Low-Level Control of 3D Printers from the Cloud: A Step toward 3D Printer Control as a Service

Abstract

Control as a Service (CaaS) is an emerging paradigm where low-level control of a device is moved from a local controller to the Cloud, and provided to the device as an on-demand service. Among its many benefits, CaaS gives the device access to advanced control algorithms which may not be executable on a local controller due to computational limitations. As a step toward 3D printer CaaS, this paper demonstrates the control of a 3D printer by streaming low-level stepper motor commands (as opposed to high-level G-codes) directly from the Cloud to the printer. The printer is located at the University of Michigan, Ann Arbor, while its stepper motor commands are calculated using an advanced motion control algorithm running on Google Cloud computers in South Carolina and Australia. The stepper motor commands are sent over the internet using the user datagram protocol (UDP) and buffered to mitigate transmission delays; checks are included to ensure accuracy and completeness of the transmitted data. All but one part printed using the cloud-based controller in both locations were hitch free (i.e., no pauses due to excessive transmission delays). Moreover, using the cloud-based controller, the parts printed up to 54% faster than using a standard local controller, without loss of accuracy.

Distributed manufacturing for and by the masses

“…With advances in Industry 4.0, manufacturing machines (including low-cost 3D printers) are increasingly equipped with sensors and cloud connectivity (12). The large amounts of data generated by these sensors are being used in machine-learning algorithms to provide predictive and corrective actions (13).…”

A Secure Data Infrastructure for Personal Manufacturing Based on a Novel Key-Less, Byte-Less Encryption Method

“…As with software and faster computing, this move improves hardware operation, with incredible increases in quality and speed. For instance, Okwudire et al [11] sent a low-level stepper motor commands from a server to simplified firmware, which interpreted simple commands and proxied them to the stepper motor drivers. They measured an increase in printing quality and speed.…”

Corner accuracy in direct ink writing with support material

“…If the translation speed is not reduced to zero at a corner, the rapid change in direction and speed that occurs at the corner induces vibrations in the 3-axis gantry. [7,11] These vibrations produce oscillatory deviations in the print path which effectively widen the printed line at the corner (Fig. 4B).…”

“…[7,9,10] Ringing occurs because rapid changes in print direction can induce vibrations in the positioning gantry which manifest in ripples on the surface of the printed structure. [11,12] Slower translation speeds limit the impacts of smoothing, swelling and ringing but also limit the throughput of extrusion-based techniques, so alternate strategies for limiting these effects are needed.…”

“…Previously, strategies for mitigating the adverse effects of smoothing, swelling, and ringing have been studied for fused deposition modeling, where inks are viscous enough that capillarity can be ignored. [7,11,10,12] Strategies for mitigating the adverse effects of smoothing have been studied for direct liquid writing, where ink viscosities are low enough that viscous dissipation can be ignored. [8] However, DIW encompasses inks with a wide range of rheological properties, and a model is needed to describe the corner behavior of inks within a viscosity range where viscous dissipation and interfacial energies are both significant, such as the dental resin-based inks used herein or many hydrogels.…”