Some robots, including Uran in episode 30 "Uran and Uran", and Niki in episode 52 "Astro's first love" appear nude as they're going to be repaired or otherwise have a mechanical intervention. Their bodies are doll-like and featureless.

As is typical in vintage anime, there are plenty of upskirt shots of three young girl characters, especially Uran. It's usually played off as casual, but in one case Mindy shows embarassment and anger at being oggled at by a shrunken Alvin.

Throughout the series, there's a lot of violence among robots, with dismemberments being quite common. It can get quite brutal, but being machines there really isn't any gore to speak of.

At the start of episode 14 "Uran the Tomboy", Higeoyaji/ Daddy Walrus is comically drunk during a video call.

A lot of emotional moments.

Some of the antagonist robots are quite monstrous in design and behaviour, and might impress very sensitive children.