Laser Marking System Based on 3D CAD Model

In many cases of renovation work, it is very difficult to gain sufficient information about the existing building such as the positions and dimensions of the frame, interior and equipment because of incomplete or missing drawings. As a result, it is necessary to fabricate the parts on the construction site. We have been developing a system for measuring existing buildings precisely using a 3D laser scanner before renovation work, fabricating the parts in factories and assembling them on site. This system will increase productivity and eliminate construction waste. The system requires a function for positioning of the parts and marking precisely on the site. Our developed marking system determines positions from 3D-CAD data and indicates them with a motor-driven Total Station. The position data is produced from objects such as points and lines stored in a design file, and is saved as a marking data file. The Total Station reads the data file and marks the positions by laser automatically and precisely. This report describes the function to produce the position data file and to mark the positions with the Total Station. It also shows the results of a field test at an actual construction site. This research was carried out with a grant from the Ministry of Land, Infrastructure, Transport and Tourism.