Files
RBF_NeuralNetwork/Book2222_controller.m
T
2021-01-04 10:31:19 +08:00

87 lines
2.6 KiB
Matlab

function [sys,x0,str,ts] = Book2222_controller(t,x,u,flag)
% 基于梯度下降法的RBF神经网络逼近
switch flag
case 0 %初始化
[sys,x0,str,ts]=mdlInitializeSizes;
case {1,2,4,9} %离散状态计算,下一步仿真时刻,终止仿真设定
sys=[];
case 3 %输出信号计算
sys=mdlOutputs(t,x,u);
otherwise
DAStudio.error('Simulink:blocks:unhandledFlag', num2str(flag));
end
function [sys,x0,str,ts]=mdlInitializeSizes %系统的初始化
sizes = simsizes;
sizes.NumContStates = 0; %设置系统连续状态的变量
sizes.NumDiscStates = 0; %设置系统离散状态的变量
sizes.NumOutputs = 1; %设置系统输出的变量
sizes.NumInputs = 2; %设置系统输入的变量
sizes.DirFeedthrough = 1; %如果在输出方程中显含输入变量u,则应该将本参数设置为1
sizes.NumSampleTimes = 0; % 模块采样周期的个数
% 需要的样本时间,一般为1.
% 猜测为如果为n,则下一时刻的状态需要知道前n个状态的系统状态
sys = simsizes(sizes);
x0 = []; % 系统初始状态变量
str = []; % 保留变量,保持为空
ts = []; % 采样时间[t1 t2] t1为采样周期,如果取t1=-1则将继承输入信号的采样周期;参数t2为偏移量,一般取为0
% 权值初值的选择
% 神经网络PID控制器 2-5-1结构
global W_new W_past C_new C_past B_new B_past
C_new = [-1 -0.5 0 0.5 1;
-10 -5 0 5 10]; %2*5 中心矢量
C_past = C_new;
B_new = [3 3 3 3 3]; %1*5 基宽度参数
B_past = B_new;
W_new = rand(1,5); %权值取0-1的随机值
W_past = W_new;
function sys = mdlOutputs(t,x,u) %产生(传递)系统输出
global W_new W_past C_new C_past B_new B_past
alpha = 0.05; %惯性系数
xite = 0.15; %学习效率
u_in = u(1);
y_out = u(2);
some = [u_in; y_out];
h = zeros(5,1);
for j = 1:5
h(j) = exp(-(norm(some - C_new(:,j))^2/(2* B_new(j)^2))); %5*1矩阵 径向基函数
end
% RBF的网络输出ym
ym = W_new * h;
% 权值的调整 更新值
deltaW = zeros(1,5);
for i = 1:5
deltaW(i) = xite * (y_out - ym) * h(i);
end
for i = 1:5
W_new(i) = W_new(i) + deltaW(i) + alpha*(W_new(i) - W_past(i));
end
% 基宽带参数b的修正
deltab = zeros(1,5);
for i = 1:5
deltab(i) = xite * (y_out - ym) * W_new(i) * h(i) * (norm(some - C_new(:,i))^2 / B_new(i)^3);
B_new(i) = B_new(i) + deltab(i) + alpha*(B_new(i) - B_past(i));
end
% 中心矢量c的修正
deltac = zeros(2,5);
for j = 1:2
for i = 1:5
deltac(j,i) = xite * (y_out - ym) * W_new(i) * h(i) * ((some(j) - C_new(j,i)) / B_new(i)^2);
C_new(j,i) = C_new(j,i) + deltac(j,i) + alpha*(C_new(j,i) - C_past(j,i));
end
end
sys(1) = ym;
W_past = W_new;
B_past = B_new;
C_past = C_new;