. For analysis, various error factors were attributed to the error of structural parameters and movement variable of the robot. On the "L" structure of the modular reconfigurable robot M-Cubes, the forward product of exponential error calibration model was derived by the nominal coordinate system built on the link coordinate system, in which the rotation coordinate transformation and the translation coordinate transformation caused by the error factors to the nominal coordinate system was amended. The calibrated model would be applied to the "L" structure of the self-reconfigurable robot M-Cubes, which properly calibrate the pose error of the rotary joint axis and hole in the end execution module, and ensure properly connected with the adjacent joints. The foundation was laid for the self-reconfigurable robot.