The automation of quantity measurement for building services projects

Abstract

Throughout the revolution of Computer Aided Design (CAD), computerized taking off methodologies including object-based models, digitised models and non object-based automated model have gradually emerged and become commercialised. However, quantity surveying consultants and contractors in Hong Kong still prefer the traditional manual approach. As identified, fragmented CAD draughting convention is the main barrier to achieving practical automated solutions. Under a Teaching Company Scheme of the Hong Kong Polytechnic University and Chubb Hong Kong Limited, this research advances the non object-based automated model and adopts the new international CAD draughting standard, i.e. ISO 13567. The proposed model comprises a Layer Management Prototype (LAMP), a Block Insertion Prototype (BIP) and a Computer-Aided Measurement Prototype (CAMP). In line with the Teaching Company, the modules for fire services systems have been built with possible extensions to other services at a later stage. The prototypes were evaluated in HACTL SuperTerminal 1 at Chek Lap Kok New Airport. Besides, structured demonstrations were held for sharing and exchanging knowledge, as well as getting feedback from the participants. The results indicate that CAMP was on average 10 times faster than the manual approach. It achieved up to 99% measurement accuracy for a correctly structured CAD drawing. Nevertheless, the time saved in measurement was not enough to cover the extra CAD operation time in standardisation. The author proposed some artificial intelligent functions for improvement. However, there are still a number of restrictions imposed on this model. Further research efforts are of vital importance.