We are measuring a static target with a moving platform. So it’s pretty much uncharted territory as far as Digital Image Correlation.”

Not only is building a drone a dream project for a group of Kettering University students, but the project could help ensure safety of community structures.

Four students -- Ben Fick ‘17, Matt Hoskins ‘17, Sean Catt ‘17 and Joe Praski ‘17 -- designed and programmed a drone with a pair of high speed cameras that can capture up to 160 frames per second in order to detect displacement, strain or defects in structures such as bridges, dams and wind turbines.“The purpose of the project was to create a mobile platform for digital image correlation cameras,” said Catt, a Mechanical and Industrial Engineering major. “We felt the best way to go about that was to build a drone seeing that you can control that from the ground. And the purpose of that was to be able to use it to scan crumbling infrastructure or scan bridges or buildings where it would be difficult to get conventional camera rigging.

“We can take it essentially everywhere and fly it in areas where you typically couldn’t reach.”

The capstone project was for the students’ MECH 514 (experimental mechanics) course. Dr. Javad Baqersad was their faculty advisor.

Kettering University students show off the drone they used in their capstone project

Nowadays, drones are emerging as a robust tool for structural monitoring. However, the current drone systems can only take photos and videos that are used for qualitative assessment, Baqersad said.

“The purpose of this project was to develop a structural health monitoring system that can generate quantitative results for periodic damage detection and performance evaluation. This system can be used for monitoring large infrastructures and wind turbines. Monitoring and restoring the infrastructures is one of the National Academy of Engineering Grand Challenges for Engineering,” he said. “The students selected a challenging topic for their capstone project. I was truly impressed by their dedication and perseverance to accomplish this project.”

In under 10 weeks, the students were responsible for designing the drone, designing the camera mounts and programming three microprocessors -- flight controller, a manual control and the processor to take photos when it’s a certain distance away from the structure. They also needed to calibrate the cameras and perform a sample measurement.

The students use Digital Imaging Correlation (DIC) technology to process images and formulate a result. DIC is a 3D, non-contact optical technique to measure contour, deformation, vibration and strain on almost any material.

“We chose this project because it simplifies the process involved and it’s furthering the applications of this new technology rather than time consuming expensive set ups that includes an entire day process with equipment like cranes,” said Hoskins, a Mechanical Engineering major.

“Just as any engineering application is designed to do we are here to simplify a process. The drone itself is just to make something that’s new easier to use so we can continue using it in the future.”

It’s a complicated process using the DIC technology, Praski said. DIC usually uses a static set up and a static target, but with the drone, the students are doing the opposite.

“An example of a conventional application would be to measure the rotational displacement of a helicopter blades from a static set up. And we’re kind of doing it backwards. We are measuring a static target with a moving platform,” he said. “So it’s pretty much uncharted territory as far as Digital Image Correlation.”

Once the students had the drone up and running, the process to assess a structure requires a few more steps. To determine if there is any displacement, strain or deformation, the team would first need to place track points or a speckled pattern on the structure being measured.

The drone would then be flown toward the structure with photos being taken once the drone is a certain distance from the structure. Using a reference photo the data processing software is able to measure defamation and ultimately strain in the structure.

“A client would receive a final product of the different strains and key critical points along the structure so if there is a particular wear point that will need additional maintenance maybe every year or two years,” Fick said.

After fine tuning their design and doing further development, the next step in the process is to create an instruction manual to train people on how to use the new technology, Hoskins said. They plan on implementing laser range finders and obstacle detection.

During the project they discovered that the application of things they learn every day can be assembled in a different order to create something that’s completely new using seemingly simple tasks learned in class, he said. Now the hope is that they can share what they learned with others.

“Our goal with this project was not just to create something new and then let it sit. Ideally we would like to see all of our hard work go toward a goal of achieving something that hopefully will catch on in the future,” Hoskins said. “We would love to see this being used in a real market and a real application.”