The publication of United Nations Economic Commission for Europe (UN ECE) Regulation No. 157.00 on automated lane keeping systems (ALKS) in March 2021 represented a major milestone in the establishment of the legal requirements necessary to allow for the type approval of fully automated vehicles. However, this initial version of UN ECE Regulation No. 157 was just a first step in the development of the legal requirements on automated driving systems.
As soon as drafting work on the original version of ECE 157.00 was complete, proposals to update and expand the content of the Regulation were submitted to the UN ECE Working Party on Automated/Autonomous and Connected Vehicles (GRVA) for consideration. One of these proposals was to increase the maximum speed at which automated lane keeping systems (ALKS) can operate from 60km/h to 130km/h. Another proposal was to expand the Regulation to cover ALKS that incorporate a lane change capability, i.e. where the system can execute a lane change manoeuvre without input from the driver.
Due to the complexity and magnitude of the work involved in updating ECE 157.00 to address these two proposals, a Special Interest Group (SIG) was set up to undertake this work. Between January 2021 and May 2022, this SIG met 15 times, and the results of their work were published as an 01 Series of Amendments to UN ECE Regulation No. 157 on March 3, 2023.
With regard to the lane change capability of automated lane keeping systems, the 01 Series of Amendments to ECE 157 specifies the following situations where an ALKS with lane change capability may intentionally cause the vehicle to cross a lane marking:
- As part of a "regular"lane change, e.g. to overtake a slower moving vehicle or where the lane in which the vehicle is currently travelling is closed or blocked.
- As part of a "minimum risk manoeuvre"(MRM). A minimum risk manoeuvre is initiated when there is a severe vehicle or system failure and it is necessary to bring the vehicle to a halt in a controlled manner.
- As part of an "emergency manoeuvre"(EM). An emergency manoeuvre is initiated when an imminent collision risk is identified. The emergency manoeuvre, which may include an evasive lane change, is intended to avoid or mitigate such a collision.
- To form an access corridor for emergency/enforcement vehicles in accordance with national traffic rules.
- To avoid an obstacle which is partially blocking the lane in which the vehicle is travelling. In instances where a full lane change is not possible, a partial excursion into an adjacent lane is permitted.
Detailed requirements on the function and performance of the lane change capability of automated lane keeping systems are introduced by the 01 Series of Amendments to ECE 157, including minimum forward, lateral and rearward detection ranges that the sensing system must be able to achieve. The 01 Series of Amendments also introduces a large number to new test scenarios to assess the functionality and performance of the lane change capability of the ALKS.
With regard to the maximum speed at which the ALKS can operate, the 01 Series of Amendments to ECE 157 increases this speed from 60km/h to 130km/h. However, only automated lane keeping systems which incorporate lane change capability are permitted to operate at speeds in excess of 60km/h.
Additional requirements on the function and performance of automated lane keeping systems capable of operating at speeds in excess of 60km/h are introduced by the 01 Series of Amendments to ECE 157, including an increase in the minimum forward detection range that the sensing system must be able to achieve. The 01 Series of Amendments also introduces a number to new test scenarios to verify the functionality and performance of the ALKS at speeds in excess of 60km/h.
With regard to introduction dates, the transitional provisions contained in ECE 157.01 specify that compliance will become mandatory for new types of ALKS equipped vehicles from September 1, 2023, and will become mandatory for all ALKS equipped vehicles from September 1, 2027.