Looking for name of fantasy trilogy published abouot 15 years ago,?

Question:

Looking for name of fantasy trilogy published abouot 15 years ago,?

I believe it was a triology pubished probably 15 years ago.
I do not remember much about it. It was set in the future a space fantasy that involved a long lost prince or king who was trying to get a sword that only members of the royal family could use. When you picked up the sword, little spike came out that injected everyone with something(nanobots?) that would kill everyone but people with the royal bloodline. There was also a robot that was some what of a smart a**.

One of the only parts of the book I remember, there was a gun fight at a space dock and one of the lead characters handed the king or prince aspirin as a pain reliver because they were out of everything else.

I know that is not much to go one, and me memory is sporadic at best, but any ideas would be appreciated....

Thank you.

Best Answer - Chosen by Asker: Sounds like a mixture of King Arthur and Star Wars. Here are some ideas.

The Barrytown Trilogy (1987-1991) by Roddy Doyle
The Deptford Trilogy, The Cornish Trilogy, The Salterton Trilogy by Robertson Davies
His Dark Materials (1995 - 2000) trilogy by Philip Pullman
The Mars trilogy (1992-96) by Kim Stanley Robinson
The Regeneration trilogy (1990-1995) by Pat Barker
The Sprawl trilogy (1984-88) by William Gibson
The Sword of Honour (1952-1968) trilogy by Evelyn Waugh
To the Ends of the Earth (1980-1989) trilogy by William Golding