/** Check if the vehicle class config should be updated */
 private boolean shouldUpdateClassConfig() {
   for (G4VehClass vc : G4VehClass.values()) {
     int dm = class_config.getClassLen(vc);
     int lb = vc.v_class.lower_bound.round(DECIMETERS);
     if (dm != lb) return true;
   }
   return false;
 }
 /** Update the vehicle class config bounds */
 private void updateClassConfig() {
   for (G4VehClass vc : G4VehClass.values()) {
     int lb = vc.v_class.lower_bound.round(DECIMETERS);
     class_config.setClassLen(vc, lb);
   }
 }