function [YT,TARGETSTIFF] = setTarget(t,YT,TARGETSTIFF,NIBS,Starget,demonumber);
%
% set target point locations at each time t
%
% inputs:
%     t:            current time           
%     YT:           current target point locations
%     TARGETSTIFF:  current target link stiffnesses
%     NIBS:         numbers of IB points in each IB object
%     Starget:      stiffness for target links
%     demonumber:   which demo was chosen

% outputs:
%     YT:           new target point locations 
%     TARGETSTIFF:  new target link stiffnesses
%

if demonumber==3,
%
% IB object 1 is bottom wall
% IB object 2 is top    wall
% IB object 3 is circle
% Only  objects 1 and 2 have target points
% IB objects 1 and 2 have the same number of IB points
%
N = NIBS(1);
ytopwall    = 0.75;
ybottomwall = 0.25;
V   = 1.0;
T   = 0.2;
Amp = 0.25;
for k=1:N,
    j = N+k;      
    yone = YT(k,1);
    if V*t >= yone & yone >= V*(t-T),
       YT(k,2) = ybottomwall + Amp*sin( pi*(t - (yone/V))/T);
       YT(j,2) = ytopwall    - Amp*sin( pi*(t - (yone/V))/T);
    else
       YT(k,2) = ybottomwall;
       YT(j,2) = ytopwall;
    end
end
end