URL issue in rails routing

URL issue in rails routing

I have a link as below
<%= link_to member.full_name,{:controller => "reports",:action =>
"student_details", :stud_id =>
member.id,:vehicle_id=>@vehicle,:type=>@type,:month=>@start_date,:category=>@category
} %>
In the routes.rb I have defined as
map.connect "/reports/student_details", :controller =>
reports',:action => 'student_details'
But when I click this link and go to the page, the url is showing as
complete url with all the params appended in the link.. I want the url to
be shortened like, reports/student_details/id How do I do that.. Please
help..