Page - 20 - in Integration of Advanced Driver Assistance Systems on Full-Vehicle Level - Parametrization of an Adaptive Cruise Control System Based on Test Drives

2. Adaptive Cruise Control Table 2.1.: Simulation input simulation num. v0 [km/h] δf [°] 1 50 2.03 2 60 1.45 3 70 1.09 4 80 0.86 5 90 0.71 6 100 0.59 7 110 0.51 simulation num. v0 [km/h] δf [°] 8 120 0.45 9 130 0.40 10 140 0.36 11 150 0.33 12 160 0.30 13 160 0.00 vset,min = 7m/s, and the maximum lateral acceleration vay,max = 2.3m/s 2. Using this data, simulations with a simplified vehicle dynamics model of eq. (B.17) were con- ducted. The initial vehicle speed was increased from v0 = 50 to 160km/h. The target vehicle was driving at vT =vset,min. Using the script of Hirschberg [HW10], the steering angle of the front tyre was calculated by δf = lf+ lr v20 vay,max + may,max lf+ lr ( lr 2fcy − lf 2rcy ) (2.11) and was held constant during each simulation. Thereby, lf and lr are the front and rear axle distances to the Center of Gravity (CG),m equals the overall vehicle mass, and fcy and rcy are the side stiffnesses of one front and one rear tyre. Figure 2.13(a) shows the output of the simulation. During the simulation, the vehicle decelerated withax,min until v≤ vT, indicated with the triangle in fig. 2.13(a). The squares indicate the point where the vehicle has to detect the traget to have a final distance of ∆s= vT τset+s0 to the target. The time gap was set to τset = 1s, and the final stopping distance to s0 = 2m. The same simulations were performed according to standard ISO 22179 [Tec09], describing Stop-and-Go Adaptive Cruise Control (FSRA) systems. Only the target speed was set tovT = 0, and the maximum deceleration was defined as a function of the vehicle speed, as depicted in fig. 2.12. The complete list of inputs for the 13 simulations is shown in table 2.1. Additionally, the FOV of the production RADAR sensor ARS 308 of Continental [LSKW10] is added in both graphs, representing the FOV at the time when the ACC vehicle begins to decelerate. This sensor was chosen because it is an example of a currently used RADAR sensor in an ACC-equipped vehicle. In the simulation, the system successfully handles a situation if the square is within the detection range of the sensor. This means that the target is within the FOV when the vehicle begins to decelerate. For ACC-equipped vehicles, this is possible up to an initial vehicle speed ofv0 = 150km/h. For FSRA systems, the highest initial velocity for which the situation was adequately handled is in simulation 4 at v0 = 80km/h. This approach canbeusedtofindthedesiredFOVforanACCsystemaccording to setoperation limits. 20