Students in the department of aerospace engineering at the University of Maryland A. James Clark School of Engineering are using high-tech 3D printers for a range of projects including analysis of alternative modes of flight for potential military applications.

As part of the department’s research in this area, faculty and Ph.D students frequently subject numerous identical prototypes to the same experiment repeatedly to increase testing validity. This effort requires engineers to create multiple, and often tiny, test objects with 100% identical characteristics.

Students used 3D printing to create a model for the annual Cessna/Raytheon Missile Systems Student “DesignBuild/Fly” competition.

For years, the department sought the best method to produce large volumes of highly accurate testing prototypes. Under the direction of Professor Darryll Pines, dean of the Clark School, several 3D printing technologies were explored to improve the testing process. Ultimately, the school selected the Objet Eden 350V unit based on its resolution, accuracy, detail, and durability.

According to Pines, the printer had an immediate impact on productivity because it helped speed up research and testing processes by enabling the engineers to develop specimens faster and to recover more quickly from design process errors. “The printer technology reduced the prototype development cycle by a full year and yielded a cost savings of approximately $80,000/yr. It eliminated the need to pay for homemade prototype material such as aluminum and plastics that outside vendors marked up by nearly 1,000%,” He also added that the printer enhanced the validity of the department’s research findings by ensuring that test objects are always 100% identical.

Evan R. Ulrich, a graduate research assistant candidate in the department, commented that all aspects of the testing apparatus are now constructed with the printer.

He notes that there is no waiting on other people since he and others can produce their models in-house at a faster rate than before.

One of the university’s many applications of this technology was the examination and relation of how insects avoid obstacles during flight. The department used the Eden system in the design and manufacture of the first structure used aboard small helicopters that allowed sensors to test for close obstacle avoidance. It was reported that the Objet system reduced, by months, the time it would have taken to complete this research using prior methods.

The engineering department developed and manufactured the first structure used aboard small helicopters that allows sensors to test for close obstacle avoidance.

Ulrich has also seen the benefits of this technology in his own research activities, using Eden-generated models to study how the distinct flight patterns of winged plant seeds falling from trees might have application in unmanned vehicles. “The capabilities of such vehicles are often limited by the power required to simultaneously maintain flight and operate onboard electronics,” said Ulrich.

“But the flight mode exhibited by winged seeds requires little to no power. Using the Eden, he was able to quickly and cost-effectively test numerous design iterations leading to the invention of the smallest controllable robotic samara to date.

In addition, Ulrich – with a team of fellow students – used the Eden to create a model for the annual Cessna/Raytheon Missile Systems Student “Design/Build/Fly” competition. Organized through the American Institute for Aeronautics and Astronautics (AIAA), the contest challenges students to design, fabricate, and demonstrate the flight capabilities of an unmanned, electric powered, radio-controlled aircraft. The model had a four-foot wingspan and detailed specifications for wind tunnel conditions. The Maryland team finished very high in the competition.

“3D printing technology has proved itself as an asset that can help engineers and those who train them to better execute some of the most sophisticated and technical

research studies in the world,” said Pines. “It represents the future of aerospace studies and will surely help our best minds achieve the next generation of scientific breakthroughs.”

Objet Geometries
www.objet.com

University of Maryland
www.eng.umd.edu

MPF