Your example does not have an indirect object.

You would need to add to the sentence and say something like “Some robots wash dishes and floors for people”
In that example the indirect object is “people” and the objects are “dishes” and “floors”.

In English we often express the indirect object by preceding it with “for” or “to”. But this is not always the case, and word order can vary as in the following, where the indirect object is “them”.

1)We owe them our gratitude.
2)We owe our gratitude to them.
3)To them we owe our gratitude.

word order in (1) subject, verb, indirect object, object
(2) subject, verb, object, indirect object
(3) Indirect object, subject, verb, object

Isn’t it “Some robots wash dishes and floors”? If so:

Some robots: subject
wash:verb
dishes and floors: direct object

There is no indirect object.