3D tilt sensing by using accelerometer-based wireless sensor networks: Real case study: Application in the smart cities

Real-time tilt sensing in urban areas can provide crucial information regarding the instant evolution of sensitive assets of the city to better safeguard the sites sustainability and security of people. In this paper, we proposed a novel approach based on the accelerometer sensor to recognize tilt angle between the vertical plan (the light poles along the road, the transmission tower, crossing bridges, etc.) and the ground. Indeed, we used the tri-axial accelerometer embedded in a Wireless Sensor Network (WSN) platform manufactured by Libellium, named “Waspmote Starter Kit”. The collected data are sent from one sensor node to another until the gateway and then to the processing center. Our recognition method uses the calculation and mapping of the values sensed by an accelerometer to a corresponding angle. The z-component corresponding to the gravity allows recognizing the real-time tilt of the horizontal plane while the x and y-components indicate in which side the plan is bent. This approach is applied to the smart city to provide an effective solution for real-time electric transmission pole monitoring. A computer program processes the angle results of the mapping and plots the 3D scene on the monitoring screen reproducing the behaviour of electric pole remotely located. The experimental results of our approach are satisfactory because the average error that can be committed by comparing the calculated and measured angle is about 1.0.