How could one realistically incorporate robots into a post-apocalyptic, 1930s setting?

Question

Trying to flesh-out a post-apocalyptic setting where humanity wiped themselves out during the late 1920s, early 1930s; The survivors have reverted to primitive practices while still having access to weapons and industrial machines from that time period.

It takes place on an abandoned mining colony, so there's lots of heavy mining and excavation machinery around; How would you justify having mining-robots (or automatons), that are able to take basic orders and use weapons without going into steampunk or superscience territory?

Answer 1

How would you justify having mining-robots (or automatons), that are able to take basic orders and use weapons without going into steampunk or superscience territory?

You can't.

The electronic in those years was based on vacuum tubes, good enough for a bulky radio, but not enough for a robot capable of doing what you are envisioning.

The simplest vacuum tube, the diode invented in 1904 by John Ambrose Fleming, contains only a heated electron-emitting cathode and an anode. Current can only flow in one direction through the device—from the cathode to the anode. Adding one or more control grids within the tube allows the current between the cathode and anode to be controlled by the voltage on the grid or grids. These devices became a key component of electronic circuits for the first half of the twentieth century.

Moreover, a mining environment is not exactly the most friendly place for a vacuum tube.

Answer 2

You want actual tech of the time. That leaves you with clockwork.

When I was a teenager I took apart an old adding machine. It had so many parts!

http://madrona.ca/e/mechCalc/RCAllen805/index.html

I use clockwork in the broad sense here - moving parts moved by mechanical energy that output a complex result, like the time or a sum. So too your automatons. They are complicated machines with many parts, powered by a mainspring and clockwork. Big ones might have been retrofitted with steam. In there 1920s there was electricity too but batteries were primitive, so an automaton powered by electricity might need a direct connection like a streetcar; or the electricity could be used to wind the spring.

A machine this complex is not going to dig a ditch or carry a rifle. Humans are cheap and good at stuff like that. But a giant drill might have a mechanical brain to aid it in its job and there might be other roles where, like an adding machine, mechanization offered advantages. I can imagine an ore sorter. You could have a mechanical security system that could have automated weapons.

These things are not going to chat you up like Commander Data. But it is amazing how far machines got with pure clockwork and moving parts.

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Shout out to Tik Tok, the clockwork man from Wizard of Oz (the books, not the movie).

Tik-Tok (sometimes spelled Tiktok) is a round-bodied mechanical man made of copper, that runs on clockwork springs which periodically need to be wound, like a wind-up toy or mechanical clock. He has separate windings for thought, action, and speech. Tik-Tok is unable to wind any of them up himself. When his works run down, he becomes frozen or mute or, for one memorable moment in The Road to Oz, continues to speak but utters gibberish.