Rough road drive simulation and evaluation for vehicle control system

• US 20050268708A1
• Filed: 05/26/2005
• Published: 12/08/2005
• Est. Priority Date: 05/27/2004
• Status: Active Grant

• Current Assignee: Nissan Motor Co., Ltd.
• Original Assignee: Nissan Motor Co., Ltd.
• Inventors: Nakagawa, Syuuichi, Murakami, Hiroshi, Saitou, Haruki, Satou, Osamu
• Granted Patent: US 7,278,316 B2
• Time in Patent Office: Days
• US Class Current: 73/146
• CPC Class Codes: B60T 2210/14 Rough roads, bad roads, gravel roads
• CPC Class Codes: B60T 8/172 Determining control parameters used in the regulation, e.g. by calculations involving measured or detected parameters B60T8/17551 takes precedence

Abstract

A rough road drive simulation apparatus for testing a vehicle motion control system includes a real-time simulator. The real time simulator simulates a rough road driving state by entering, to a vehicle model representing a vehicle equipped with the vehicle motion control system, a wheel disturbance input based on a correlation between a road surface disturbance and a wheel rotation variation.

Claims

1. A rough road drive simulation apparatus for testing a vehicle motion control system, the simulation apparatus comprising:

a real-time simulator configured to simulate a rough road driving state by entering, to a vehicle model representing a vehicle equipped with the vehicle motion control system, a wheel disturbance input based on a correlation between a road surface disturbance and a wheel rotation variation.

2. The rough road drive simulation apparatus as claimed in claim 1, wherein the wheel disturbance input is in the form of a noise superimposed on a wheel speed signal inputted to the vehicle model.

3. The rough road drive simulation apparatus as claimed in claim 2, wherein the wheel disturbance input is inputted to the vehicle model in a plurality of disturbance input patterns different in continuity of a waveform of the noise, the disturbance input patterns including a single input pattern and a continuous input pattern.

4. The rough road drive simulation apparatus as claimed in claim 2, wherein the noise is determined by using, as parameter, a wheel speed variation width and a wheel speed variation rate.

5. The rough road drive simulation apparatus as claimed in claim 4, wherein the wheel disturbance input is inputted to the vehicle model in a plurality of different forms representing different road surface irregular conditions by using an input data map set by the wheel speed variation width along one of vertical and horizontal axes, and the wheel speed variation rate along the other of the vertical and horizontal axes.

6. The rough road drive simulation apparatus as claimed in claim 1, wherein the rough road drive simulation apparatus further comprises an estimator to estimate a system actuation sensitivity of the vehicle motion control system by comparing real-time simulation data obtained by simulation of the real-time simulator, with reference simulation data.

7. The rough road drive simulation apparatus as claimed in claim 6, wherein the real-time simulator is configured to perform simulation in each of disturbance patterns representing different rough road patterns;

and the estimator is configured to accumulate the real-time simulation data in the form of a real-time simulator data map by entering data on actuation or non-actuation of the vehicle motion control system in the real-time simulation data map; and

to estimate the system actuation sensitivity by comparing the real-time simulation data map with the reference simulation data in the form of a reference data map.

8. The rough road drive simulation apparatus as claimed in claim 7, wherein the real-time simulator is configured to perform simulation in each of the disturbance patterns at each of vehicle speed levels.

9. The rough road drive simulation apparatus as claimed in claim 7, wherein the estimator is configured to check consistency between a system actuation range of the real-time simulation data map and a system actuation range of the reference data map, and to adjust the actuation sensitivity of the vehicle motion control system so as to increase the consistency.

10. A rough road drive simulation apparatus for testing a vehicle motion control system, the simulation apparatus comprising:

a virtual test driving section adapted to be connected with the vehicle motion control system and configured to test a response of the vehicle motion control system in a simulated driving environment of a virtual vehicle model, by inputting a wheel speed signal to the vehicle control system in the virtual vehicle model, the virtual test driving section being further configured;

to simulate a driving state of the virtual vehicle model on a rough road by inputting, to the vehicle motion control system, a noise-superimposed wheel speed signal obtained by superimposing a road disturbance noise to the wheel speed signal;

to examine the response of the vehicle motion control system to the noise-superimposed wheel speed signal; and

to adjust a sensitivity parameter of the vehicle motion control system so as to adjust a sensitivity of the vehicle motion control system toward a desired reference.

11. The rough road simulation apparatus as claimed in claim 10, wherein the virtual test driving section is configured to produce the road disturbance noise signal in a plurality of different waveforms determined by a first road noise parameter representing an amplitude of the road surface disturbance and a second road noise parameter representing a frequency of the road surface disturbance;

and to simulate the driving state of the virtual vehicle model by using each of the waveforms of the road disturbance noise signal.

12. The rough road simulation apparatus as claimed in claim 10, wherein the virtual test driving section is configured to simulate the driving state of the virtual vehicle model on a rough road, by inputting, to the vehicle motion control system, a first noise-superimposed wheel speed signal obtained by superimposing a first road disturbance noise to a first wheel speed signal representing a wheel speed of a first wheel of the virtual vehicle, and a second noise-superimposed wheel speed signal obtained by superimposing a second road disturbance noise to a second wheel speed signal representing a wheel speed of a second wheel of the virtual vehicle.

13. A rough road drive simulation process for testing a vehicle motion control system, the simulation process comprising:

setting the vehicle motion control system in a simulated virtual environment including a virtual vehicle model;

inputting a noise-superimposed wheel speed signal produced by superimposing a road disturbance noise signal to a wheel speed signal, to the vehicle motion control system in the simulated virtual environment;

examining a response of the vehicle motion control system to the noise-supposed wheel speed signal; and

adjusting a control parameter of the vehicle motion control system so as to adjust the response of the vehicle motion control system to a desired reference.

14. The rough road drive simulation process as claimed in claim 13, wherein the simulation process further comprises:

producing the road disturbance noise signal; and

superimposing the road disturbance noise signal to a wheel speed signal, and thereby producing the noise-superimposed wheel speed signal.

15. A rough road drive simulation apparatus for testing a vehicle motion control system, the simulation apparatus comprising:

means for setting the vehicle motion control system in a simulated virtual environment including a virtual vehicle model;

means for inputting a noise-superimposed wheel signal produced by superimposing a road disturbance noise signal to a wheel speed signal, to the vehicle motion control system in the simulated virtual environment;

means for examining a response of the vehicle motion control system to the noise-supposed wheel speed signal; and

means for adjusting a sensitivity of the vehicle motion control system so as to adjust the sensitivity of the vehicle motion control system to a desired reference value.