Passive Sensing of Electrically Conductive Concrete for Lateral Vehicle Positioning

Abstract

Autonomous vehicles (AV) offer multiple safety benefits for drivers and road agencies. Current AV technology allow for vehicle control, guidance, and navigation as well as communication with other vehicles and roadside infrastructure. To see significant penetration of Level 4 or 5 AV without compromising safety, redundant vehicle to infrastructure sensing capabilities are necessary especially during severe weather conditions. Existing vehicle technology is not able to communicate with the concrete and asphalt pavements without embedded sensors. An eddy current technique is proposed that detects local changes in the concrete's electrical conductance so that AV can determine their lateral lane position. Concrete slab specimens with varying dimensions and dosages of steel-fiber reinforced concrete (SFRC) were tested under normal and adverse surface conditions (standing water or ice) as well as separation distance from the transmitter coil. The longitudinal segment of SFRC's material was successfully located as the coil moved laterally across the surface even under these adverse surface conditions. This pilot study demonstrates a reliable and robust technique using changes in the concrete's electrical conductance to provide lateral positioning redundancy to AV control and guidance.