GB/T 6323-2014Controllability and Stability Test Procedure for Automobile (English PDF)

3.3 The measurement range and maximum error of the various measuring instruments

shall satisfy the requirements in Table 1.

3.5 The various sensors are installed in accordance with their respective instruction manuals. Specifically speaking, the speedometer shall be installed on the longitudinal symmetry plane of the vehicle; the controllability and stability tester shall be as close to the center of mass of the vehicle as possible.

4.1 Test Vehicles

4.1.1 Before the test, determine the wheel positioning parameters. Check, adjust and

tighten the steering system and suspension system; lubricate them as required.

4.1.2 If new tires are used for the test, before the test, they shall at least go through

200 km of normal running. If used tires are used for the test, after the test is completed, the residual tire crown pattern depth shall be not less than 1.6 mm. The tire pressure shall comply with the exit-factory technical requirements of the vehicle.

4.1.4 In pylon course slalom test, the load state is the maximum design total mass of the vehicle. In steering transient response test (steering wheel angle step input and steering wheel angle pulse input),

4.2 Test Site and Environment

4.2.1 Test site shall be dry, flat and clean, with cement concrete or asphalt pavement.

The slope in any direction shall not be greater than 2%. In terms of the controllability and stability test of the central area of steering wheel, the slope shall be not greater than 1%.

4.2.2 The wind speed shall be not greater than 5 m/s.

5.1 Test Instruments

5.2 Measurement Parameters

5.3 Test Methods

5.3.1 On the test site, in accordance with the stipulations of Figure 1 and Table 2, set up 10 stakes.

5.4 Data Processing of Pylon Course Slalom Test

5.4.1 Test speed

The test speed for the ith pylon course slalom test shall be determined in accordance with Formula (1).

5.4.3 Average yaw velocity

The average yaw velocity of the ith test shall be determined in accordance with Formula (3).

5.4.4 Average roll angle of vehicle body

The average roll angle of vehicle body of the ith test shall be determined in accordance with Formula (4).

5.5 Result Expression of Pylon Course Slalom Test

5.5.1 Fill in the peak data of the time-history curve of the various measurement variables within the effective staking area and the driver’s subjective evaluation into

Table 3.

5.5.2 In the form of Figure 3, fit-draw the relational graph of the average yaw velocity and the vehicle speed.

5.5.3 In the form of Figure 4, fit-draw the relational graph of the average steering wheel angle and the vehicle speed.

5.5.4 In the form of Figure 5, fit-draw the relational graph of the average roll angle of vehicle body and the vehicle speed.

6.1 Test Instruments

6.3 Test Methods

6.3.1 The test speed is determined in accordance with 70% of the maximum speed of the tested vehicle (rounded off to an integer multiple of 10). However, the maximum test speed should not exceed 120 km/h.

6.3.2 Before the test, at the test speed, run for 10 km, so as to warm up the tires.

6.4 Test Data Processing

6.4.1 The steady-state values of the various measurement variables shall adopt the mean value after entering the steady state. If the rate of change of the vehicle’s forward speed is greater than 5%, or if the change of the steering wheel angle exceeds 10% of the mean value, then, this test is invalid.

6.4.2 Adopt the method specified in 5.4.5.1 a) or 5.4.5.1 b) to obtain the time-history of lateral acceleration; determine the steady-state acceleration value.

6.4.3 In accordance with Figure 7, determine the response time of the yaw velocity and the lateral acceleration.

6.4.4 In accordance with Figure 7, determine the response time of the yaw velocity. If peak value does not emerge, it shall be explained in the remarks in Appendix A.

6.4.5 The overshoot of yaw velocity shall be determined in accordance with Formula (7).

6.5.2 In accordance with the following curve forms, express the test data at different lateral accelerations.

7.1 Test Instruments

7.2 Measurement Parameters

7.3 Test Methods

7.3.1 The test speed shall be 70% of the maximum design speed of the tested vehicle and rounded off to an integer multiple of 10.

7.3.5 During the test, in accordance with the triangular pulse curve shown in Figure 16, turn the steering wheel (steering wheel angle pulse input) at least three times respectively in the left direction and the right direction. The time interval between each input shall be not less than 5 s.

7.4 Test Data Processing

7.5 Test Result Expression

7.5.1 In accordance with the mean value of the test data processing result, turn the steering wheel to the left and the right, respectively draw the amplitude-frequency phase-frequency characteristic diagram of the vehicle, as it is shown in Figure 17 (in

Figure 17, the X-coordinate is a logarithmic coordinate, or, linear coordinate may also be used. The X-coordinate shall be 0 Hz ~ 3 Hz).

8.1 Test Instruments

8.3 Test Methods

8.3.1 Low-speed returnability test

8.3.1.1 On the test site, use bold colors to draw a circle with a radius of not less than

15 m.

8.3.2.2 The test vehicle speed shall be 70% of the maximum speed of the tested vehicle and rounded off to an integer multiple of 10.

8.3.2.3 Turn on the instrument power to let it reach the normal working temperature.

8.4 Returnability Test Data Processing

The time-history curve of yaw velocity is divided into two types. convergent type (shown in Curve 1~4 in Figure 18) and divergent type (shown in Curve 5 ~ 6 in Figure 18). In terms of the divergent type, no data processing is performed. In terms of the convergent type, in accordance with the left-turning and right-turning, respectively determine the following indexes.

9.1 Test Instruments

9.3 Test Methods

9.3.1 On the test site, use bold colors to draw a lemniscate trajectory (see Figure 24).

The polar coordinate equation of the lemniscate trajectory shall be determined in accordance with Formula (22). The definitions of symbols in the formula are shown in

Figure 24.

9.4 Test Data Processing

9.4.1 In accordance with the recorded steering wheel angle and the applied torque, in accordance the lemniscate path of every week, organize into the Msw-deltasw curve shown in Figure 25, or directly adopt the above-mentioned parameters obtained through

9.4.4 Work function of steering wheel

9.4.4.1 The work function of every week of running along the lemniscate path shall be determined in accordance with Formula (27).

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