BIM-Based Multimodal Positioning Method and its Application

Positioning and navigation are commonly used technology services, however, in places such as bridge chambers, tunnels, underground spaces, indoor spaces where GNSS signals are unavailable, positioning and navigation becomes very difficult. In response to this special scenario, this paper proposes a positioning method which utilizes BIM models as a map scene and data source combined with multimodal inputs such as visual and auditory ones. This method encodes the position coordinates into QR codes and Chinese characters, and then locates them through QR code scanning, OCR, or voice recognition. Its advantages include simple, low cost, easy to deploy, and suitable for both indoors and outdoors, making it very good for positioning within environments lacking GNSS signal and/or power supply. Experiments show that this method can achieve accuracy from decimeters to centimeters, and can be used within geographic fences, AR perspectives, and other LBS applications.