The QFR18 chassis is an evolution of Queen’s Formula Racing’s successful 2017 chassis. Rather than a complete revolution, it is built on the strengths of last year’s design, which helped QFR achieve seventh position at last year’s Formula Student UK competition.
The chassis team’s main objectives were to reduce mass and increase stiffness while accommodating a range of driver sizes. The result was a mass reduction of 6% over its predecessor and a torsional stiffness of 1928 Nm/°, well over the desired minimum value of 1500 Nm/°.
“The chassis design is tightly controlled by the competition rulebook,” said team member, Jonathan Garrett.
“But we were able to redevelop some of the key areas of the car, including the rear of the chassis which now features swept-back wishbones.
“This redesign reduced the overall mass of the chassis and improved accessibility to the engine and drivetrain for maintenance.”
Once a final design was agreed, the new chassis was designed on SolidWorks. It was then tested and refined using Abaqus FEA software, to ensure it complied with the necessary Formula Student rules and met the team’s own targets.
After research and analysis of potential materials, BS4 T45 carbon steel was selected for use in the chassis. Once the final design had been completed, QFR partners, Hutchinson Engineering, laser-cut the 83 tube members to the correct profiles.
Using QUB’s prototyping workshop, eight sets of laser-cut MDF jigs were manufactured, locating the chassis members accurately and securely for the tacking and brazing processes.
“Once we received the laser-cut members from Hutchinson Engineering we were able to braze the chassis with the help of the bespoke jigs,” explained Roger Dawson.
“The main jigs were set onto the weld-table, which was used as an accurate datum reference for design.
“Additional jigs for the engine mounts, steering column and shoulder bar ensured accurate positioning of these components within the chassis.”
These improvements considerably reduced the assembly time of the chassis, resulting in the chassis’ completion before the Easter break. This gives the rest of the team more time to add their own components to the car ahead of the car’s launch and test programme.