Development of Automatic Road Marking Removing Equipment Using High Pressure Water-Jet

Present removal work for road markings has been time-consuming and labor intensive because it has been performed manually using shaving type equipment. The traditional process causes traffic delay due to the passing control, resulting in unexpected accidents to workers working at dangerous road circumstance. Besides, the current shaving method leads to air pollution as well as explosive accidents caused by propane gas. Thus, we have studied to develop the automatic removing equipment which consists of a high pressure water-jet system, automatic control system and mobile system: the water-jet system consists of an intensifier and nozzles to give a high pressure and spray on the marking; the automatic control system is composed of one axis robot using a hydraulic servo actuator controlled by a lever; and the mobile system employs a truck which plays an important role for transport of equipment and forward movement in a removal process. In this paper, we have analyzed the characteristics of road markings and investigated current removing methods in this field. In addition, we have organized and designed automatic removing equipment. We have also made a basic experiment to find out the optimized spray condition such as spray distance, spray angle and injection pressure.