Lane Departure Warning Systems for Commercial Vehicles

Lane departure warning systems (LDWS) and forward collision avoidance and mitigation systems (FCAM) collectively address approximately 20%-25% of the total heavy vehicle involved crashes in the United States (Kreeb, 2014).

Lane departure warning systems (LDWS) uses visual sensors to detect lane markers ahead of the vehicle to warn drivers of a lane departure when the vehicle is travelling above a specified speed threshold and the vehicle’s turn signal is not engaged to make an intended lane change or departure. LDWS also inform drivers when lane markings are insufficient for detection, or if the system malfunctions (Houser, 2009). LDWS systems may reduce the frequency of single vehicle roadway departure, lane change/merge, and rollover crashes involving large trucks.

Orban et al., (2006) conducted an independent evaluation of data from a 12-month long field operational test (FOT) involving 22 large trucks equipped with lane departure warning systems to determine the safety benefits of LDWS, as well as to ascertain user acceptance, human factors, and system performance. The results of the data analysis demonstrated that under the conditions of the field operation test, the use of LDWS could reduce driving conflicts associated with single vehicle road departures by 31% on straight roads and by 34% on curved roadways. In addition, the deployment of LDWS would reduce single vehicle roadway departures by 21%-23% and rollover crashes by 17%-24%. During the FOT, the LDWS was most effective in reducing lane departures at night and on straight roads at highway speeds. Driver acceptance, as determined by before and after driver surveys following use of the LDWS, was varied. Drivers felt that LDWS helped maintain alertness and reduce driver workload, but the warnings could be annoying and the false alarms caused a loss of confidence in the system. A benefit-cost analysis indicated that deploying and operating LDWS was economically justified for 10 of 16 vehicle scenarios, where benefit-cost ratios (BCR) exceeded 1. The scenarios involving tractor-trailers pulling tankers had BCRs ranging from 1.95 to 5.11, while all of the large trucks scenarios had BCRs below 1.

Nodine et al., (2011) evaluated the results of field operation tests that assess the safety impact, driver acceptance, and operational performance of an integrated vehicle-based safety systems (IVBSS) that included lane departure crash, rear-end, and lane-change/merge warning functions. The study involved 18 volunteer drivers from a commercial fleet who operated 10 equipped heavy trucks that travelled 600,000 miles over a 10-month period. Baseline information, where the LDWS system was disabled, was collected during the first two months of the study. The treatment period lasted for 8 months, where the system was enabled and warnings were issued to drivers. Feedback from drivers indicated that they found the system easy to learn and use. Most of the drivers (83%) indicated that they would prefer to drive a truck with the integrated system over a conventional unequipped truck. The integrated system increased driver awareness of traffic around them and the position of their vehicle in their travel lane. The authors of the study estimated that full deployment of integrated safety systems in the U.S. heavy vehicle fleet could prevent 2% to 11% of targeted crashes annually.

Houser et al., (2009) carried out a study to evaluate the costs and benefits for industry associated with lane departure warning systems. The authors of the study used the 2001-2005 average annual number of large truck lane departure crashes by crash outcome and severity to identify the target population that could benefit from this technology. The low and high estimates of targeted crashes that could be prevented with LDWS technology included 23% to 53% for single vehicle road departure collisions, 24% to 50% for single vehicle road departure rollovers, and 23% to 46% for same direction lane departure sideswipes, opposite direction lane departure sideswipes, and opposite direction lane departure head-ons. The authors of the study concluded that commercial vehicles fitted with this technology will likely see a net positive return on investment within a five-year product lifecycle for targeted crash types.

Kingsley (2009) analysed 1070 crashes from the Large Truck Crash Causation Study (LTCCS) database, which was compiled from 2001 to 2003, to estimate the size of real world crash populations that could be avoided using various crash avoidance countermeasures. She estimated that 6.1% of the crashes in the database could have been prevented if the commercial vehicles had been equipped with LDWS technology.

Hickman et al., (2013) carried out a retrospective effectiveness evaluation study of three frequently installed onboard safety system (OBSS) technologies, including lane departure warning systems. The crash data used for the analyses represented small, medium, and large carriers, but were skewed towards larger for-hire carriers. The data set included records of reportable crashes as well as minor incidents that occurred during the 2007-2009 period by the 14 carriers that participated in the study and travelled more than 13 billion miles. The study data were grouped into trucks equipped with OBSS and trucks without OBSS. Crash data were grouped into OBSS-related and not OBSS-related. The results of the study indicated that 2.7% of the crashes could have been mitigated or prevented by LSWS. The study also demonstrated that trucks with LDWS had an LDW-related crash rate that was significantly lower per million vehicle miles travelled than the rate for trucks without LDWS. In addition, the benefit-cost analysis demonstrated that the estimated benefits of LDWS technology deployed at participating fleets outweighed the estimated costs.

Research has shown that equipping commercial vehicles with lane departure warning systems is effective at preventing LDWS-related crashes and is economically justified. For some time, the Federal Motor Carrier Safety Administration in the United States has promoted the voluntary adoption of these systems within commercial vehicle fleets and has worked closely with the trucking industry to define vendor-independent voluntary requirements (Houser et al., 2005). More recently, Hoover et al., (2014) compared domestic and international standard test procedures and evaluated a developed test procedure for heavy-vehicle lane departure warning systems.

Scope of Problem:

• Kreeb, R. (2014). NHTSA Heavy Vehicle Crash Avoidance Research Overview. SAE Government Industry Meeting: January 2014, Washington, D.C. Retrieved from: www.nhtsa.gov/DOT/NHTSA/NVS/Public Meetings/SAE/2014/Kreeb S… · PDF
• Houser, A. (2009). Tech Brief: Benefit-Cost Analyses of Onboard Safety Systems. Publication No. FMCSA-RTT-09-023. Federal Motor Carrier Safety Administration, Washington, D.C. Retrieved from: http://www.mobileye.com/wp-content/uploads/2011/09/OnboardSafetySystems-FMCSA.pdf

Evidence:

• Houser, A., Murray, D., Shackelford, S., Kreeb, R., & Dunn, T. (2009). Analysis of Benefits and Costs of Lane Departure Warning Systems for the Trucking Industry. Report No. FMCSA-RRT-09-022. Federal Motor Carrier Safety Administration, Washington, D.C. Retrieved from: http://ntl.bts.gov/lib/51000/51200/51250/09-022-RP-Lane-Departure.pdf
• Kingsley, K. J. (2009). Evaluating Crash Avoidance Countermeasures Using Data from FMCSA/NHTSA’s Large Truck Crash Causation Study. Proceedings of the 21st International Technical Conference of the Enhanced Safety of Vehicles, Stuttgart, Germany, 2009. Retrieved from: http://www-nrd.nhtsa.dot.gov/pdf/esv/esv21/09-0460.pdf
• Hickman, J.S., Guo, F., Camden, M.C., Medina, A., Hanowski, R.J., & Mabry E. (2013). Onboard Safety Systems Effectiveness Evaluation Final Report. Report No. FMCSA-RRT-12-012. Department of Transportation, Federal Motor Carrier Safety Administration, Washington, D.C. Retrieved from: http://ntl.bts.gov/lib/51000/51200/51256/12-012_OBSS_Report.pdf
• Orban, J., Hadens, J., Stark, G., & Brown, V. (2006). Evaluation of the Mack Intelligent Vehicle Initiative Field Operational Test, Final Report. Report No. FMCSA-06-016. Department of Transportation, Federal Motor Carrier Safety Administration, Washington, D.C. Retrieved from: http://ntl.bts.gov/lib/51000/51200/51298/Evaluation-of-the-Mack-Intelligent-Vehicle-Field-Operational-Test-Sep2006.pdf
• Nodine, E., Lam, A., Wassim, N., Wilson, B., & Brewer, J. (2011). Integrated Vehicle-Based Safety Systems Heavy-Truck Field Operational Test Independent Evaluation. Report No. DOT HS 811 464. U.S. Department of Transportation, National Highway Traffic Safety Administration. Retrieved from: http://www.nhtsa.gov/DOT/NHTSA/NVS/Crash%20Avoidance/Technical%20Publications/2011/811464.pdf
• Hoover, R.L., Rao, S.J., Howe, G. & Barickman, F.S. (2014). Heavy-Vehicle Lane Departure Warning Test Development. Report No. DOT HS 812 078. National Highway Traffic Safety Administration Vehicle Research and Test Center, East Liberty, OH. Retrieved from: www.nhtsa.gov/DOT/.../812078_Heavy-VehicleLaneDepartWarnTestDevelmt.pdf.
• Houser, A., Pierowicz, J., & Fuglewicz, D. (2005). Concept of Operations and Voluntary Operational Requirements for Lane Departure Warning System (LDWS) On-board Commercial Motor Vehicles. Report No. FMCSA-MCRR-05-005, Federal Motor Carrier Safety Administration Office of Research and Analysis, Washington, DC. Retrieved from: http://www.todaystrucking.com/images/lane-departure-warning-systems.pdf