A low-cost coating health monitor (corrosion sensor) is being developed for Army ground vehicles. The
Coating Health Monitor or CHM is a battery-operated, wireless, miniature sensor system that uses electrochemical
impedance spectroscopy (EIS) to detect degradation of the chemical agent resistant coating
(CARC). It consists of a small electronics module together with a tape electrode that is mounted onto
the vehicle in areas prone to corrosion. The CHM performs a three-frequency EIS measurement to determine
the coating condition/protectiveness. Using a wireless handheld device or a stationary unit in a
drive-in bay, a motor pool soldier or similar inspector will periodically probe the CHM(s) on a vehicle to
monitor the health of the paint system. Critical sites on high-mobility, multiwheeled vehicles
(HMMWVs) and other ground vehicles have been identified that are subject to corrosion and are suitable
for the CHM. Different tape electrodes are being evaluated and their results compared to conventional
EIS for both solventborne and waterborne CARC coatings.