Document ID: chunk:federal_register_of_legislation:F2018C00341:body:0:p38
Version: federal_register_of_legislation:F2018C00341
Segment Type: other
Provision Reference: 
Character Range: 110025–112745

quantity "A" is determined.  "A" is the steering wheel angle in degrees that produces a steady state lateral acceleration (corrected using the methods specified in paragraph 5.11.3.) of 0.3g for the test vehicle.  Utilizing linear regression, A is calculated, to the nearest 0.1 degrees, from each of the six slowly increasing steer tests.  The absolute value of the six A values calculated is averaged and rounded to the nearest 0.1 degrees to produce the final quantity, A, used below.

       5.7. After the quantity A has been determined, without replacing the tyres, the tyre conditioning procedure described in paragraph 5.5. is performed again immediately prior to conducting the Sine with Dwell test of paragraph 5.9.  Initiation of the first Sine with Dwell test series shall begin within two hours after completion of the slowly increasing steer tests of paragraph 5.6.

       5.8. Check that the ESC system is enabled by ensuring that the ESC malfunction and "ESC Off" (if provided) tell-tales are not illuminated.

       5.9. Sine with Dwell test of oversteer intervention and responsiveness

        The vehicle is subjected to two series of test runs using a steering pattern of a sine wave at 0.7 Hz frequency with a 500 ms delay beginning at the second peak amplitude as shown in Figure 2 (the Sine with Dwell tests).  One series uses anticlockwise steering for the first half cycle, and the other series uses clockwise steering for the first half cycle.  The vehicle is allowed to cool-down between each test runs for a period of 1.5 to 5 minutes, with the vehicle stationary.

       5.9.1. The steering motion is initiated with the vehicle coasting in high gear at 80 ± 2 km/h.

       5.9.2. The steering amplitude for the initial run of each series is 1.5 A, where A is the steering wheel angle determined in paragraph 5.6.1.

       5.9.3. In each series of test runs, the steering amplitude is increased from run to run, by 0.5 A, provided that no such run will result in a steering amplitude greater than that of the final run specified in paragraph 5.9.4.

       5.9.4. The steering amplitude of the final run in each series is the greater of 6.5 A or 270 degrees, provided the calculated magnitude of 6.5 A is less than or equal to 300 degrees.  If any 0.5 A increment, up to 6.5 A, is greater than 300 degrees, the steering amplitude of the final run shall be 300 degrees.

       5.9.5. Upon completion of the two series of test runs, post processing of yaw rate and lateral acceleration data is done as specified in paragraph 5.11.

       5.10. ESC malfunction detection

       5.10.1. Simulate one or more ESC malfunction(s) by disconnecting the power source to any ESC component, or