Report of the ad‐hoc working group organized in accordance with the recommendation of the 58th GRB session to consider testing and evaluation of the variant method using the dω/dt form proposed by Russia.

Proposal to elaborate on the concept of tyre deceleration (dω/dt) in the test procedures. The Russian Federation has developed a “Deceleration Calculator” for use in the UN R117 procedures. Following work by an ad hoc group (including NAMI, UTAC, and ETRTO) formed to review and validate this tool, Russia has prepared this new proposal, modifying the version (document GRB/2013/10) submitted at the last GRB session. The changes primarily concern the explanation of the tool rather than the basic mathematical equations.

Report of the ad‐hoc working group organized in accordance with the recommendation of the 58th GRB session to consider testing and evaluation of the variant method using the dω/dt form proposed by Russia.

Full report of the ad hoc group on the development of the method for determining tire rolling resistance using the variant dω/dt method.

Pursuant to the introduction of the deceleration method for measuring tire rolling resistance using the dω/dt approach (“Deceleration Calculator”) proposed by NAMI and accepted by GRB, UTAC (France) provides information on the results of tests conducted to confirm repeatability and reproducibility of the new method using different machines.