Development of a Zigbee-based wireless sensor network of MEMS accelerometers for pavement monitoring

Safety related to pavement ageing is becoming a major issue, as cracks and holes in the road surface can lead to severe accidents. Although pavement maintenance is extremely costly, detecting a deterioration before its surface gets completely damaged remains a challenge. Current approaches still use wired sensors, which consume a lot of energy and are expensive; further than that, wired sensors may get damaged during installation. To avoid the use of cables, in this work a Zigbee-based wireless sensor network for pavement monitoring was developed and tested in the laboratory. The system consists of a slave sensor and a roadside unit: the slave sensor sends wireless acceleration data to the master, and the master saves the received acceleration data in a csv file. Further data or signal processing can be performed in the master based on this acceleration dataset. Two laboratory tests were carried out: the first one was to perform a dynamic calibration using a vibrating pot, and obtain the main characteristics of three micro electro-mechanical sensor (MEMS) accelerometers in terms of power consumption and sensitivity; the second one was to simulate the pavement response to a five-wheeled truck at different speeds by means of a vibrating table. Preliminary results showed that the Zigbee-based wireless sensor network of MEMS accelerometers is capable of capturing the required ranges of displacement/deformation, acceleration and frequency, ADXL354 becoming the best accelerometer with the lowest power consumption as small as 155 uA.