If you’ve had any formal education, you’ve likely experienced a class that was long on theory, but short on real-life practice.
Students from Purdue Polytechnic Institute at Purdue University in West Lafayette, Ind., were experiencing this in their introductory fluid power class. Understanding the theories behind fluid power is important. However, feedback indicated that more hands-on work showing real-life application of fluid power concepts in action would improve the course.
As a precision electro-pneumatic component manufacturer, Proportion-Air in McCordsville, Ind., looks for employees who can immediately apply fluid power concepts. The company was finding the same thing in applicants that the students had in their class: plenty of theory, little practical application.
The stars aligned when Dr. Jose Garcia, a Purdue Polytechnic professor, gave a presentation at the 2015 Fluid Power Innovation & Research Conference. His topic, fluid power education, piqued the interest of a Proportion-Air employee in attendance. The two talked about the need for better fluid power curriculum, agreeing that there was potential to work together. After collaborating on smaller projects, discussion turned to designing kits for fluid power education. The Polytechnic’s capstone program for college seniors provided the ideal platform to include students in the process.
The first steps
Four Indiana residents signed up for the project. Jake Parsons, an electrical engineering technology major, was the team leader. Justin Laird, a double major in mechanical engineering technology and manufacturing engineering technology, served as secretary. Manufacturing engineering technology major Felicia Shadoan was budget manager, and Bryce Greenman, an electrical engineering technology major, held the project manager role.
Once the team was assembled, work began on the proportional pressure regulator demonstrator project, or “pneumatic lab,” as Proportion-Air dubbed it. The project had six “gates,” milestones that the students built their plan around.
They completed the first gate in late September 2017. It included creating a problem statement and a matrix outlining the team’s expected needs. After review and approval by Proportion-Air staff and Dr. Garcia, work began on Gate 2—design concepts. The team flew to Florida to meet Dan Cook, Proportion-Air’s corporate president and founder. Cook runs a satellite office, Proportion-Air South, in Gulf Breeze.
That trip was the highlight of the project for Parsons. “Dan had many different setups that we got to play with. We all took turns playing with a setup that controlled the size of a balloon with an ultrasonic sensor.”
The team turned in their design concepts after the trip and started on the third gate, process and project design. They settled on three labs: pressure, flow and temperature control. Completion of Gate 3 marked the end of the first semester, culminating with a poster presentation showcasing the team’s progress.
Greenman thought the work in the first semester was the hardest part of the project.
“We were tasked with a pretty big project, so learning about pneumatic concepts and thinking through the design process were all very challenging,” he said.
The second semester was about acquiring parts, assembling and testing. During Gate 4, the team finalized design plans and created a bill of materials. Gate 5 provided hands-on experience: building and testing prototypes.
With a little bit of inspiration from Proportion-Air staff, the team built the lab frame using 80/20 T-slot aluminum framing with a clear acrylic backing to mount components. They also designed an electrical control box: a power supply, switches, potentiometers and a microcontroller. The students chose an Arduino as the microcontroller for prototyping, writing a program for each of the labs to acquire the necessary data.
Prototyping the flow lab showed the team the value of closed-loop feedback, the cornerstone of the compaany’s pressure regulators. The team installed a needle valve that allowed manual adjustment of the flow going into the turbine. By controlling the flow, the team safely regulated the speed of the turbine, which was turning as fast as 24,000 rpm. In an open-loop system, when the needle valve is opened, flow increases and the output voltage of the turbine also increases. Using closed-loop design, the QBX regulator senses the increase in voltage and dynamically adjusts the flow to keep the voltage steady.
After building and testing with Dr. Garcia and his teaching assistant, the team tested their lab setups with students in the MET 230 class. Laird and Shadoan identified this part of the project as their favorite.
“The most fun/rewarding part of the project was putting all the final pieces together for each lab and testing them in a real classroom environment,” Shadoan said. “We got a lot of feedback from students on what we were doing right or how we can make improvements.”
Laird agreed. “They not only identified problems with our project but also talked about areas of the demonstrator kit that boosted their understanding of the desired pneumatic principle.”
Wrapping it up
Gate 6 was the finish line. It ended in another poster presentation. Now that the project is over, each student was asked to reflect on what he or she would have done differently if they could start again. The answers ranged from prioritizing certain elements earlier to managing expectations. Parsons, the team leader, identified the electrical aspect as one the team didn’t foresee taking as long as it did.
“We wouldn’t have underestimated the length of time it takes to do all of the electrical work,” he said. “We spent an extra 2 weeks on the electrical side of the project than what we originally scheduled for.”
The end of the school year brought graduation for three of the students. Greenman will move to New England to take an electrical engineer position with General Dynamics Electric Boat in Groton, Conn. He’ll join a team that designs communication and control systems for the main propulsion machinery in nuclear submarines. Laird has accepted a manufacturing engineer role with Caterpillar in West Plains, Mo. Shadoan is still looking for a job, focusing on engineering or technical sales.
Parsons will spend the summer interning with Stanley Security. He’ll return to school in the fall for a final semester and graduate in December.
The three labs the team built will stay at Purdue for use by students in future fluid power courses.