Operator- RBA-01 Tommy

This also requires a bit of backstory.
Back in [I think] 2009, when I still did webcomics fairly frequently, I started one called Operator, which was intended to be a story of piloted giant robots in a WW1 setting. The choice of setting was more or less because 'Nazi mecha' has been done an awful lot, so I wanted to do German mecha that weren't Nazis. Unfortunately, I pretty much just barrelled into this without doing a whole lot of research first- my only source on WW1 being what I remembered from old History classes, and my only source on mecha being Gurren Lagann.
[Another tangent- piloted robots can usually be classified as 'Super Robots', or superheroic machines that have outright superpowers and break the laws of physics, and 'Real Robots', which are presented as more grounded weapons of war. Gurren Lagann was the former, Operator really should have been the latter.]
So Operator was kind of crappy in some respects, but it did form the basis of a consistent chronology in my head, which we'll be dipping in and out of in this blog. Fun! One thing that remains the same is that, in this chronology, extraterrestrial machines crash-landed on Earth some time in 1900, which gave us the technological boost to make working, piloted robots, named Armours. Posession of the alien machines increased international tension and contributed to the start of WW1 in 1914 [or, as it's known in this timeline, NE0014, NE standing for New Era]. Germany came up with a machine that could be operated by a single pilot and easily mass-produced, which Britain promptly stole, adapted, and produced as the RBA-01, nicknamed the Tommy.

The first iteration of the Tommy was sketched out very briefly beforehand [I assume] and mostly designed on the page due to laziness. This crop from a panel is honestly one of the best images I can find of the things. The basic proportions were inspired by Space Marine dreadnaughts. They were very chunky, and kind of rounded. One idea I liked from this first version was that the Tommy's 'head' was actually just a big helmet over the pilot's own head. This comic was lousy for scale, though, so there wasn't really room for a person to sit in there like that, much less move their arms [the Tommies worked on motion-capture-esque controls].

A year or so after Operator, I went back and re-designed all the mecha. They all gained wheels or treads of some kind on their feet. The Tommies lost the thing with the head I mentioned above, and the pilot sat in a cockpit in the big round torso [accessed via that brown hatch in front of the head]. The limbs became more skeletal, the arms in particular being just metal rods with plates attached. The engine was placed in a backpack with an exhaust pipe. They got better-looking machine guns and shields. I was thinking about restarting the comic, but that didn't happen.

For this design, I decided I'd actually look at WW1 'Mark 1' tanks in more detail, and blend those with elements I liked from the previous designs. In the process of reading up on them I discovered one very essential detail;

Mark 1 tanks were absolute shitholes to be inside of.

The previous Tommy design had an exhaust pipe because I naively assumed something with an engine would have a way for the exhaust fumes to get out. Nope, not the Mark 1. The crew shared one big internal space with the engine. It was noisy, hard to see, and full of fumes from the engine and guns. From this, I decided to eliminate things that made the Tommy safe or comfortable. Gone is the exhaust pipe, the torso block's shrunk so the engine's right behind the pilot's back, the hilariously unsafe feature whereby the pilot's head sticks out the top covered only by a helmet's returned, and the whole thing's a lot more angular. Mark 1 tanks were all flat panels of boilerplate and big rivets, pretty far from the Tommy's previously rounded armour. The skeletal arms remain, and the feet now have treads. To top it off, they're armed with the Mark 1's actual weapons.