Well, first of all – Oddy is a official Ship Engineer on a duty. He is not very “responsible” in a meaning, that Robot Barton use, but, well, he cares about ship. He will work hard to keep ship safe and he is very smart and qualified (and little lazy – but lazy in a “smart” way).
He likes to sleep and he likes to eat (especially sweets!) and that has influenced his figure a little bit. And he liked it long before he stuck in spaceship.
He hates routine work and always trying to think something to avoid this. And if he can’t, he can set aside that for long time, sometimes – for all eternity.
Years passing by on a lonely ship had influenced him. He became more sad, despite he is a really funny and loves to tell jokes.
And despite all problems with Barton – they are friends with that nerdy meticulous robot. There is no one alive here for long long millions of miles, except spacecraft team, but “where” or “when” or “which reality” they are – nobody knows.