For side paneling, we used smoked Polycarb and white vinyl.
Additionally to what @EricH said, how the robot moves is important too. I robot that almost seems to “dance” through the field is going to look more elegant that one that jerks along.
It might seem like a non-answer, but well designed robots are typically beautiful because they have a beautiful method of solving the challenge on hand.
Painting your robot does not make it aesthetically pleasing unless you can do a really good paint job. A bad paint job is guaranteed to make your robot look terrible. Most of the best looking robots follow the suggestions @EricH already made.
Painting also takes extra time so if your team has been pressed for time, they are better off spending the time on driver practice, as @UnofficialForth suggested.
I wouldn’t say we did a great job painting and it still turned out to look way better than raw aluminum.
To answer the OP’s question… pretty much just paint it black.
It looks like your team did a decent paint job.
Runs in the paint and paint flaking off can look really bad**.
** Unless one is wanting the “rat rod” look.
The trick is not looking too closely at it 
Having a team/robot logo/name/number milled or engraved somewhere is really nice
Drape the bot in blue banners.
There is nothing worse than a painted robot with a rats nest for wiring.
Clean up and plan your wiring, not just for your bellypan, but for all electronics going on your mechanisms too. If you wire neatly, hide wiring in tubing, use ducting, zip ties, zip tie mounts, you’ll be in a good place.
I agree with all above, but there’s one thing they left out - aesthetically pleasing design.
After you figure out what your robot’s major functional lines but before you start any building, back up and look at those lines as a skeleton - where the pieces are, how they move. Then, figure out what aesthetics on top of that work for you, and include that in the design. Follow that concept through with your choices of colors and textures. [Added: @JameCH95’s post below has many great examples of this!]
And a few minor tidbits:
Use fine sandpaper or ScotchBrite to texture all your metal surfaces, especially those which you aren’t going to cover up. Using a power sander, it’s a lot quicker than paint or powder coat, and works well with many aesthetic types.
Sometimes even simple things like adding rivets where they aren’t needed (but complete the pattern set by those which are) can make a noticeable difference.
Real robots have curves!
The curve on the back of Feynman here was designed with a french curve. While subtle, it catches the eye.
Grace Hopper (our team’s name progenitor robot) was full of lovely curves on her side plates. They could have more easily been straight cuts. But lines are usually less sexy than curves.
Chuck had plenty of curves with offset and overlayed lightening patterns. It created a wonderful visual effect as he was viewed from different angles.
I specifically picked robots that 95 has made that were not painted, but painting is worth discussing along side this. We are huge fans of a quick shaker-can paintjob, just one coat, with a concise and planned color scheme. This takes good aesthetics to the next level.
Our 2017 robots, Wilbur and Orville, side-by-side show how aesthetics can be improved with a cohesive color scheme.
Instead of just painting everything one color (sorry #allblackeverything) picking different colors to highlight mechanisms or interesting shapes present in the design makes it pop. The unpainted practice robot looks more like a silver blob in comparison. However, you have to have those interesting shapes in your robot to start with!
To drive this point home, here is our 2018 competition and practice robots next to each other. The paint and cleaner wiring show off the robot well. While these robots have fewer interesting shapes than the others, we make the most of it by painting the chain maw red.
TL;DR - you should design in interesting shapes, even if it is a little harder, and make sure that these choices are cohesive. Coordinate your color scheme to highlight these interesting parts. Keep everything else clean. The clutter of wires, tubes, or poorly laid-out sponsors will detract from the robots aesthetic.
But don’t take my word for it. 118’s coordinated coloring has been wowing people since 2010. They contrast gold with white to highlight mechanisms and shapes on their robots to great effect.
I’m sure the special effect smoke and great lighting had nothing to do with it either : P
Consider using some of the virtual KoP from Inventables to get Lucite Light Guide acrylic. Toss it into an engraver and side light it with LED strips. Inexpensive and very cool looking. We did a joint project with one of our sponsors and used this as a front panel for our new pit carts.
TW
Ooooooh, interesting point, I would argue (for the sake of arguement) that:
Cool Looking =/= Aesthetically Pleasing
I’ve seen some cook looking robots with special under-glow an and other fancy tricks, but aren’t aesthetically pleasing. Either something is off feels off in the design, or it doesn’t seem to move “naturally” on the field. (Not to say a robot couldn’t be both, we are boarding some pretty subjective subjects)
Cool Looking - Something added in addition to the robot as an after thought
Aesthetically pleasing - Something that was thoughtfully incorporated in the design for a specific purpose along with the purposes of looking beautiful.
I’d love to hear other peoples thoughts on this idea!
Well, I can’t agree with those definitions.
By your definitions, this is Aesthetically Pleasing but not Cool Looking. By mine, it is Cool Looking but not Aesthetically Pleasing.
We could be getting into a generational thing here…eh?
Modern automotive styling (I’ll pick on cars, because they’re the closest thing there is to robots in this regard) apparently is really cool looking. But dang, are they ugly!
Yes, I’m 58 years old.
Not to derail the thread, but oml, modern sedans are just so uncool! I love the older style sedans that are a bit longer and boxier and much less this:
That being said, part of aesthetics and coolness is personal preference. @ADA1 build a robot that looks good to you and makes you feel good. The most important part of building a good looking robot is organization and planning. Also, a robot that is falling apart on the field will not look good, even if it is beautiful when standing still. FRC is a competition where “function over form” isn’t necessarily true, but it is certainly something to consider.
Teams 254, 696, 968, and 1538 all make beautiful robots. And its no mistake the mentors are all connected back in the day.
118 makes beautiful robots AND videos too.
Many other examples already shared.
Opinions on design trends (look in to the history of american product styling) will vary, but above all good design is timeless.
Style how you like, but design with elegance, design for your manufacturing capabilities. Curves or no, painted or bare: a dysfunctional robot is a ugly one.
In this context, I recommend a modernist form-directly-to-function approach. Team Dave does this well.
The overarching principle 2767 uses is what I’d like to term “deliberate design.” This is further broken down into the following points related to aesthetics:
