A simplified approach to the calibration of extrusion based am systems

In the development of Additive Manufacturing technology not only the calibration of the process parameters but also the calibration of the devices used in these applications is fundamental. In extrusion based AM systems, the use of the parallel kinematic solution such as the linear delta configuration is commonplace. For these robotic architectures a wide range of calibration solutions are available in scientific literature capable of reaching a high level of precision, which is time consuming and costly in terms of measurement systems and computational complexity. For these reasons many of the former are often not suitable or required in AM applications. This article proposes a custom made calibration method aimed at respecting the technological tolerances of an AM process based on an extrusion system, in particular focusing on the linear delta kinematic solution. Typical tolerances of AM extrusion processes are set out, the calibration method explained, the mathematical model of the linear delta analysed and the results presented.