Problem fonction while in Simulink

Hello i'm student and i need to programm the speed of a motor for calculate a battery's autonomy. My motor need to accelerate in first time(to pass 20km/h at 50 mk/h), to stay during 4 sec at 50 km/h, to decelerate to 20 km/h in third time, and for finish to stay during 4 sec at 20km/h. But i don't arrive to simule this in a programm and repeat it until my battery's autonmy pass under 0.2 (20%). If you can help me, i test to do this in matlab function (Simulink)

function u = fonc(a,b,c,d,e)
%u=motor speed
%a=50 km/h
%b=20 km/h
%c=braking time
%d=clock
%e=pourcent of my battery
a=a/3.6/0.2032; %rad/s
b=b/3.6/0.2032; %rad/s
f=(a-b)/c;
while e>0.2
  if d<c
      u=b+(f*d);
  end
  if u>a
      u=a;
  end
  if d>8
      u=a-(f*(d-8);
  end
  if u<b
      u=b;
  end
end

Answer 1

[Azzi Abdelmalek]

If e>0.2, you will have an infinite while loop.