Researchers at the Nanyang Technological University (NTU), Singapore have 3D printed a ready-to-fly drone in an aerospace-grade material. What's special is that this was achieved in a single production step, including all of the required electronics.

The drone was jointly developed by NTU’s Singapore Centre for 3D Printing (SC3DP) and Stratasys Asia Pacific, a subsidiary of Stratasys Ltd.

The printing process used ULTEMTM 9085, a high strength, lightweight Fused Deposition Modeling (FDM) material that is certified for use in commercial aircrafts. ULTEM 9085 is prized for a high strength-to-weight ratio and FST (flame, smoke and toxicity) rating, making it suitable for the commercial transportation industry, especially aerospace.

Getting flight-ready

The drone, a quadcopter with four rotors, was designed, 3D printed and flown by Phillip Keane, an NTU PhD candidate from the School of Mechanical and Aerospace Engineering.

In 3D printing, objects are created digitally layer by layer until completion. However, embedding electronics can be a challenge, as most will not survive the high temperatures of the 3D printing process.

Commercial grade electronics were therefore modified and placed within the drone at the various stages of the printing process. They survived the high temperature printing, which reached over 160°C, compared to the usual 80°C to 100°C.

The motors and the propellers were, however, mounted after the entire chassis was completed.

"One of the toughest challenges was to find electronic components that could theoretically survive the high temperature printing process," said Keane in a press statement.

NTU Stratasys3DPrintedULTEMdrone cr Figure 1: Close up of the embedded electronics inside the NTU-Stratasys 3D printed ULTEM drone.  

The drone was completed in under 14 hours. During the printing, there were just 3 pauses for the electronics to be placed within the chassis. "The housings which were pre-printed in ULTEM 9085 also provide a flat surface for the 3D printer to continue printing over them," added Keane. "I also had to deal with tight time constraints as some of the components could not survive in the heat for more than 20 minutes."

NTU PhillipKeanewith3Dprinteddrone cr Figure 2: NTU PhD Student Phillip Keane with the 3D printed drone in front of the Stratasys printer. He had to add heat-proofing modifications to the components. This involved adding new components to the PCBs and also designing custom housings.  

The drone is rugged enough to support over 60kg of weight suspended from its structure. Keane is planning to work on the next version of the drone, which will feature better durability, lighter weight and improved flight dynamics.