Design of a compact and mobile 3D Printer

Abstract

This project was focused on designing and prototyping a mobile robotic builder using additive manufacturing. This robotic builder is meant to be a part of a larger fleet of robotic builders that use swarm based strategies to build structures using simple behavioral rules. The concept was inspired by the biological phenomenon that are termites, whom are able to build large mounds with complex structures and architecture on the inside without having a centralized control unit. Separate agents that are able to efficient and effectively collaborate.
The project focused on designing a singular robotic builder for that context. The builder is supposed to be mobile, compact and able to climb its own structures. The builder was also supposed to utilize fused deposition modeling (FDM) printing as its main method of building, mimicking the depositioning of dirt by a termite.
Various brainstorm theories and processes were used to conceptualize different form factors of the robotic builder. All of the concepts were evaluated using standarized methods and further developed.
The final proposed design consists of two main components, the mobile platform and the 3D printer. The design incorporates a SCARA robotic arm for the 3D printing as it has many good properties that fit the context of the project while remaining relative simple in terms of kinematics. The mobile platform includes a whegs system to be able to climb its own printed structures and a leveling mechanism to be able to print in various orientations. The mobile platform was not further developed.
Iterations of the SCARA design were done using CAD software to reduce the development time. After evaluation, a final design was chosen that combined all of the best traits of the previous designs. The design’s main traits were that it was lightweight, simple, bare bones and highly customizable. Relative easy assembly was important as the design will be open-source. Off the shelf components were evaluated on its capabilities and integrated into the system as fit.
The final prototype, a SCARA printer, was able to produce promising results. The prototype was able to print faster than regular printers, print stronger structures and still be sufficiently accurate.
Additionally, a voxel based printing strategy was proposed to help improve the print time more and reduce material usage. The voxel-based approach offers the advantage of enabling a system to be fully optimized for its specific voxel requirements. Italsosimplifiedtheprocessandstrategyofusing FDM-printing in a less controlled environment.
The project provides a foundational design for future SCARA printers, paving the way for continued advancements in swarm robotic construction technology. The final SCARA design is highly customizable and adjust- able with firmware that matches those traits.
Although the project lays down a well thought out foundation, a lot more research and work must be done to properly develop a robotic builder that is ready to implement swarm strategies. The most crucial aspects are mobility, leveling and consistency. Additionally, further optimization of the SCARA printer as a whole and its voxel strategy is necessary.