Volumetric error compensation for multi-axis machines

A general error prediction and compensation scheme which implicitly includes the non-rigid body condition is developed for an arbitrary multi-axis machine. The accuracy and precision of tasks performed by multi-axis machines are profoundly affected by their volumetric accuracy. The volumetric accuracy of a machine depends on numerous factors, including geometric and kinematic errors, motion induced errors, deformation of structural members due to static and dynamic loads, and thermally induced errors. To alleviate the influence of these factors on the outcome of a task, a passive online software compensation method is developed. The method is based on two components: an interpolation algorithm with shape functions for error prediction and a recursive online software compensation scheme. Several illustrative examples are included