Automated Commercial Vehicle Screening
By Don Loud, OIT
At some point in the past, you have most likely read or heard in the news of some horrific highway accident involving tractor trailers. The Commercial Vehicle Enforcement Unit, a division of the Maine Department of Public Safety, is charged with preventing such accidents by enforcing state and federal safety standards. Additionally, the officers are responsible for enforcing highway weight limits as well as ensuring that carrier and driver insurance status, tax status, license and registrations are current and valid. Much of this enforcement activity takes place at inspection sites such as the Kittery weigh station.
Given that, on average, 250 commercial vehicles per hour pass the Kittery weigh station during a normal day, this responsibility sounds like an overwhelming challenge. Now consider that, previously there was no central repository for the information needed to enforce the state and federal safety, weight and credential standards. Because of the high volume and lack of screening tools, the selection of commercial vehicles for inspection was hit or miss. Prior to this year, the officers staffing the weigh station selected vehicles for inspection based on memory of past violations and appearance of the vehicle. Once the vehicle was pulled aside for inspection, they had to query several databases for all the pertinent enforcement information.
The Automated Commercial Vehicle Screening System (ACVSS) is designed to assist the officers by automating the screening process. Now, with ACVSS, when the Kittery weigh station is “open,” trucks exit the turnpike and are immediately weighed when they pass over a weigh-in-motion scale on the ramp. This scale has an accuracy of approximately 98 per cent. Next, a picture of the vehicle is taken and an Optical Character Reader (OCR) captures the DOT registration number and license plate number. These numbers are queried against a data warehouse (developed in a sister project) to determine credential status (safety, insurance and tax). Based on weight and screening of credential data, a lane indicator is turned on within 10 seconds of passing the weigh–in- motion scale. If there are no weight or credential violations, the vehicle gets a green arrow to enter the bypass lane and immediately returns to the turnpike. There are sensors in the ramp pavement to ensure that trucks stay in their designated lanes. If the weight is over limit or there is a credential violation, the vehicle gets a lane indicator to pull onto the static scale where weight and credentials are checked. If warranted additional inspection is performed in the parking area.
The officers in the scale house monitor the vehicles as they pass through the weigh station on a large monitor which has a graphical user interface (GUI) display map of the weigh station which shows the movement of the vehicles as they pass through the station. Additionally, they have several closed circuit television (CCTV) cameras which provide real time streaming video of various areas of the weigh station.
As you may suspect, truckers sometime try to avoid the weigh stations by taking an alternate route. It just so happens that US Route 1 and State Route 236 are favorite bypass routes for truckers when the weigh station is open. To catch such instances, sensors have been placed in the pavement and cameras have been installed on those two routes. When the station is open, these two routes are automatically monitored by the system. When an overweight vehicle passes over the sensors a picture is taken and weight data is passed to a second monitor at the weight station. In the event the officers do not see the image appear on the monitor, a female voice informs them that “A bypass violation has occurred.” The officer at the weigh station then determines whether or not to dispatch an officer to intercept the violator.
An open house at this facility is planned for later this spring.