No Rest For the Studious: The Story of the University of Delaware BHR14 (Part 1)


Is this still making sense?  Unfortunately I have lost a number of our CAD renderings, so we'll skip straight to the chase with the final mockup.  We're doing our best here!  Anyway, with this render, you can see the suspension fully mounted.  The dampers are mounted high on the nose of the car.  This reduces the load on the rocker pivots (which can be upwards of 2,000 lbs) and puts them in a location that can be triangulated in the frame.  Also note the intake (which is actually higher than it should be).  True CAI!  On the 2013 car, intake air was sucked from the engine bay, sandwiched between the roll bar mounted radiator and engine.  The radiator in the 2014 car would be side mounted and also much, much smaller.  The 2013 car used a radiator from an EG Civic.  Despite its huge size, the car would overheat on very hot days (like say, a June afternoon in Lincoln) due to lack of airflow (with the radiator behind the driver's head, the front of the radiator had to be shrouded to prevent the driver from being scalded if the radiator or hoses failed).  For 2014, we would use a Yamaha YFZ-450 radiator, along with an oil cooler to shed combustion heat.  The YFZ radiator, complete with a high flow fan and custom carbon fiber shroud, was taken directly from the 2011 UD SAE car.  Fun fact: we named our mock up driver Carl.  It was done at 1 AM and I have absolutely zero recollection of how he came to be named Carl! 
From the top, you can see where the radiator sits.  You can also see the new rear suspension box, complete with diff mounts.  Dig the rear shock mounts: they double as engine mounts, taking advantage of the beefy engine block to support the suspension loads.  The engine is only lightly stressed in this design.  We considered making the engine fully stressed, but there were enough horror stories of teams with spun bearings and weak compression that we decided against it.  Another neat feature of the rear suspension is how the rockers and dampers are actuated in nearly a straight line.  This greatly reduces loads on the rocker pivots (preventing binding) and allows this rocker to have a slightly progressive motion ratio, allowing the car to run softer springs.  Please ignore the bad toe-in.  SolidWorks can be fickle when it comes to rod end assemblies.  
The intake is a preliminary design, but the plan would be to take advantage of UD's new 3D printers.  The fuel injectors would be housed in the factory throttle bodies (with the throttle blades removed).  This would allow us to print the intake manifold in ABS and not worry about the heat of the engine, or the effects of gasoline on ABS plastic.  And yes, we know the air filter goes through the roll bar.  The real intake would need to be much smaller, as SAE rules prohibit any part of the car extending above the rollbar.  Remember, this entire car was designed in just over 2 months!  In fact as these three renderings were being finished, the car was already under construction.

Did someone say construction?  Here we have an SAE-car-in-a-box (some assembly required).  The entire chassis will be made from 1″ chromoly steel tube.  Wall thickness ranged from 0.095″ (for the roll hoops) to 0.029″ (for support tubes).  For the suspension and engine mounts, square tube was used.  We also had 3/4″ tube for the pushrods, 5/8″ tube for the control arms, 1/2″ tube for the anti-roll bars, and 1-1/8″ tube for the roll hoop sleeves.  This, by the way, still wasn't enough tube to build an entire car.  While pros would have tons of tube leftover, us n00bz wasted a decent amount in mistakes.  Hey, there's only one way to learn how to cut, notch, bend, and weld, and that's to roll up your sleeves and do it.  
The cutting oil is in the air!  The fun is only just beginning.
But you're going to have to tune in next time to see these pretty aluminum blocks and steel tubes be cut, welded, machined, and finessed into a racecar.  Next time we'll be show how the above box of tubes grew into a car, like a metallic Frankenstein child.  There are tons of late nights, busted knuckles, frozen computers, and midnight Wawa runs in store for us as we turn our ideas into reality, strap into our creation, and pray we didn't divide by zero.

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