Storrs, Conn. — Students at the University of Connecticut School of Engineering enjoy a host of extracurricular opportunities, but few measure up to the hands-on experience provided by the UConn Formula SAE project. Organized by SAE International (formerly Society of Automotive Engineers), the Formula SAE (FSAE) series design competition challenges teams of university undergraduate and graduate students to conceive, design, fabricate, develop, and compete with small, Formula-style vehicles.
Teams have the chance to showcase their creativity and engineering skills by designing, building, and testing a single-seat racecar for the non-professional weekend autocross racer.
For the past seven years, the UConn FSAE team has traveled to Michigan International Speedway at Brooklyn, Mich., to compete in the annual international Formula SAE competition. CNC Software Inc., (Tolland, Conn.), the developers of Mastercam, has been the team’s title sponsor for the past several years. The partnership is a successful one: at the 2018 FSAE Michigan challenge, the team placed 13th out of 114 teams from around the world, its best finish to date.
The UConn student-run organization relies heavily on school aid and sponsorships, so teams are encouraged to use cost-effective engineering in their designs. Members design, fabricate, and analyze cost and performance of each car component.
“Every year, we’re standing on the shoulders of giants,” said Dylan Palin, mechanical engineering student and president of the University of Connecticut FSAE. “There’s a long history of brilliant members who made a lot of headway with difficult design, studies, and testing. Anything that the shop has today was built on the backs of great engineers.”
Palin adds that he is humbled by the talents of his current 30-person team, which is broken down into eight sub teams: Powertrain, Chassis, Data Acquisition (DAQ)/R&D, Electrical, Composites, Controls and Ergonomics, Business, and Budgetary. Many students join Formula SAE as aspiring designers and others have machine shop or technical experience.
One proven strategy to succeed in the FSAE competition centers on data analysis and testing of cars from previous years. Every summer, the UConn team runs testing and data validation and configures possible prototype designs. Summer’s end marks the beginning of the preliminary design phase; the team sets goals and makes modifications to the current set up, if needed. For example, after analyzing results from previous competitions, the team decided to incorporate a performance aerodynamic package into its car design.
“What’s great is that we don’t have to start from scratch,” said Palin. “There’s a wealth of information from past years. Each year, knowledge is passed down from returning members who understand the process.”
The starting point for building the racecar is the development of the chassis, which requires finalizing frame and suspension designs. As both components are designed around the tires, collecting tire data is the first step in designing the frame and chassis. Once the frame is built, teams complete preliminary designs for their components.
For construction of the frame, the team chose 4130 chrome alloy steel. For the wheels, the UConn group runs cast magnesium uprights for optimized weight reduction; 6061 aluminum and 4130 steel tubing are used for the suspension. Additional magnesium parts include the rods for differential mounts and the engine oil pan. In-house manufacturing is performed on CNC machining centers and manual mills and lathes. Team members use Mastercam to design their parts and run machine tools.
“This is a huge help for us because writing G-code is an acquired skill,” said Palin. “Mastercam makes it accessible for all of us. We do all of our design work in SOLIDWORKS.”
Users can program parts directly in Mastercam for SOLIDWORKS then access the Mastercam machining tree for quick access to any point in the machining process. Fully associative toolpaths permit changes without slowdowns, and updated Stock Modeling, Toolpath Verification, and Simulation features ensure user confidence on every project. The new Tool Manager function provides an efficient way to create and organize tooling assemblies. Once a part—no matter how complex—is programmed, job elements can be modified and toolpaths are immediately updated.
“Mastercam is used in-house during the manufacturing phase to machine our steering rack mounts, differential pillow blocks, bell cranks, and other small parts,” said Kenneth Brown, UConn FSAE chief engineer. “The Applications Team at CNC Software handles some of our more complex parts, including our combination hub spindle and sprocket adapter.”
For the parts that they machine in-house, UConn engineering team members use mainly 2D contour toolpaths because their racecar part geometries are not highly complex; 2D contour is a straightforward toolpath that is easy for new members to learn and use. Brown adds that the team relies on Verify, a Mastercam feature, that lets programmers check for gouges and view the finished shapes of parts in the Verify simulation screen. Productivity increases and problems are addressed before parts are ever cut. Programmers can verify on a separate thread while continuing to program, saving valuable production time.
“We really enjoy using Mastercam’s Verify feature when machining parts for the racecar because it allows us to check for tool collisions and make sure the selected toolpath and parameters machine the desired features,” he said.
One manufacturing challenge that the team faced involved standard machining and tolerancing of the frontal brackets and pillow blocks for the differential. In this case, running standard toolpaths for the sprocket adapter was not an option. The design has a standard bolt pattern but issues concerning tolerancing and blade speed arose. For parts that require machining beyond the university’s shop capabilities, the Formula team looks to the experts at CNC Software, Inc.
“CNC Software has done a lot of machining for us, especially on special design components like the sprocket adapter, one of our more unique designs,” said Palin.
The ongoing collaboration between University of Connecticut engineering students and CNC Software has a proven track record. Last year, the UConn team produced the fastest non-aerodynamic car without an aerodynamic package and was one of the only teams to complete the endurance requirement, arguably the most difficult leg of the FSAE competition. Palin notes that the team is proud of the fact that for six consecutive years, its racecar has not failed the endurance test.
‘Keep That Going’
“We hope to keep that going,” he said. “We run a pull-rod suspension, which very few teams do. We don’t have a million-dollar budget. We take pride in the fact that we make do with what we have in the shop.”
The endurance competition tests the durability and longevity of each car. According to Palin, this is where teams stand to lose the most points due to fatigue. Even teams with reputable programs may fail at the end of the 16-kilometer endurance run. Many factors must be considered in the design of each car, including weight, manufacturability, cost, and structural capabilities.
The 2018 UConn car demonstrated speed and stamina, accelerating from 0 to 60 miles per hour in less than 3 seconds. Estimated top speed was 80-plus miles per hour. Designing the multiple components required to construct a road-worthy racecar is quite an undertaking. When considering CAD/CAM software, ergonomics and hardware efficiency are important. The UConn team uses the SpaceMouse 3D mouse, coupled with Mastercam, to improve interactions with 3D applications.
The mouse’s controller cap can simultaneously pan, zoom, and rotate 3D content while the standard mouse—used in tandem with the SpaceMouse—is free to select menu items or parts of the model.
“When we maneuver the model, the 3D mouse makes it so much easier—especially on the system level components,” said Palin.
The long-standing relationship between UConn FSAE and CNC Software provides ongoing benefits to engineering students long after graduation. Several FSAE team members have interned with CNC Software and gained invaluable industry know-how. The entire Formula team enjoys real-world career experience by interacting directly with company experts, specifically the Applications Department.
“Our relationship with the Applications Department and CNC Software is fantastic and continues to grow,” said Brown. “Department members always rise to the challenge when asked to machine complex parts for peak performance of our car, and they give us feedback on how we can make our parts more manufacturable. The support they offer us is phenomenal.”
CNC Software will continue to partner with the University of Connecticut and other educational institutions to help pave the way for aspiring engineers. Hand-on experiences, like the Formula SAE project, are key to applying classroom knowledge in a future workplace environment.
“You can learn the theoretical math behind engineering design, but when it comes to critical thinking, problem-solving, and working with others, sometimes math and models do not represent reality,” said Palin. “Physically holding something that you have done the math on, analyzed, and designed, gives you a grip on what engineering can be in the real world.”