Document ID: chunk:federal_register_of_legislation:F2021C00477:body:0:p76
Version: federal_register_of_legislation:F2021C00477
Segment Type: other
Provision Reference: 
Character Range: 198389–201064

manufacturer in accordance with paragraph 22.1.2. or 22.1.3 of Annex 1.
 After t = t0 + 0.8 s and until the vehicle has slowed down to a speed of 15 km/h, the brake pedal force shall be maintained in a corridor between FABS, upper and FABS, lower, where FABS, upper is 0.7 FABS and FABS, lower is 0.5 FABS.
 The requirements are also considered to be met if, after t = t0 + 0.8 s, the pedal force falls below FABS, lower provided the requirement of paragraph 4.3. is fulfilled.
4.3. Data evaluation
 The presence of BAS 'B' is demonstrated if a mean deceleration (aBAS) of at least 0.85 ∙ aABS is maintained from the time when t = t0 + 0.8 s to the time when the vehicle speed has been reduced to 15 km/h.

       Figure 2
       Example of test 2 of a category "B" BAS system

Annex 9

Appendix 1

Use of the dynamic stability simulation
 The effectiveness of the electronic stability control system may be determined by computer simulation.
1. Use of the simulation
1.1. The vehicle stability function shall be demonstrated by the vehicle manufacturer to the Type Approval Authority or Technical Service by simulating the dynamic manoeuvres of paragraph 5.9. of Annex 9.
1.2. The simulation shall be a means whereby the vehicle stability performance shall be demonstrated with:
(a) The yaw rate, one second after completion of the Sine with Dwell steering input (time T0 + 1);
(b) The yaw rate, 1.75 seconds after completion of the Sine with Dwell steering input;
(c) The lateral displacement of the vehicle centre of gravity with respect to its initial straight path.
1.3. The simulation shall be carried out with a validated modelling and simulation tool and using the dynamic manoeuvres of paragraph 5.9. of Annex 9 under the test conditions of paragraph 4. of Annex 9.
 The method by which the simulation tool is validated is given in Appendix 2 to this annex.

Annex 9

Appendix 2

Dynamic stability simulation tool and its validation
1. Specification of the simulation tool
1.1. The simulation method shall take into account the main factors which influence the directional and roll motion of the vehicle. A typical model may include the following vehicle parameters in an explicit or implicit form:
(a) Axle/wheel;
(b) Suspension;
(c) Tyre;
(d) Chassis/vehicle body;
(e) Power train/driveline, if applicable;
(f) Brake system;
(g) Pay load.
1.2. The Vehicle Stability Function shall be added to the simulation model by means of:
(a) A subsystem (software model) of the simulation tool; or
(b) The electronic control box in a hardware-in-the-loop configuration.
2. Validation of the simulation tool
2.1. The validity of the applied modelling and simulation tool