Retrieving value in controller - NoMethodError (undefined me

How can I retrieve the values in my controller for the text field
below? The “35” is the id of the item I want to update.

My controller is:

def update
@timesheet = Timesheet.find(params[:id])
@timesheet.timesheet_items.build(params[:timesheet_item])
@timesheet.update_attributes(params[:timesheet])
end