In construction site, many of building materials and structural members are moved and positioned by the crane operator. Due to the limitation of eyesight of a crane operator, it is not possible to place the precise position. Especially, nowadays, PC construction and prefabricated construction need a precise positioning system to reduce construction time and increase construction accuracy [1]. Vision-based 6-DOF estimation system can provide the relative position between two construction members in real time. Since the sizes of general construction members are normally more than 3m, displacement information about only one spot is not enough as the linear error is proportional to the distance from where the angular error occurs. Therefore, the multiple vision sensor approach will be effective to estimate an overall displacement of large construction member. One module consist of pair of camera and planar marker. We assume that this system will be applied for PC slab construction or replacement construction for repair. Two cameras are installed in the shear pockets on both ends of the PC slab whose width is about 10 m and the corresponding markers to cameras are installed the support beam where PC slab is supposed to be placed. Each datum from each sensor module will be transmitted to main computer using wireless technology and fused by Monte Carlo Localization (MCL) algorithm by which optimal pose information is estimated.
doi: 10.12783/SHM2015/53