DEF time TimeSensor { cycleInterval 10 loop TRUE enabled TRUE }
  DEF rotation OrientationInterpolator {
  key [ 0 0.25 0.5 0.75 1 ]
  keyValue [ 1 1 0 0, 1 1 0 1.57, 1 1 0 3.14
             1 1 0 4.71, 1 1 0 0 
           ]
  }
  
  
  
  
  ROUTE time.fraction TO rotation.fraction
  ROUTE rotation.value TO object.rotation