Over the road truckers have a lot to worry about.
Their prime concern has always been to deliver goods on time, of course, but today’s drivers face many new challenges, including increased demand for freight transportation coupled with a growing commercial driver shortage and unpredictable drive times from main trunk lines to distribution centers, among others.
The Florida Department of Transportation (FDOT), in partnership with the University of Florida Transportation Institute (UFTI), recently conducted a research project aimed at reducing commercial driver stress over another difficulty they face, something most of us take for granted – finding a safe place to park.
Federal rules regulate the number of hours that truck drivers can be on the road in a given stretch of time and establish mandatory periods of rest between shifts. More recent legislation and electronic logging devices make it possible to track driver time-on-road closely. This is for driver health and safety, but also means that truckers must be strategic about where they pull over to take their break.
“If a driver is nearing the end of his shift, pulls in to a rest stop, and finds it full, he has to get back on the road to find another, which can put him over his time limit,” said Marie Tucker, FDOT Commercial Vehicle Operations Manager and Project Manager for the research study. “Driving over time limits incurs penalties, so not knowing where available parking spots are is a significant source of anxiety for truckers.”
It would be ideal for commercial drivers to know which rest stops had open parking spots before leaving the highway so they could drive by full ones without slowing down. Fortunately, there are new sensor technologies on the market that can monitor parking spots and, in theory, let drivers know if and how many open spots there are in a nearby rest stop, before driving in. This research study evaluated three of them for accuracy.
“The idea of these sensors has great promise,” said Dr. Scott Washburn, Professor of Civil and Coastal Engineering at UFTI, and Principal Investigator for the study. “But there are many factors that can influence the detectors, so we needed a field test.”
The research began with a review of possible vendors to identify technologies that would fit this application.
“After our review, we narrowed the list down to five possible vendors,” Washburn said. “We contacted all five, and three told us that the development of their equipment was advanced enough for testing.”
To field test the sensors, the research team chose two rest stops on Interstate 75 in Columbia County with commercial truck parking spaces, one northbound and one southbound.
Each of the three sensor companies was allotted ten parking spaces for installation and testing of their technologies, two on the northbound side and one on the southbound. Two of the technologies had similar operating frequencies, so they were located on opposite sides of the Interstate.
As the sensors were installed, the research team evaluated them for ease and timeliness of installation.
“It would not be helpful to us if installing the sensors was overly costly or complicated, even if they worked well,” Tucker said.
All three sensor types met the criteria for efficient installation.
“All vendors installed the sensors and other relevant equipment in their ten spots within two to three days,” Washburn said. “And they were all installed without costly or specialized tools.”
After installation and before testing began, each vendor spent 1-2 weeks tuning and calibrating their systems.
Truth on the Ground
To ground-truth the data from the sensors, the research team installed video cameras on light poles at each location to monitor the test parking spots visually. The video would be used to verify the accuracy of each technology, matching the data from the sensors to time stamps on the video.
“Each of the vendors said their technology can detect open and taken spots with a high degree of accuracy and in diverse weather conditions,” Washburn said. “The video provided us with indisputable evidence to make sure.”
After all of the sensors and video equipment were installed and calibrated, data collection commenced. Each location was monitored for several weeks.
Analysis of the data started by reducing the many hours of video taken at the test sites to usable information. The ingress and egress of each vehicle were painstakingly recorded manually from the video footage and then entered into CSV-formatted files for further analysis. The following information was logged for each entering/exiting truck over the test period:
- Parking space number
- Time entered the space
- Time exited the space
- Vehicle type (i.e., truck with/without trailer and trailer type, single unit truck, RV, personal car, etc.)
The research team also developed an analysis software tool to process and analyze the data. The CSV-formatted files were then loaded into the software to compare with the data from the in-ground sensors.
Parking with Precision
With the data in a manageable form, the team developed two accuracy tests to evaluate the parking detection technologies: turnover accuracy and occupancy accuracy. The turnover accuracy test evaluated the sensors’ ability to identify parking events (ingress and egress) correctly. The occupancy accuracy test evaluated the percentage of time that the sensors reported the status of the parking spaces (vacant or occupied) correctly.
Overall, all three sensor technologies performed quite well in both accuracy tests. Turnover accuracy ranged from 95.25 percent to 97.94 percent and occupancy accuracy ranged from 97.20 percent to 99.15 percent.
“We were very pleased with the results,” Washburn said. “Basically, it appears that any of the technologies we tested would be cost-effective and accurate.”
Integration with SunGuide®
For any parking detection technology to be truly useful, the information it gathers about open spaces must be delivered to truckers in a way they can use it. Therefore, one criteria for any sensor is that the data it gathers should integrate with the Florida SunGuide® software that is used by all regional transportation management centers across the state.
“If the information from the sensors can be gathered by SunGuide®, then it can be pushed out through the Florida 511 system and dynamic messaging signs,” Tucker said. “It can even be included in commercial navigation applications.”
This would give truckers the status of parking spaces easily in real time, letting them pull over with more confidence and removing one of the pressures they face on the road.
All the vendors involved in the testing say their sensors can integrate with SunGuide®. However, this has not yet been independently verified as it was not in the scope of this project.
The Future of Commercial Parking
Now that these technologies have proven effective, Tucker and her team are moving to broaden their use.
“Based on the results of this research, FDOT created a developmental specification for the in-ground detection technology that was tested,” Tucker said. “The approved vendors are now on our innovative products list for all to use.”