Why is Logan sometimes in a wheelchair but not always?

Question

Seriously, there's probbably a really simple explanation that I should actually know, but i don't so someone please tell me.

Yeah, sorry, i messed up the question and posted it in two parts, i am talking about dark angel. Ok glad that's been made clearer.

Answer 1

Do you mean Logan from the sci-fi series "Dark Angel", well he could walk, then had an accident so ended up in a wheelchair, then he got hold of a special device that he clamped to his legs enabling him to stand upright and walk (kinda like Robocop) , apologies now if you are talking about someone/something else!

Answer 2

Logan who? :)