Hypercar thesis part 2: exterior design

The project has moved on since the last post - I have given up on repairing the NX assembly and just copied the new powertrain part into older backup assembly. Lost some progress, but most importantly lost a lot of time. That also left me without my academic NX license and I had to download a "Learning Edition", which on one hand was nice to have when I had nothing else, but it seems like it has less features than a full version.

Rear tunnels

After fixing up the assembly I struggled heavily with modelling of rear tunnels. What I wanted to achieve was a single, continuous shape that was easy to modify but still conforming to all the necessary constraints, most important of which was tangency to the bottom surface of the tub. After over a week of trying to make them the same way as front tunnels - meaning a shelled solid, I decided I had to learn the mystical skill of surfacing, about which I knew nothing since it was not covered in any classes.

Rear tunnels seen from the bottom back of the car.

As my thesis advisor pointed out, the floor definitely needs to extend from them sideways until it reaches the outer wheel line - increased floor area will lead to incresed downforce.

Exterior design

I was deeply dissatisfied with my initial attempts at styling and while what I've come to is still not perfect, it's getting closer to being acceptable. A big struggle was to hide the proportions as much as possible - the car has over three wheel diameters between the wheels and without a considerable effort it would look kind of like Mercedes CLR or just another copy of Valkyrie. The other part was making the car look good, and I had the usual struggles of amateur designers - a misture of bland, repetitive or badly proportioned ideas.

I actually like this and it reminds me of Caparo T1, but apart of the fact that this drawing has a ton of perspective errors, I wanted to make the car more like a road car, or maybe a bit 60s endurance racer type.

This was the sketch that became what the design is now. Believe it or not, I was inspired by B-1B Lancer bomber.

After some time, I decided to go the following way:

I started modelling the exterior after finishing this sketch. I actually like the toned down "60s-like" (and a bit of modern LMP1) front much more than what came later, but I just don't know how to make it look right from other angles.

Modeling the exterior (and coming back to the drawing board)

It was clear for me that I can't shape the whole body like I shaped the rear tunnels, because complexity would just drive me crazy (or at least I think so considering my surfacing skills). I found some obscure one to three minute long videos about NX Realize Shape feature and decided to give it a try. A few days later, this came out:

As you can see, some places already look good and some don't. What's frustrating is that I cannot use any tools external of Realize Shape mode to guide or constrain the curves or points, it's just a bunch of clicking and hoping the final shape would look good.
At this point I hit the wall - my design was too incomplete, and I had no other choice than "take a screenshow, draw on it, model drawn changes and repeat" cycle.

A screenshot with redrawn front. I also added these rough arrows to show which openings lead where.

I also finally came up with an idea for the back:

Yeah, my drawing skills got reeaally rusty...

But it seems like even sketching was not my biggest bottleneck.

 

Yep. What defeated me was freaking surface modelling. Also, what you can't see here is that between the dark grey sketch with flow lines and the pencil sketch of the back there is a month long gap caused by me not wanting to fail other subjects, mostly Aircraft Design I need to pass to even defend my thesis, and also bunch of other subjects on my Computer Science degree.

This means I have to postpone the defense of my thesis until September. It's a bit unfortunate, but I want to make this thing properly.

What's next

The next update will be about (admittedly late) underbody optimization. Up to this point the entire design was mostly qualitative, meaning that it was mostly my imagination and my advisor's experience. I have no proof that this would work and even had no idea if for example, cross sections of tunnels would grow in an expected manner!