University of Technology
Warsaw (Poland)
Unmanned aircraft development
SAE Aero Design
Sinterit’s SLS 3D printing technology was one part of the success that the SAE Aero Design student association from Warsaw University of Technology achieved in prestigious competitions in the United States.
SAE Aero Design is a series of competitive aerospace and engineering events that have been held in the US since 1986. The intent of the competition is to provide engineering students with real engineering challenges. The Polish team from Warsaw University of Technology has participated in these competitions for 31 years as one of the favorites. This year, the team won three main prizes in two editions, East and West, first and third in different categories and in total stood on the podium thirteen times.
The purpose of the SAE Aero Design Competition is to design and build an unmanned aircraft capable of lifting the heaviest possible payload. There are three categories of aircraft: Micro, Regular and Advanced. Parts printed on Sinterit’s SLS 3D printer were used in the regular printer. What were the assumptions?
The aircraft, built under normal class rules, had to have a wingspan of 120 to 216 inches, a takeoff of up to 100 feet, and electric motor power limited to 750 watts.
A team of 20 students worked for six months to develop six models: four in the micro category and two in the regular category. Since the SAE Aero Design Competition has two parts, East and West, the Polish team decided to compete in both.
Aircraft design and preparation
The quality and precision of the parts together with their low weight are crucial in the aerospace industry. Using Sinterit’s Lisa X SLS 3D printer was a natural choice. A key feature of the MSP technology is the virtually unlimited freedom in geometry design, which, together with the isotropic mechanical properties of the print, has led to the production of strong and lightweight parts.
“SLS printing allows us to design parts with complex geometry and precision not achievable on FDM/FFF printers. This is essential in weight loss. Also very important are the virtually isotropic mechanical properties of the finished print (as opposed to FDM/FFF printing). This allows for a much freer design of the elements”, says Michał Włodarczyk, coordinator of the standard class aircraft.
Students from Warsaw University of Technology designed one of the tail boom assembly elements of the R23 (aircraft name) with SLS technology in mind. The tail boom mount transmits very high forces and moments and is also a very important structural element. The virtually unlimited geometry design possibilities made it possible to produce a very light and durable element.
Competition
SAE Aero Design East was held at Paradise Field in Lakeland, Florida. During the three days of competition, the aircraft, called “Czapla” (heron), performed eight flights with a maximum load of 7.47 kg and a curb weight of 8.7 kg. The team finished fourth overall.
A month later at Thunderbird Field in Fort Worth, Texas, “Czajka” made eight flights, this time finishing third in the regular season, beating sixty teams from around the world. The Aero Design West competition brought the final victory in the micro class, in which the Warsaw University of Technology team won first prize.
As this was the 31st entry in this competition, but the first using SLS 3D printing technology, it opens up a good prospect for the future and even better use of advanced 3D printing capabilities in the production of winning aircraft.
