vehicle.m

用于汽车巡航控制系统的模糊控制算法

function [v] = Vehicle(theta, v, grade, dt, alpha, gamma, Fi, m)

% function [v] = Vehicle(theta, v, grade, dt, alpha, gamma, Fi, m)
% Vehicle simulation.
% Based on page 186 in the text "Fuzzy Logic," by Yen and Langari.
% This m-file simulates a single discrete time step.

% INPUTS
%   theta = throttle position (radians)
%   v = vehicle speed (meters/sec)
%   grade = road grade (radians)
%   dt = simulation step size (seconds)
%   alpha = drag coefficient (Newtons / (meters/sec)^2, typically about 4)
%   gamma = engine force coefficient (Newtons, typically about 12500)
%   Fi = engine idle force (Newtons, typically about 1000)
%   m = vehicle mass (kilograms, typically about 1000)
% OUTPUTS
%   v = vehicle speed (meters/sec)

Fe1 = Fi + gamma * sqrt(theta);
Fd = alpha * v * v * sign(v);
Fg = m * 9.81 * sin(grade);
vdot = (Fe1 - Fd - Fg) / m;
v = v + vdot * dt;