Nothing deliberate that I can think of, other than in Lemons when they deliberately returned to Red Dwarf from 1st century Earth. But I suppose that doesn't count. Trojan was possibly time-travel, because it is unclear (at least to me) if the Quantum Rod made Howard & Sim travel forward or the Dwarfers travel back. I suppose given it was aboard the Trojan it travelled the Trojan back. But I don't remember the Dwarfers ever travelling forward again (does that mean they're still in Howard & Sim's time?). I assume Howard & Sim came from the past because of Sim's wish to "start the uprising" against humans, but we don't actually know that. In any case, it was accidental.