A New,On-Road,Continuously Operating,Emissions Remote Sensor.

摘要

Any vehicle traveling Southbound on Interstate 25 that exits towards downtown Denver on Southbound Speer Blvd.drives through the optical beam of an on-road,vehicle emissions remote sensor housed in a manhole.The emissions reading and a trigger signal from a vehicle sensor are fed to a micro-computer which waits for a corresponding trigger from a second vehicle sensor farther up the ramp,and displays the reading on an 8ft by 11ft variable message sign.The possible messages are GOOD,FAIR and POOR,triggered by <1%CO in the exhaust,>1% <3.5% and >3.5% respectively.GOOD readings in green LED are accompanied by a green smiley face on a cartoon car,FAIR in Orange get an Ooh! face and POOR in red get a frown.93% of the vehicles(which pass at about 10,000 per day)obtain a GOOD reading.These vehicles are responsible for about 30% of the mass emissions of CO at the measurement location.5% receive a FAIR reading and emit a further 30%,and the remaining 40% is emitted by the mere 2% of the vehicles receiving POOR readings.Independent evaluations indicate that as many as 4000 drivers may be motivated to repair their broken vehicles in a single year of operation.How the system works,how it is self-calibrating,and what the design considerations are for others contemplating a SMART SIGN will be discussed.