Lane Departure Warning (LDW) Systems Minimum Performance Requirements
The specification will provide objective criteria for acceptance of the test procedures given SAE J3045-1, of the LDWS (e.g., ability to detect lane presence, and ability to detect an unintended lane departure), its ability to indicate LDWS engagement, its ability to indicate LDWS disengagement, and determine the point at which the LDWS notifies the Human Machine Interface (HMI) or vehicle control system that a lane departure event is detected. The HMI is not addressed herein, but is considered in SAE Standard J2808.
Rationale: Several efforts are underway by agencies both US and international, to specify, recommend, or codify LDW systems in passenger car and truck, whether it be their functions, operational characteristics, or performance.
The primary objective of the SAE Active Safety Systems’ Lane Departure Task Force is to merge the substance and ideals from existing standards, regulations, and known test methods into a concise test procedure which will be used to verify basic LDW system operation. A detailed test procedure has now been developed and approved by ballot as SAE J3045_201507 “Truck and Bus Lane Departure Warning Systems Test Procedure”. The rationale in creating this test procedure which uses common methods in agreed operating conditions for application to certain test vehicles was: “With the commercial availability of various Lane Departure Warning Systems (LDWS) and limited existing standards and regulations for trucks and buses greater than 10,000 lbs. GVW, a vehicle test procedure (T.P.) of common methods to evaluate the effectiveness of these systems is justified.” The SAE Active Safety Systems committee furthered this objective with the approval of the Truck and Bus council. The test procedure satisfied its justification as stated in the rationale that the objective was an agreement of common methods in various “Lane Departure Warning Systems where there are limited existing standards and regulations”.
The next objective of the SAE Active Safety Systems committee is to create a complement of the J3045 test procedure to establish minimum performance requirements associated with the LDW systems.
The Motor Vehicle Council has set the bar stating: “Performance specifications must be fully justified in the rationale accompanying the Technical Report …. This means there must be good, publicly-available evidence that complying with the specifications will ensure that a well-defined function will be fulfilled and non-compliance will not fulfill that function.” Similarly, the Truck and Bus Council requires similar justification and scope before it will endorse a Work in Progress activity for LDW systems.
The following existing passenger car, heavy truck, and bus standards are referenced in SAE J3045.
• FMCSA-MCRR-05-005 “Concept of Operations and Voluntary Operational Requirements for Lane Departure Warning System (LDWS) On-board Commercial Motor Vehicles”
• NHTSA: “Lane Departure Warning System Confirmation Test and Lane Keeping Support Performance Documentation, February 2013. (LDW_LKS_2-7-2013.pdf).
• EC 351/2012:“Implementing Regulation (EC) No 661/2009 of the European Parliament and of the Council as regards type-approval requirements for the installation of lane departure warning systems in motor vehicles.”
• ISO 17361:“Intelligent transport systems - Lane departure warning systems - performance requirements and test procedures”
It could be argued that the since the rationale for creating the SAE J3045 LDW test procedure was for an agreement of common methods, then the rationale can be justified for creating LDW minimum performance requirements is for an agreement of common acceptance criteria of the test procedure results.