Estimation of Advisory Vehicle Speed For Low Curvatures Assuming Ideal Steering Behaviour
2022-01-1110
03/29/2022
- Event
- Content
- In the current scenario, the vehicle is integrated with infotainment maps and a telematics module, which provide extensive information regarding the terrain, including the radii of curvature (R). The transportation authority had imposed stringent guidelines regarding the range of advisory vehicle speeds (AVS) (e.g. [15 25] MPH for R = 18.4m), but a unique value of AVS for a definite curvature is not recommended. The maximum allowable speeds for R = 8.34m (U-turn) is 6.7m/s (15mph), whereas for R = 42.57m (cloverleaf interchange) is 11.17m/s (25mph). Also, in the existing literature, the mathematical models developed to estimate the AVS does not include all the steering parameters [speed, RRC, yaw rate, lateral acceleration]. Therefore, in this article, the concept of Ideal Steering Behavior (ISB) was proposed, and driver behaviour vector (DBV) was utilised to adapt “human-like” driving to estimate a unique AVS for a definite R. The DBV was retrieved using the 2019 Cadillac Escalade test vehicle provided by GMC and was driven by four drivers, on the test track with R = 18.4m. Thus, a simple model was developed, considering all the parameters reflecting ISB by matching the Rand empirically defined parameter vehicle curvature. A linear optimisation function was utilised to solve the developed model for ISB using the boundary limits obtained from the DBV. Thus, the AVS for the test track R = 18.4 m was estimated as 7.049 m/s, and polynomial interpolation was adopted using the three coordinates [[6.7,8.34] [7.049, 18.4], [11.17, 42.57] to estimate the unique AVS for definite R. The validation of the results was performed by comparing the roll and slip coefficients for the drivers and estimated AVS. Traversing the vehicle with the estimated AVS is safer as it falls in the range recommended by the transportation authority, reflects ISB, and augments vehicle health.
- Citation
- Jim, Y., Hay, C., Malik, H., and Evans, S., "Estimation of Advisory Vehicle Speed For Low Curvatures Assuming Ideal Steering Behaviour," SAE Technical Paper 2022-01-1110, 2022, .