sliding mode controller design

my system is fifth order, but transfer function shows upto powers of s^2 only ....Is the system controllabe...also help me design a PID controller using SISOTOOL..

[Arkadiy Turevskiy]

http://www.mathworks.com/matlabcentral/answers/6200-tutorial-how-to-ask-a-question-on-answers-and-get-a-fast-answer