  Large indoor spaces have complex layouts making them difficult to navigate.
Indoor spaces in hospitals, universities, shopping complexes, etc., carry
multi-modal information in the form of text and symbols. Hence, it is difficult
for Blind and Visually Impaired (BVI) people to independently navigate such
spaces. Indoor environments are usually GPS-denied; therefore, Bluetooth-based,
WiFi-based, or Range-based methods are used for localization. These methods
have high setup costs, lesser accuracy, and sometimes need special sensing
equipment. We propose a Visual Assist (VA) system for the indoor navigation of
BVI individuals using visual Fiducial markers for localization.
State-of-the-art (SOTA) approaches for visual localization using Fiducial
markers use fixed cameras having a narrow field of view. These approaches stop
tracking the markers when they are out of sight. We employ a Pan-Tilt
turret-mounted camera which enhances the field of view to 360{\deg} for
enhanced marker tracking. We, therefore, need fewer markers for mapping and
navigation. The efficacy of the proposed VA system is measured on three
metrics, i.e., RMSE (Root Mean Square Error), ADNN (Average Distance to Nearest
Neighbours), and ATE (Absolute Trajectory Error). Our system outperforms
Hector-SLAM, ORB-SLAM3, and UcoSLAM. The proposed system achieves localization
accuracy within $\pm8cm$ compared to $\pm12cm$ and $\pm10cm$ for ORB-SLAM3 and
UcoSLAM, respectively.
