A Plane Projection Based Method for Base Frame Calibration of Cooperative Manipulators

Base frame calibration is the foundation for the cooperative work of manipulators. The commonly applied method usually constructed a matrix equation. The contact-mode approach is limited by the insufficient accuracy and efficiency while the high cost impedes the application of methods with the noncontact mode. In this paper, a projection-based method is proposed. All the transformation parameters can be solved based on the geometric constraints. When cooperative manipulators form the closed-chain asynchronously, the topological structure is projected into a particular plane. The rotation angle and translation parameters can be determined with utilization of trigonometric functions and a simple calculation process. The greatest novel feature of this analysis is that only two calibration points are required. The experiment result shows that both the accuracy and efficiency can be much better in the asynchronous calibration.