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GRRF, former subsidiary body to WP.29

The Working Party on Braking and Running Gear (GRRF) was the subsidiary body of the World Forum for Harmonization of Vehicle Regulations (WP.29) that prepares regulatory proposals on vehicle automation, ADAS, active safety, braking and running matters to WP.29. This group of experts conducts research and analysis to develop and propose active safety requirements of vehicles.

  • At its February 2018 session, the Inland Transport Committee (ITC) acknowledged the importance of WP.29 activities related to automated, autonomous and connected vehicles and requested WP.29 to consider establishing a dedicated subsidiary Working Party (Groupe de Rapporteurs - GR).
  • Following this request, WP.29, at its June 2018 session, decided to convert the Working Party on Brakes and Running Gear (GRRF) into a new Working Party "Groupe de Rapporteurs pour les Véhicules Autonomes" (GRVA).
Latest news from GRRF

June 2018:

  • Following the Inland Transport Committee (ITS) request (ECE/TRANS/274, para 52), WP.29 decided (ECE/TRANS/WP.29/1139, para. 33) to convert the Working Party on Brake and Running Gear (GRRF) in the Working Party on Automated/Autonomous and Connected Vehicles (GRVA), to be endorsed by ITC at its February 2019 session.

March 2018:

  • Adoption of the 2nd ACSF package with provisions for ACSF of Category C (Automated lance change manoeuvring initiated by the driver)
  • Discussion of the WP.29 restructuring in order to create a dedicated group dealing with vehicle automation

February 2018 - Last meeting of GRRF:

  • Ressources management of the activities related to Automatically Commanded Steering Functions (ACSF).
  • 1st presentation of Remonte Control Manoeuvring (RCM) draft provisions
  • Discussion of provisions for the automatic activation of AEBS systems
  • Development of a draft UN Regulation dealing with agricultural couplings

December 2017:

  • Completion of the drafting of provisions for the type approval of:
    • ACSF of Category C (Automated Lane Change initiated by the driver)
    • Emergency Steering Functions (ESF)
  • Updates to Annex 6 (CEL) 

November 2017:

  • Endorsement of the revised ToR of the IWGs on ACSF and AEBS
  • Presentations by OICA and Catapult (UK) on "horizontal regulation" for HAD
  • Decision to establish an IWG on AD
  • Discussion on a restructuration of WP.29 and its GRs

September 2017:

  • Discussion on automatic reactivation of AEBS
  • Adoption of the revised ToR of the IWG on ACSF - discussion of WP.29-172-08
  • Combined session WP.1 - WP.29/GRRF (secondary tasks, cyber security)

June 2017:

  • Adoption by WP.29/AC.1 adopted all amendment proposals proposed by GRRF
  • WP.29 referred WP.29-172-08 to GRRF and asked GRRF to develop its roadmap to address SAE Level 3 and 4 technologies
  • Brainstoming about the inclusion of automated vehicles into the UNECE/WP.29 regulatory framework
  • Announcement of a TF on the testing of AD

March 2017:

  • Agreement to brainstorm on a specific vehicle category for autonomous vehicles (incl pods etc.) at the June 2017 session
  • Adoption of the first ACSF package (incl. RCP, Lane keeping "hands on")
  • Endorsement of the (re)establishment of the IWG on AEBS - M1&N1
  • First report from the TF on Cyber Security /OTA - Adoption of guidelines for CS and Data protection
  • Decision to regulate SAE Levels 3 and 4

January 2017:

  • Establishment of the IWG on AEBS to regulate AEB for light vehicles
  • Adoption of provisions for the coupling of modular vehicle combinations (incl. dollies)

November 2016:

  • Adoption by WP.29 (AC.1/AC.3) of the proposed 04 series of amendments to Regulation No. 78 and Amend. 1 to GTR No. 16
  • Decision to establish a Task Force on Cyber Security and Over-The-Air updates

September 2016:

  • Ad hoc session of the ITS/AD informal group.
  • Combined meeting of experts of WP.1 and GRRF.
  • Adoption of an amendment to UN R79 (CSF and ACSF A and B1).
  • Request to develop amendments to GTRs Nos. 3 and 16 reviewed.

June 2016:

  • WP.29 resume consideration of the discussion on the performance of automotive systems in conditions other than those tested.
  • WP.29 agreed with the establishment of an informal working group dealing with mechanical coupling for agricultural vehicles.
  • WP.29 discussed cyber security and data protection guidelines based on the status report provided by the IWG on ITS/AD.
  • WP.29/AC.1 adopted a number of amendments to UN Regulations in the remit of GRRF as well as four new UN Regulations (related to the IWVTA activities)
  • At the request of a CP, all proposals to be reviewed by AC.3 were deferred to the November 2016 session.

March 2016:

  • WP.29 discussed the performance of automotive systems in conditions other than those tested according to the regulated test procedures and the potential inherent risks that some systems, especially those relying on software could be designed to work only in the limited conditions corresponding to those tested rather than in all the relevant driving conditions. WP.29 launched a case study.
  • WP.29 discussed Cyber Security and Privacy risks during its ITS/AD session.
  • WP.29/AC.1 adopted Supplements to UN Regulations Nos. 55, 130 and 131.

February 2016:

  • GRRF received information about (1) the EU high level automotive group GEAR 2030, (2) the C-ITS activities within the EU and (3) the work in Japan on the "Deadman system" guideline.
  • GRRF adopted several amendments to Tyre Regulations, incl. the draft Amend.1 to GTR No. 16 and TPMS
  • GRRF adopted several amendments to Regulation No. 78 on Motorcycle braking (ABS scope extension to cover tricycles, ESS, conditions for the installation of an ABS switch)
  • GRRF agreed to review Regulation No. 90.
  • Within the IWVTA activities, GRRF splitted braking (R13-H), BAS, ESC, R64 and TPMS as independent regulations.

November 2015:

  • WP.29 received brief report on the work done at the UNECE level of vehicle automation. 
  • WP.29 elected the Representative of Finland as its Ambassador between the IWG on ITS/AD and the WP.1 IWG on AD

September 2015:

  • GRRF received a presentation and a demo of a vehicle equipped with the Remote Control Parking feature. GRRF agreed to report about issues related to cybersecurity to WP.29.
  • GRRF adopted several proposals amending existing Tyre regulations and an update of UN Regulation No. 55.
  • GRRF adopted amendments to UN Regulation No. 90 introducing provisions for the approval of replacement brake disks for L-category vehicles.
  • GRRF introduced EMC requirements in Regulation No. 78 (Motorcycle braking)

February 2015:

  • GRRF drafted an amendment to Regulation No. 109 (Retreaded tyres for commercial vehicles and their trailers) setting provisions regarding retreaded tyres for use in severe snow conditions.
  • GRRF reviewed the guidance provided by the IWG on ITS/AD answering to the GRRF request for guidance to WP.29 in November 2014 on advances innovations and self-driving technologies.
  • GRRF endorsed the proposal to establish an IWG on Automated Commanded Steering Functions (ACSF).
  • The expert from Japan, Vice Chair of GRRF, presented the regulatory development in his country on the mandatory fitting of advanced safety systems

November 2014:

  • WP.29/AC.3 adopted the Tyre GTR. 
  • GRRF requested guidance on the way it should work on advances innovations and self-driving technologies.

September 2014:

  • GRRF received a presentation by the automotive supplier industry about future innovations such as "valet parking" and "highway autopilot" (see here)
  • GRRF reviewed specific proposals for amendments to existing regulations that would allow the approval of self-steering systems e.g. on highways and decided to request guidance from policymakers.

June 2014:

WP.29, during its March 2014 session requested the UNECE secretariat to organize an Extraordinary Session of GRRF on 26 June 2014 in order: 
- to work on the draft Tyre GTR,  
- to efficiently incorporate the ongoing research results by the United States of America into the draft UN GTR on tyres.

March 2014:

UNECE's World Forum for Harmonization of Vehicle Regulation (WP.29) adopted technical provisions developed by GRRF within the last years concerning Automated Coupling Vehicles (ACV). Experts reported that each year, some drivers/operators are having accidents when manually coupling or de-coupling trailers or semi-trailers from the truck. GRRF defined safety provisions that would allow the deployment of automated coupling devices for trucks and their trailers, increasing safety and ensuring interoperability of towing equipment. 

February 2014:

GRRF received a presentation about Vehicle Platooning. More here: 76th session of GRRF

September 2013:

GRRF finalized the work on the definition of a test procedure for discriminating snow tyres for use in severe snow conditions for comercial vehicle tyres.

February 2013:

GRRF finalized the work on new amendments for the AEBS Regulation implementing crash avoidance provisions and the corresponding homologation test.

November 2012:

UNECE's World Forum for Harmonization of Vehicle Regulation (WP.29) adopted 2 new regulations that will enter into force in mid-2013 (i.e. 6 months after adoption) which were developed by GRRF within the last years:

Lane Departure Warning System (LDWS)

This system, fitted to trucks and coaches, is warning the driver, through an optical, acoustic or haptic warning, of an unintentional departure of his vehicle out of the travel lane. It thus aims at minimizing accidents by addressing three main causes of collisions: driver errors, distractions and drowsiness.

Advanced Emergency Braking System (AEBS)

The system, fitted to trucks and coaches, is using sensors to monitor the proximity of an object or a vehicle in front and detect situations where the relative speed and distance between the two vehicles suggests a collision will take place. The system provides the driver with a warning and activates the vehicle braking system to decelerate the vehicle with the purpose of avoiding or mitigating the severity of a collision in the event that the driver does not respond to the warning.
Here a video made at the occasion of a demonstration organized in Geneva in May 2011 prior to a special session of GRRF, introducing the system to the GRRF experts.

How it works

Until June 2018, GRRF convened officially twice a year and entrusted informal working groups with specific problems that needed to be solved urgently or that require special expertise.  In 2017 and 2018, around 120 experts regularly participated to the GRRF sessions to address various issues related to Active Safety, Vehicle Automation, ADAS, Tyres, Coupling Devices, Braking, Steering etc.


This Working Party was open to the governmental experts from any member Country of the United Nations, to any regional economic integration organization set up by member countries of the United Nations, and to experts of governmental organizations. Experts of non-governmental organizations (NGOs) participated in a consultative capacity.  Final decisions on recommendations to WP.29 were taken by the government representatives.

The work of the GRRF experts was transparent: all agendas, working documents and reports are available on this internet website.

 Two sessions per year

Demonstration activities