diff --git a/simulator.py b/simulator.py
index 514d89c..e9b0a51 100755
--- a/simulator.py
+++ b/simulator.py
@@ -40,6 +40,7 @@ class Simulator:
         while True:
             try:
                 self.s, _ = self.s.accept()
+                self.s.setblocking(False)
                 break
             except BlockingIOError:
                 print("Waiting for connection")
@@ -141,7 +142,7 @@ class NaiveSimulator(Simulator, Douche):
         self.last_update = lt
         gamma = self.G*(self.command_spd - self.speed)
 
-        self.speed += 1./self.J * (self.G - self.f*self.speed ) * self.time_step
+        self.speed += 1./self.J * (gamma - self.f*self.speed ) * self.time_step
         self.pos += self.speed * self.time_step
 
         self.steps = np.ceil(self.pos * np.array([self.X_STEPS_PER_MM,