This project developed a new type of self-de-icing LED signal for highway signalized intersections and railroad signaling applications to address the problem of existing LED signal lights with lens too cool to melt snow and deice in wintery conditions. The snow-clogged signal lights can decrease the performance of signalized intersections and railroads and may result in collisions in inclement weather conditions. The IDEA product was further field evaluated and refined in a pooled fund study involving seven states (Kansas, California, Michigan, New Jersey, Wisconsin, Pennsylvania, and Maryland). A total of five generations of prototypes of the self-de-icing LED signals (12 in.) in red, green, and yellow light colors were developed and their thermal and lighting performances were tested to meet all requirements to ensure their readiness for follow-up field tests. The prototypes were installed on pole-mounted signals as backup to the existing primary signals in Kansas, Wisconsin, and Michigan and their real-time performance was monitored and recorded by a remote field-monitoring system. The collected field data was used for real-time performance evaluation of the new signals for future implementation in practice by the project partners. Following the field tests and evaluation, pilot replacement programs will be needed in some of the pooled fund partner states. Once validated, the self-de-icing LED signals in various sizes are expected to be installed at highway intersections, Class I railroads, commuter railroads, and short-line railroads in cold weather zones. Two patents were granted for the innovation of “Heated Lens Lighting Arrangement” (Patent Nos. US 9,851,086 B2 and US 10,253,965 B2).  Another patent was issued for the innovation of “Integrated Light and Heat Arrangement of LEDs in Low Profile” (Patent No. US 10,215,441 B2). The research team is working with the University of Kansas Center for Technology Commercialization has been reaching out to the signal industry for patent licensing.  The developed LED signal light will not alter the function and sizes of the existing signal lights, and there will be no need to for additional wiring inside or outside of the existing signal controller cabinets, nor any need to change anything outside of the signal housing.

The final report is available.