Merge pull request #529 from bitcraze/rik/ramp_supervisor_fix

Send continuous zero setpoints until landing in ramp examples

Author: gemenerik

examples/motors/multiramp.py

@@ -101,10 +101,14 @@ def _ramp_motors(self):
             if thrust >= 25000:
                 thrust_mult = -1
             thrust += thrust_step * thrust_mult
-        self._cf.commander.send_setpoint(0, 0, 0, 0)
-        # Make sure that the last packet leaves before the link is closed
-        # since the message queue is not flushed before closing
-        time.sleep(0.1)
+        for _ in range(30):
+            # Continuously send the zero setpoint until the drone is recognized as landed
+            # to prevent the supervisor from intervening due to missing regular setpoints
+            self._cf.commander.send_setpoint(0, 0, 0, 0)
+            time.sleep(0.1)
+        # Sleeping before closing the link makes sure the last
+        # packet leaves before the link is closed, since the
+        # message queue is not flushed before closing
         self._cf.close_link()
 
 

examples/motors/ramp.py

@@ -99,10 +99,14 @@ def _ramp_motors(self):
             if thrust >= 25000:
                 thrust_mult = -1
             thrust += thrust_step * thrust_mult
-        self._cf.commander.send_setpoint(0, 0, 0, 0)
-        # Make sure that the last packet leaves before the link is closed
-        # since the message queue is not flushed before closing
-        time.sleep(1)
+        for _ in range(30):
+            # Continuously send the zero setpoint until the drone is recognized as landed
+            # to prevent the supervisor from intervening due to missing regular setpoints
+            self._cf.commander.send_setpoint(0, 0, 0, 0)
+            time.sleep(0.1)
+        # Sleeping before closing the link makes sure the last
+        # packet leaves before the link is closed, since the
+        # message queue is not flushed before closing
         self._cf.close_link()