autotest: added --wind option to sim_quad

this is in the form of speed,direction,turbulance

Tools/autotest/pysim/aircraft.py

@@ -36,6 +36,8 @@ class Aircraft(object):
         self.gravity = 9.8 # m/s/s
         self.accelerometer = euclid.Vector3(0, 0, -self.gravity)
 
+        self.wind = util.Wind('0,0,0')
+
     def normalise(self):
         '''normalise roll, pitch and yaw
 

Tools/autotest/pysim/quadcopter.py

@@ -74,6 +74,9 @@ class QuadCopter(Aircraft):
         accel3D += euclid.Vector3(0, 0, -self.gravity)
         accel3D += air_resistance
 
+        # add in some wind
+        accel3D += self.wind.accel(self.velocity)
+
         # new velocity vector
         self.velocity += accel3D * delta_time
         self.accel     = accel3D

Tools/autotest/pysim/sim_quad.py

@@ -84,6 +84,7 @@ parser.add_option("--simin",  dest="simin",   help="SIM input (IP:port)",
 parser.add_option("--simout", dest="simout",  help="SIM output (IP:port)",      default="127.0.0.1:5501")
 parser.add_option("--home", dest="home",  type='string', default=None, help="home lat,lng,alt,hdg (required)")
 parser.add_option("--rate", dest="rate", type='int', help="SIM update rate", default=1000)
+parser.add_option("--wind", dest="wind", help="Simulate wind (speed,direction,turbulance)", default='0,0,0')
 
 (opts, args) = parser.parse_args()
 
@@ -141,7 +142,7 @@ a.altitude = a.home_altitude
 a.yaw = float(v[3])
 a.ground_level = a.home_altitude
 a.position.z = 0
-
+a.wind = util.Wind(opts.wind)
 
 print("Starting at lat=%f lon=%f alt=%.1f heading=%.1f" % (
     a.home_latitude,