autotest: add rate thread autotest

Tools/autotest/arducopter.py

@@ -6180,6 +6180,77 @@ def DynamicRpmNotches(self):
         if ex is not None:
             raise ex
 
+    def DynamicRpmNotchesRateThread(self):
+        """Use dynamic harmonic notch to control motor noise via ESC telemetry."""
+        self.progress("Flying with ESC telemetry driven dynamic notches")
+
+        self.set_rc_default()
+        self.set_parameters({
+            "AHRS_EKF_TYPE": 10,
+            "INS_LOG_BAT_MASK": 3,
+            "INS_LOG_BAT_OPT": 0,
+            "INS_GYRO_FILTER": 300, # set gyro filter high so we can observe behaviour
+            "LOG_BITMASK": 958,
+            "LOG_DISARMED": 0,
+            "SIM_VIB_MOT_MAX": 350,
+            "SIM_GYR1_RND": 20,
+            "SIM_ESC_TELEM": 1,
+            "FLIGHT_OPTIONS": 8
+        })
+        self.reboot_sitl()
+
+        self.takeoff(10, mode="ALT_HOLD")
+
+        # find a motor peak, the peak is at about 190Hz, so checking between 50 and 320Hz should be safe.
+        # there is a second harmonic at 380Hz which should be avoided to make the test reliable
+        # detect at -5dB so we don't pick some random noise as the peak. The actual peak is about +15dB
+        freq, hover_throttle, peakdb = self.hover_and_check_matched_frequency_with_fft(-5, 50, 320)
+
+        # now add a dynamic notch and check that the peak is squashed
+        self.set_parameters({
+            "INS_LOG_BAT_OPT": 4,
+            "INS_HNTCH_ENABLE": 1,
+            "INS_HNTCH_FREQ": 80,
+            "INS_HNTCH_REF": 1.0,
+            "INS_HNTCH_HMNCS": 5, # first and third harmonic
+            "INS_HNTCH_ATT": 50,
+            "INS_HNTCH_BW": 40,
+            "INS_HNTCH_MODE": 3,
+            "FLIGHT_OPTIONS": 8
+        })
+        self.reboot_sitl()
+
+        # -10dB is pretty conservative - actual is about -25dB
+        freq, hover_throttle, peakdb1, psd = \
+            self.hover_and_check_matched_frequency_with_fft_and_psd(-10, 50, 320, reverse=True, instance=2)
+        # find the noise at the motor frequency
+        esc_hz = self.get_average_esc_frequency()
+        esc_peakdb1 = psd["X"][int(esc_hz)]
+
+        # now add notch-per motor and check that the peak is squashed
+        self.set_parameter("INS_HNTCH_OPTS", 2)
+        self.reboot_sitl()
+
+        freq, hover_throttle, peakdb2, psd = \
+            self.hover_and_check_matched_frequency_with_fft_and_psd(-10, 50, 320, reverse=True, instance=2)
+        # find the noise at the motor frequency
+        esc_hz = self.get_average_esc_frequency()
+        esc_peakdb2 = psd["X"][int(esc_hz)]
+
+        # notch-per-motor will be better at the average ESC frequency
+        if esc_peakdb2 > esc_peakdb1:
+            raise NotAchievedException(
+                "Notch-per-motor peak was higher than single-notch peak %fdB > %fdB" %
+                (esc_peakdb2, esc_peakdb1))
+
+        # check that the noise is being squashed at all. this needs to be an aggresive check so that failure happens easily
+        # testing shows this to be -58dB on average
+        if esc_peakdb2 > -25:
+            raise NotAchievedException(
+                "Notch-per-motor had a peak of %fdB there should be none" % esc_peakdb2)
+
+        self.reboot_sitl()
+
     def hover_and_check_matched_frequency(self, dblevel=-15, minhz=200, maxhz=300, fftLength=32, peakhz=None):
         '''do a simple up-and-down test flight with current vehicle state.
         Check that the onboard filter comes up with the same peak-frequency that
@@ -11352,6 +11423,7 @@ def tests2b(self):  # this block currently around 9.5mins here
             Test(self.DynamicNotches, attempts=4),
             self.PositionWhenGPSIsZero,
             self.DynamicRpmNotches, # Do not add attempts to this - failure is sign of a bug
+            self.DynamicRpmNotchesRateThread,
             self.PIDNotches,
             self.RefindGPS,
             Test(self.GyroFFT, attempts=1, speedup=8),