Homemade Robot

Goals

The main goal of creating the robot was to create a hero asset to be one of the main focuses of one scene I’m currently working on in Unreal Engine 5.

In the beginning, it wasn’t supposed to be a separate portfolio post since the original idea was quite simple, a Roomba robot with some kind of electronic device and a LED attached to top of it.

References

After finding some cool references of various electronic devices that could fit into the robot I started to iterate adding more and more parts and, finally, I decided to use the robot as a practice to improve my design and composition skills and to refresh my prop workflow since I’m mostly working in-engine and doing environment work on my daily basis.

Here you can see the references I used for the robot parts and some other props from great artists I used as references for material definition or benchmark.

Software

• PureRef
• Maya
• Substance Painter
• Photoshop
• Marmoset Toolbag

Blockout & Design

To start with the robot creation I decided that I wanted to go for a realistic style but try to do it as “cute” as I could. I had in mind some charismatic robots like Wall-e and some others from the recent videogame Stray.

Also, I wanted to give it a homemade/custom look with a lot of cables, tapes, etc. For that kind of look, I used some references from Half-Lyfe: Alyx since they have really nice props with that style like the radio at the start of the game (I even used the same fan since I liked it for my design).

Since I was sure I wanted to use a vacuum cleaner robot as a base and cameras as eyes I started to figure out what assets I could use to make it look like it would work in real life (or at least being believable).

After some iterations, I ended up using one GoPro and a thermal vision camera I found on google for the eyes, a router on top of the head to give it more silhouette, one box like a CPU where you can connect everything together with cables, one antenna as a tail and some Li-Po batteries.

Since the design of the robot was not decided from the beginning my ref board changed a few times until the one you saw before in this article.

Also, I changed some of the components to match better proportions or just to improve the design or silhouette. For example, the antenna is made for FPV drones so I had to make the size bigger to match better with the other parts, also the Gopro is mirrored to avoid having the two lenses too close to each other.

Don’t be afraid of changing the design a few times and making iterations until you have something you like.

High Poly

From this part, my process was pretty much straightforward. I just modeled each part individually in Maya with the crease workflow.

I started with the blockout geometry as a base and before adding some extra edges for creasing I just duplicated the geometry to use it later in the lowpoly stage (this is also called mid poly, since with this geometry I will build both high and low models).

Modeling by creasing edges may be not the best way if you want to do hard surface and reiterate the geometry but is a very fast way to model highpolys.

Low Poly

For the lowpoly I just took each midpoly from the previous stage and optimized the geometry until I was happy with the result. In real production maybe I would expend more time optimizing but I for the portfolio is more than enough.

UVs

Nothing too fancy here, I just used Maya default UV tools and unwrapped my model, then set a texel density of 4k per meter for this project.
Again this texel is too high for production but for portfolio, you want as much as you can get.

I ended up using 2 UV sets with 1 set of textures each. One texture is 2048×2048 and includes almost all electronic devices and the other one is 4096×2048 mainly for the vacuum cleaner robot.

For those who don’t know you can create your UVs for a non-square texture like this:

Baking

For the bake, I used Marmoset Toolbag.

I like to explode my bakes to easily see all the parts separated and be able to change the cage or paint the skew without hiding and unhiding asses all the time.
Here you can see the lowpoly and highpoly overlapped ready to be exported for baking:

Texturing

After baking I imported the asset to Substance painter, and the first thing I like to do is add the normal map details that I didn’t create during the highpoly stage and add the fake holes on the model.

Then with the help of different references, I created all the base materials for plastic, metal, painted metal, etc.

Also added the labels, brand logos, etc that I created in photoshop as alphas. Some of them are done just using real pictures and applying levels to separate the logo from the background and others are done by hand in Photoshop.

The last step is adding the wear and tear, rust, dirt, and all other details.
I wanted the robot to look used and dirty but not completely destroyed and also wanted some parts to look better than others to give the feeling of being built from various non-related parts.

Here you can see the process of one part, but all of them are done in a similar way:

Render

For rendering I also used Marmoset Toolbag, I imported the asset with the textures and set up the materials to look right.

Also created some cameras, and light presets for different camera angles and placed a shadow catcher to add some volume. The lighting is just a studio sky from Marmoset with some extra lights depending on the render.

Final words

I recommend to everyone in any portfolio piece to ask for feedback. I did ask a few friends during the process and it helped a lot.

It also helps to stop working on the project for a few days to recover the perspective and see things clearly.

And as the last recommendation I suggest setting a deadline to finish your project. Creating a portfolio piece is sometimes tricky because you can just spend forever changing and tweaking things so I recommend you estimate time for every stage and set a deadline as you would do in a real production.

Thanks a lot to GamesArtist for contacting me to write this article and thank you for reading!