Does Astro have saliva or other lubricants for his body?

[diehard67]

I have no idea how tenma designed him but if it were me, I would have ran tubes caring oil to and from the joints, run it threw some filters and a pump.

this would keep the joints lubricated and can also serve as a coolant, hot oil could be directed to a heat exchanger under his skin and simulate body heat.

[fafner]

Or use ball bearing. It would still need to be replaced from time to time, but it would certainly be less often and less difficult to manage than lubricants.

[diehard67]

they still need to be lubed, and changing oil if circulated is a lot easer then takeing him all apart to change bearings or re grease em.

[Dragonrider1227]

Well, it's kind of established that he can cry. They say he has artificial tears. I assumed the sweating was sort of a symbolic thing. Not literally doing it, but showing it to express his emotion

[Fauna]

Could that GIF feature just condensation on him? I've seen shows like Key the Metal Idol where the main character gets left on the apartment porch and dew forms on her. Although with that Astro image, a lab typically isn't humid enough to do that to something.

He's cried in the manga, I remember, and maybe some sweat but that was more for a gag look where a few drops are flying off him. When I was a kid, I thought he had a special inner tank that would have to be occasionally refilled so it could provide tears or sweat for certain commanded emotions.

[jeffbert]

Both tears and sweat are used to show emotion; I have seen him panting, as though out of breath. All the same thing, used to show emotion.

The discussion itself seems to be rather geeky; I recall COMIC BOOK GUY arguing about some super hero with someone, & the whole thing was funny because these guys took the stuff much too seriously.

Some here are analyzing this a bit too much. Though if I had created a robot child, I would want him to be as close to real as possible. I would use a circulatory system to both cool the CPU & make the skin warm. Though, on the other hand, it might be a bit expensive or impractical. A nice mechanical multi-speed 4 chamber heart that pumps the coolant around would be coupled to an impeller driven system that keeps the coolant constantly flowing over the CPU. The former to make him seem 'real' while the latter keeps him from burning up. Respiration may also help cool him. But that stuff is complex!