Open dajiba6 opened 5 days ago
double PathOptimizerUtil::EstimateJerkBoundary(const double vehicle_speed) {
const auto& veh_param =
common::VehicleConfigHelper::GetConfig().vehicle_param();
const double axis_distance = veh_param.wheel_base();
const double max_yaw_rate =
veh_param.max_steer_angle_rate() / veh_param.steer_ratio();
return max_yaw_rate / axis_distance / vehicle_speed;
}
2. problem
thank you my friend, but i still confused about the second question. Isn't the delta_t already included by vehiclespeed? $$\frac{d^3l}{ds^3}=\frac{d\frac{d^2l}{ds^2}}{dt}\cdot\frac{dt}{ds}$$ $$\frac{d^2l}{ds^2}\approx\kappa-\kappa{ref}=\frac{tan(\alpha)}{L}-\kappa{ref}\approx\frac{\alpha}{L}-\kappa{ref}$$ $$\frac{d^3l}{ds^3}=\frac{\alpha'}{Lv}<\frac{\alpha'_{max}}{Lv}$$
The variable delta_t is unrelated to delta_s. Below is the discretized formula incorporating a deltas into the jerk bound: $$l{n}^{'''}=\frac{l{n}^{''}-l{n-1}^{''}}{\Delta s}<\frac{\alpha{max}^{'}}{Lv}$$ It should be noted that the jerk bound is applied to $l^{''}$, indicating that the actual bound set in the piecewise jerk problem corresponds to the right-hand side of the inequality presented below: $$l{n}^{''}-l{n-1}^{''}<\Delta s\frac{\alpha{max}^{'}}{Lv}$$
The variable delta_t is unrelated to delta_s. Below is the discretized formula incorporating a delta_s into the jerk bound: ln‴=ln″−ln−1″Δs<αmax′Lv It should be noted that the jerk bound is applied to l″, indicating that the actual bound set in the piecewise jerk problem corresponds to the right-hand side of the inequality presented below: ln″−ln−1″<Δsαmax′Lv
OMG, you are so niubi. Thank you my friend, it really helps. Can I add your wechat to chat chat.
Why should the maximum steering angle rate be divided by an additional 2 when calculating the dddx bound? Is it for safety margin considerations? Why should dddx be multiplied by an additional delta_s when placed in the boundary matrix?