function draw_pend(y,m,M,L)
x = y(1);
th = y(3);

% kinematics
% x = 3;        % cart position
% th = 3*pi/2;   % pendulum angle

% dimensions
% L = 2;  % pendulum length
W = 1*sqrt(M/5);  % cart width
H = .5*sqrt(M/5); % cart height
wr = .2; % wheel radius
mr = .3*sqrt(m); % mass radius

% positions
% y = wr/2; % cart vertical position
y = wr/2+H/2; % cart vertical position
w1x = x-.9*W/2;
w1y = 0;
w2x = x+.9*W/2-wr;
w2y = 0;

px = x + L*sin(th);
py = y + L*cos(th);

plot([-10 10],[0 0],'k','LineWidth',2)
hold on
rectangle('Position',[x-W/2,y-H/2,W,H],'Curvature',.1,'FaceColor',[.5 0.5 1],'LineWidth',1.5)
rectangle('Position',[w1x,w1y,wr,wr],'Curvature',1,'FaceColor',[0 0 0],'LineWidth',1.5)
rectangle('Position',[w2x,w2y,wr,wr],'Curvature',1,'FaceColor',[0 0 0],'LineWidth',1.5)

plot([x px],[y py],'k','LineWidth',2)

rectangle('Position',[px-mr/2,py-mr/2,mr,mr],'Curvature',1,'FaceColor',[1 0.1 .1],'LineWidth',1.5)

% set(gca,'YTick',[])
% set(gca,'XTick',[])
xlim([-5 5]);
ylim([-2 2.5]);
axis equal
%set(gcf,'Position',[100 550 1000 400])
% box off
drawnow
hold off