From 5dbf85d356e39fae63ac65dc87f578783e44e692 Mon Sep 17 00:00:00 2001 From: Veronika Neumann Date: Fri, 22 Nov 2024 15:45:20 +0100 Subject: [PATCH] PID Control added --- doc/research/paf24/planning/ACC.md | 15 +++++++++++++-- 1 file changed, 13 insertions(+), 2 deletions(-) diff --git a/doc/research/paf24/planning/ACC.md b/doc/research/paf24/planning/ACC.md index 1a3474f3..ac8a8747 100644 --- a/doc/research/paf24/planning/ACC.md +++ b/doc/research/paf24/planning/ACC.md @@ -1,5 +1,7 @@ # ACC +This file gives a general overview on possible ACC implementations and reflects the current state of the ACC. + ## General The main goal of an ACC (Adaptive Cruise Control) is to follow a car driving in front while keeping a safe distance to it. This can be achieved by adjusting the speed to the speed of the car in front. @@ -8,6 +10,15 @@ There are basically three different techniques that can be used to implement an ### PID Control +The PID Controller consists of three terms: the proportional term, the integral term and the derivative term. One possible simple controller model looks as follows: + +$$ v_f(t) = v_f(t - t_s) + k_p e (t-t_s) + k_d \dot{e}(t - t_s) $$ +$$ e(t-t_s) = \Delta x(t - t_s) - t_{hw,d} v_f (t - t_s) $$ + +- $t_s$: sampling time +- $k_p$ and $k_d$: coefficients for proportional and derivative terms +- $e$: distance error (difference between actual distance $\Delta x$ and desired distance $\Delta x_d$) + ### Model Predictive Control (MPC) It calculates the current control action by solving an online, iterative and finite-horizon optimization of the model. @@ -32,7 +43,7 @@ Provides a unified control framework to offer both functions: ACC and Stop & Go. - Which output should be transfered to the Acting component? Only the desired speed? - Which input do we get from the Perception component? The distance and velocity of the car in front? -## ACC Algorithm +## ACC in our project ### Current implementation @@ -86,4 +97,4 @@ Start implementing safety distance and general target speed logic. Subscriber lo ## Sources -[ACC](https://www.researchgate.net/publication/335934496_Adaptive_Cruise_Control_Strategies_Implemented_on_Experimental_Vehicles_A_Review) +[He, Yinglong et al. (2019). Adaptive Cruise Control Strategies Implemented on Experimental Vehicles: A Review. IFAC-PapersOnLine. 52. 21-27. 10.1016/j.ifacol.2019.09.004. ](https://www.researchgate.net/publication/335934496_Adaptive_Cruise_Control_Strategies_Implemented_on_Experimental_Vehicles_A_Review)