autotest: loosen slowdown constraint on zigzag test

Tools/autotest/arducopter.py

@@ -2588,6 +2588,7 @@ class AutoTestCopter(AutoTest):
 
         ZIGZAG = 24
         j = 0
+        slowdown_speed = 0.3 # because Copter takes a long time to actually stop
         self.start_subtest("Conduct ZigZag test for all 4 directions")
         while j < 4:
             self.progress("## Align heading with the run-way (j=%d)##" % j)
@@ -2601,7 +2602,7 @@ class AutoTestCopter(AutoTest):
             self.set_rc(1, 1700)  # fly side-way for 20m
             self.wait_distance(20)
             self.set_rc(1, 1500)
-            self.wait_groundspeed(0, 0.20)   # wait until the copter slows down
+            self.wait_groundspeed(0, slowdown_speed)   # wait until the copter slows down
             self.progress("## Record Point A ##")
             self.set_rc(8, 1500)    # pilot always have to cross mid position when changing for low to high position
             self.set_rc(8, 1900)    # record point B
@@ -2613,23 +2614,23 @@ class AutoTestCopter(AutoTest):
                 self.set_rc(2, 1300)
                 self.wait_distance(10)
                 self.set_rc(2, 1500)    # re-centre pitch rc control
-                self.wait_groundspeed(0, 0.2)   # wait until the copter slows down
+                self.wait_groundspeed(0, slowdown_speed)   # wait until the copter slows down
                 self.set_rc(8, 1500)    # switch to mid position
                 self.progress("## auto execute vector BA ##")
                 self.set_rc(8, 1100)
                 self.wait_distance(17)  # wait for it to finish
-                self.wait_groundspeed(0, 0.2)   # wait until the copter slows down
+                self.wait_groundspeed(0, slowdown_speed)   # wait until the copter slows down
 
                 self.progress("## fly forward for 10 meter ##")
                 self.set_rc(2, 1300)    # fly forward for 10 meter
                 self.wait_distance(10)
                 self.set_rc(2, 1500)    # re-centre pitch rc control
-                self.wait_groundspeed(0, 0.2)   # wait until the copter slows down
+                self.wait_groundspeed(0, slowdown_speed)   # wait until the copter slows down
                 self.set_rc(8, 1500)    # switch to mid position
                 self.progress("## auto execute vector AB ##")
                 self.set_rc(8, 1900)
                 self.wait_distance(17)  # wait for it to finish
-                self.wait_groundspeed(0, 0.2)   # wait until the copter slows down
+                self.wait_groundspeed(0, slowdown_speed)   # wait until the copter slows down
                 i=i+1
             # test the case when pilot switch to manual control during the auto flight
             self.start_subtest("test the case when pilot switch to manual control during the auto flight")
@@ -2643,21 +2644,21 @@ class AutoTestCopter(AutoTest):
             self.set_rc(8, 1100)    # switch to low position, auto execute vector BA
             self.wait_distance(8)   # purposely switch to manual halfway
             self.set_rc(8, 1500)
-            self.wait_groundspeed(0, 0.2)   # copter should slow down here
+            self.wait_groundspeed(0, slowdown_speed)   # copter should slow down here
             self.progress("## Manual control to fly forward ##")
             self.set_rc(2, 1300)    # manual control to fly forward
             self.wait_distance(8)
             self.set_rc(2, 1500)    # re-centre pitch rc control
-            self.wait_groundspeed(0, 0.2)   # wait until the copter slows down
+            self.wait_groundspeed(0, slowdown_speed)   # wait until the copter slows down
             self.progress("## continue vector BA ##")
             self.set_rc(8, 1100)    # copter should continue mission here
             self.wait_distance(8)   # wait for it to finish rest of BA
-            self.wait_groundspeed(0, 0.2)   #wait until the copter slows down
+            self.wait_groundspeed(0, slowdown_speed)   #wait until the copter slows down
             self.set_rc(8, 1500)    # switch to mid position
             self.progress("## auto execute vector AB ##")
             self.set_rc(8, 1900)    # switch to execute AB again
             self.wait_distance(17)  # wait for it to finish
-            self.wait_groundspeed(0, 0.2)   # wait until the copter slows down
+            self.wait_groundspeed(0, slowdown_speed)   # wait until the copter slows down
             self.change_mode('LOITER')
             j=j+1