UN R79 Base text (04 series) · UNECE Regulation No. 79 (ECE R79) — Uniform provisions concerning the approval of vehicles with regard to steering equipment.
UN R79 — 04 series of amendments
Changes from 03 series of amendments (supplement 5)
- What changed
- New paragraph 5.1.6.3. sets requirements for a Risk Mitigation Function (RMF), an emergency function for the event that the driver becomes unresponsive.
- The RMF may change lanes only if the vehicle is equipped with detection capabilities to the front, side and rear.
- From 1 September 2025, Contracting Parties are not obliged to accept approvals to the preceding series. They must continue to accept them for vehicles not affected by paragraph 5.1.6.3.9.
- Why
- Functions with lane change that cope with temporary driver inability to control the vehicle were not considered in UN Regulation No. 79.
- The amendment seeks to permit such a function, which aims to reduce risks in traffic and could so far not be type-approved.
- The expert from OICA recalled that safety systems type-approved in the past could no longer receive a type approval under the 03 series of amendments.
Q1What changed109 changes
Definitions of RMF, target stop area, beside the road and Lane Change Procedure (paras. 2.3.4.5., 2.4.16., 2.4.19. and 2.4.20.)
New paragraph 2.3.4.5. defines the Risk Mitigation Function (RMF) as an emergency function for the event that the driver becomes unresponsive. It can automatically steer the vehicle for a limited duration to bring it to a safe stop within a target stop area. A “target stop area” is a potential stopping area, for example the emergency lane, hard shoulder or own lane of travel. “Beside the road” means the area of road surface beyond the carriageway boundaries that is not a hard shoulder or refuge area. Paragraph 2.4.16. no longer says “in the case of ACSF of Category C” in the definition of a “Lane Change Procedure”. The definition and its operation (a) no longer say that the direction indicator lamps are activated “by a deliberate action of the driver”.
Start of an RMF intervention, manual activation and M2/M3 vehicles (paras. 5.1.6.3., 5.1.6.3.1. and 5.1.6.3.11.)
Vehicles equipped with an RMF must fulfil the requirements of new paragraph 5.1.6.3., and an RMF system is subject to the requirements of Annex 6. An RMF must start an intervention only if the driver is directly or indirectly assessed to be unresponsive, or if it is manually activated. A means for manual activation, if provided, must be protected against unintentional operation and accessible to the driver and to passengers adjacent to the driver. In M2/M3 vehicles, a passenger who manually activates the RMF must get an indication until the intervention starts or the driver overrides the activation. The driver must be able to override the passenger's request to suppress the RMF intervention. In a vehicle of Class I, II or A, the RMF must give the passengers an acoustic and optical indication before the intervention would start.
Driver warnings, hazard warning lights and failures (paras. 5.1.6.3.2., 5.1.6.3.4. and 5.1.6.3.8.)
Unless a request for action was already given or the system was manually activated, optical and acoustic and/or haptic warnings must precede each intervention. This warning phase must start at least 5 seconds before the RMF starts an intervention. This does not apply if vehicle control is required sooner to prevent crossing the lane markings or to keep an appropriate distance to other vehicles. Every RMF intervention must be indicated to the driver by an optical and additionally an acoustic and/or haptic warning signal as long as it exists. The signal to activate the hazard warning lights must be generated with the start of the intervention. If the RMF system detects any failures that prevent an intervention, this must be signalled to the driver.
Assistance systems, override, deceleration and standstill (paras. 5.1.6.3.3., 5.1.6.3.5. to 5.1.6.3.7. and 5.1.6.3.10.)
An RMF intervention must not unreasonably deactivate or suppress the functionality of activated assistance systems, for example AEBS. The driver must be able to override the RMF intervention at any time by a distinct action. The RMF must implement strategies that protect against unintentional override by inputs to the driving controls. The deceleration demand during the intervention must not be greater than 4 m/s², unless required by the surrounding traffic or for very short durations. Once the RMF has brought the vehicle to a safe stop in the target stop area, the vehicle must not move away without manual input. If the driver remains unresponsive once the RMF has brought the vehicle to standstill, the system must implement strategies to draw external attention.
Lane changes during an RMF intervention (para. 5.1.6.3.9.)
The RMF may change lanes only if the vehicle is equipped with detection capabilities to the front, side and rear. A lane change procedure must not start within the first 5 s following the start of the RMF intervention. Lane changes during the intervention must not be performed towards a lane intended for traffic moving in the opposite direction. During a lane change manoeuvre, the RMF must aim to avoid more than 1 m/s² lateral acceleration beyond that from the lane curvature. It must also aim to avoid inducing a longitudinal deceleration of more than 3.7 m/s² for a vehicle approaching from the rear. When bringing the vehicle to a stop beside the road, the vehicle speed must not exceed 10 km/h.
System information data and tests for RMF (para. 5.1.6.3.12. and Annex 8, para. 3.6.)
The system information data must be provided to the Technical Service at the time of type approval, together with the Annex 6 documentation package. The data include how the system confirms that the driver is unresponsive and whether it can perform lane changes. Annex 8, paragraph 3.6., adds RMF tests for a safe stop inside and for a safe stop outside its own lane of travel. In Scenario A a lane change manoeuvre is possible; in Scenario B another vehicle in the target lane prevents it. Specific details of the mandatory tests must be discussed and agreed between the vehicle manufacturer and the Technical Service.
Transitional provisions for the 04 series and general transitional provisions (paras. 12.3. and 12.4.)
The general transitional provisions, former paragraphs 12.3. and 12.3.1., are renumbered as paragraphs 12.4. and 12.4.1. From 1 September 2023, Contracting Parties are not obliged to accept UN type approvals to the preceding series, first issued after 1 September 2023. Until 1 September 2025, they must continue to accept such approvals first issued before 1 September 2023. From 1 September 2025, they are not obliged to accept type approvals issued to the preceding series. Notwithstanding paragraphs 12.3.2. and 12.3.4., they must continue to accept approvals to a preceding series for vehicles not affected by paragraph 5.1.6.3.9. Paragraph 12.4.1. now says “extensions thereof” instead of “extension thereof”.
Q2Why it changed
- Proposed by
- Experts from the International Organization of Motor Vehicle Manufacturers and the European Association of Automotive Suppliers
- Working party
- GRVA, 10th session (May 2021)
Reasons
UN Regulation No. 79 did not consider functions with lane change that cope with temporary driver inability to control the vehicle. For example, the inability can be caused by a health problem.
Source
“Functions with lane change, to cope with temporary driver inability, to control the vehicle (e.g. caused by a health problem) are currently not considered in UN Regulation No. 79.”
The proposed RMF would warn and possibly call back the driver while it automatically performs emergency lane changes. Its aim is to bring the vehicle, if possible (depending on traffic), to a standstill in an area with a low risk of collision. The proposal calls this area the “target stop area”, for example the hard shoulder. It says that this is the safest area to stop, because emergency vehicles have access and the collision risk at the emergency lane is low.
Sources (2)
“would warn and possibly call back the driver while automatically performing emergency lane change(s), with the aim to bring the vehicle, if possible (depending on traffic, etc.), to a standstill in an area with a low risk of collision”
“called “target stop area” in the proposal, e.g. hard shoulder), because it is the safest area to stop (access of emergency vehicles, low collision risk at the emergency lane”
The amendment seeks to permit such a function, which aims to reduce risks in traffic and could so far not be type-approved. An RMF could avoid or mitigate uncontrolled vehicle movement.
Sources (2)
“The amendment seeks to permit such a function, aimed at reducing risks in traffic, which could so far not be type-approved.”
“Uncontrolled vehicle movement could be avoided or mitigated by an RMF.”
The expert from OICA recalled that provisions for Risk Mitigation Functions would need to be adopted. The reason he gave was that safety systems type-approved in the past could no longer receive a type approval under the 03 series of amendments. GRVA concluded that removing such systems from the market was an issue.
Sources (3)
“The expert from OICA introduced ECE/TRANS/WP.29/GRVA/2021/13.”
“Risk Mitigation Functions related provisions would need to be adopted because safety systems that were type-approved in the past could no longer being able to receive a type approval under the 03 series of amendments”
“GRVA concluded that removing such systems from the market was an issue.”
An earlier proposal suggested RMF as an additional subcategory of an Emergency Steering Function. As GRVA advised at its fourth session, the proposal introduces the provisions for a potential lane change during the intervention as a separate new function.
Sources (2)
“ECE/TRANS/WP.29/GRVA/2020/16 suggested the introduction of RMF as an additional subcategory of an Emergency Steering Function.”
“As advised by GRVA in its fourth session, this proposal introduces the provisions for a potential lane change during the intervention as a separate new function”
Document trail
- 2019-11ProposalECE/TRANS/WP.29/GRVA/2020/16Earlier proposal by OICA and CLEPA, as a subcategory of an Emergency Steering Function
- —RevisedGRVA-07-22Proposal for a new 04 series by OICA and CLEPA, for the 7th GRVA session
- 2020-11RevisedECE/TRANS/WP.29/GRVA/2021/13Proposal for a new 04 series of amendments, based on GRVA-07-22
- —Amended in sessionGRVA-09-43Changes to ECE/TRANS/WP.29/GRVA/2021/13, introduced by the expert from OICA at the 9th GRVA session
- —Working party adoptsECE/TRANS/WP.29/GRVA/9Session report, para. 83: GRVA agreed to forward GRVA-09-43, subject to reconfirmation
- 2021-04Sent to WP.29ECE/TRANS/WP.29/2021/82Text sent to WP.29 and AC.1, subject to reconfirmation by GRVA
- —Amended in sessionGRVA-10-38Changes to ECE/TRANS/WP.29/2021/82 at the 10th GRVA session
- —Working party adoptsECE/TRANS/WP.29/GRVA/10Session report, para. 60
- —Amended in sessionWP.29-184-05Amendments submitted by the Chair of GRVA, reproduced in Annex VI of ECE/TRANS/WP.29/1159
- 2021-06WP.29 adoptsECE/TRANS/WP.29/1159Adopted at the 184th session (session report, para. 127)
- 2022-01-07In forceC.N.11.2022.TREATIES-XI.B.16.79UN depositary notification
Q3Who is affected
Vehicle manufacturer
- For vehicles equipped with an RMF, make sure that it starts an intervention only in the cases of paragraph 5.1.6.3.1.
- Test the RMF warning signals before and during an intervention against paragraph 5.1.6.3.2.
- If the RMF can change lanes, declare the detection ranges to the front, side and rear.
- Be ready to show that the requirements of paragraph 5.1.6.3. are fulfilled in the whole operating range of the RMF.
- Agree the specific details of the mandatory RMF tests with the Technical Service.
- Check whether your vehicles with approvals to a preceding series are affected by paragraph 5.1.6.3.9.
Component supplier
- Make sure that your RMF software starts an intervention only in the cases of paragraph 5.1.6.3.1.
- Make sure that the deceleration demand during an RMF intervention meets paragraph 5.1.6.3.6.
- Make sure that RMF lane changes aim to stay within paragraphs 5.1.6.3.9.8.1. and 5.1.6.3.9.8.2.1.
- Give the vehicle manufacturer the information it needs for the system information data of paragraph 5.1.6.3.12.
Technical service / Approval authority
- Assess whether the declared detection ranges correspond to the lane change strategy of the RMF.
- During the relevant test in Annex 8, check that the vehicle's sensing system detects vehicles.
- Agree the specific details of the mandatory RMF tests with the vehicle manufacturer.
- Be ready for the demonstration of the strategies against unintentional override at type approval.
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ⓘ This report gives advice only. It is not legal or type-approval advice.
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