01589878

Monograph

http://www.trb.org/Main/Blurbs/173641.aspx

This project focuses on the development of a new generation battery-less wireless weigh-in-motion (WIM) sensor. The WIM sensor utilizes a previously-developed energy harvesting system. As each axle of a vehicle travels over the sensor location in the road, vibrations are induced in the sensor and energy is harvested from these vibrations to power both sensor operation and wireless transmission. Major shortcomings in the previous WIM sensor included the use of a baler belt top for the sensor and inability to grout the sensor for permanent installation in pavement. These shortcomings are addressed in this project by developing an all-metal design that encloses the electronics of the sensor. A smart phone app is developed that allows internet access to the weight measurements from the sensor. The performance of the sensor is evaluated at a test pavement facility. A number of test vehicles are used to evaluate the performance of the system. The WIM system provides weight measurements that increase monotonically with increasing axle weights. However, significant variability is found from one test to another for the same vehicles and same axle loads. The variability is diagnosed to be due to the sensor enclosure box, which provides variability in load depending on the lateral position of the vehicle in the lane. A new WIM sensor is then designed, fabricated and evaluated that is based on measurements of strain in the enclosure box itself. The new sensing system provides better performance that reduces measured weight variability by more than 50%. However, there is no easy path to integrate the new design with a battery-less wireless energy harvesting system. The research team recommends that the second year of the project be abandoned, since the sensor developed in year 1 did not provide adequately satisfactory performance.

This NCHRP-IDEA investigation was conducted by the University of Minnesota.

Highway IDEA Project 165

English

36p

2013-12

NCHRP-IDEA Program Project Final Report

Final Report

Print

Figures; References; Tables

Product development; Prototype tests; Sensors; Weigh in motion; Wireless communication systems

Innovations Deserving Exploratory Analysis (IDEA) (Program)

Highways; Vehicles and Equipment; I30: Materials

TRIS, TRB, ATRI

Feb 5 2016 2:28PM