Differences

This shows you the differences between two versions of the page.

--- searchwing-ardupilot-parameters [2020/02/27 10:49]
beckmanf [Servo settings] adapted to KURDI
+++ searchwing-ardupilot-parameters [2022/05/23 14:29]
wf68spef [Ardupilot Parameter Setup]
@@ Line 1: / Line 1: @@
 ====== Ardupilot Parameter Setup ======
-[[https://ardupilot.org/plane/docs/parameters-Plane-stable-V4.0.3.html|Description of the parameters]]
+[[https://ardupilot.org/plane/docs/parameters-Plane-stable-V4.2.0.html|Ardupilot description of the parameters]]
+[[https://gitlab.com/searchwing/operational/searchwing-config/-/blob/master/ardupilot/searchwing/LATEST.params|Standard set of SearchWing ArduPilot parameters]]
 ==== Arming / Safety ====
@@ Line 8: / Line 10: @@
 |BRD_SAFETYENABLE   |0           |Disable the safety switch   |Safety switch is not accessible, because it is inside the fuselage |
 |ARMING_RUDDER      |2           |Arm and Disarm with rudder  |Default is that you can only arm but not disarm with rudder |
-|BRD_SAFETY_MASK    |15          |Servo 1,2,3,4 enabled       |These servos can move also in safe state - NOT REQUIRED??? |
+|BRD_SAFETY_MASK    |27          |Servo 1,2,4,5 enabled       |These servos can move also in safe state - NOT REQUIRED??? |
 |INS_GYRO_CAL       |0           |Disable Gyro Calibration at startup       | This prevents INS calibration at startup|
 |ARSPD_TYPE         |0           |No Airspeed Pitot Tube      | Disable the Pitottube airspeed sensor (we don't have one)|
+|COMPASS_USE2       |0           |Disable PixRacer compass    | Disable the PixRacer internal compass |
+|COMPASS_USE3       |0           |Disable PixRacer compass    | Disable the PixRacer internal compass |
 Is the safety_mask maybe not required because the pixracer is always in safe state? Safe and disarmed is different?
@@ Line 39: / Line 42: @@
 ^Parametername      ^Value       ^Description                 ^Remark  ^
-|MIXING_GAIN        |1.0         |Mixing of pitch and rudder to vtail |Default is 0.5 - full pitch will yield only 50 percent of vtail servo output |
+|MIXING_GAIN        |0.75        |Mixing of pitch and rudder to vtail |Default is 0.5 - full pitch will yield only 50 percent of vtail servo output |
@@ Line 57: / Line 60: @@
 ^Parametername      ^Value       ^Description                 ^Remark  ^
 |SERIAL2_BAUD       |9           |9600 Baud |reduced to 9600 as otherwise no wifi with MAVESP connection possible |
-|SERIAL2_PROTOCOL   |1           |MAVLink1 |Only MAVLink1 works for pymavlink on pi |
+|SERIAL2_PROTOCOL   |2           |MAVLink2 | Mavlink2 needed for PLAY_TUNE |
+|SR2_RAW_SENS       |0           |0 Hz |no raw data needed |
+|SR2_EXT_STAT       |1           |1 Hz | |
+|SR2_RC_CHAN        |0           |0 Hz | |
+|SR2_RAW_CTRL       |0           |0 Hz | |
+|SR2_POSITION       |5           |5 Hz | Contains GLOBAL_POSITION_INT, LOCAL_POSITION_NED messages |
+|SR2_EXTRA1       |5           |5 Hz | Contains ATTITUDE message |
+|SR2_EXTRA2       |0           |0 Hz |  |
+|SR2_EXTRA3       |1           |1 Hz | Contains SYSTEM_TIME message |
+|SR2_PARAMS       |0           |0 Hz |  |
+|SR2_ADSB         |0           |0 Hz | |
+===== Logging =====
+Several bits can be set for logging of different informations: [[https://ardupilot.org/plane/docs/parameters.html#log-bitmask-log-bitmask|Log Bitmask Description]]
+Enabled all (''==65535'') results in following per message data sum in bytes for a 20 minute flight:
+{{ ::average_log_msg_sizes.png?1400 |}}
+  * The PID, NKF(EKF) and IMU take a lot of space.
+  * The PID and EKF is saved using the "attitude" bit in the logging parameter setting (see [[https://github.com/ArduPilot/ardupilot/blob/6af0f460afa6f51c41056cd25fe2c70164d9d460/ArduPlane/Log.cpp#L39|Code]]). For the attitude two settings are available: Fast (50Hz), Medium(10Hz) according to [[https://github.com/ArduPilot/ardupilot_wiki/blob/6c81c28126e6cb2bdbb9cb58291342ca3ade96a0/dev/source/docs/using-the-command-line-interpreter-to-configure-apmcopter.rst#reading-logs-through-the-cli|LINK]]. I think 10Hz could be enough for us. __**But in the Code actually the Logging is done with 25Hz**__ (see [[https://github.com/ArduPilot/ardupilot/blob/d8d3494b170d50f7b45dced928cd5d9150b50d2f/ArduPlane/ArduPlane.cpp#L87|Code]])
+  * IMU logging **could be disabled,** as its already triggerd by attitude logging anyway (see [[https://github.com/ArduPilot/ardupilot/blob/d8d3494b170d50f7b45dced928cd5d9150b50d2f/ArduPlane/ArduPlane.cpp#L209|Code]]), but with less data amount. **UPDATE:** Actually IMU also loggs the **BARO**, so it should not be disabled (see [[https://github.com/ArduPilot/ardupilot/search?q=set_log_baro_bit|INFO]].
+  * TECS (Total Energy Control System) controls altitude vs speed and is important and **should be enabled**.
+  * CTUN Logs contain baro and ** should be enabled.**
+  * NTUN Logs navigation tuning info at 10 Hz and ** should  be enabled.**
+This results in the following Table (according to [[https://ardupilot.org/plane/docs/parameters.html#log-bitmask-log-bitmask|Log Bitmask Description]]):
+^ Bit 	^ Meaning    ^ Enabled ^
+| 0 | ATTITUDE_FAST(50Hz) | OFF |
+| 1 | ATTITUDE_MED(10Hz) | ON |
+| 2 | GPS | ON |
+| 3 | PM | ON |
+| 4 | CTUN | ON |
+| 5 | NTUN | ON |
+| 6 | MODE | ON |
+| 7 | IMU | ON |
+| 8 | CMD | ON |
+| 9 | CURRENT | ON |
+| 10 | COMPASS | ON |
+| 11 | TECS | ON |
+| 12 | CAMERA | OFF |
+| 13 | RC | ON |
+| 14 | SONAR | OFF |
+| 15 | ARM/DISARM | ON |
+| 19 | IMU_RAW | OFF |
+| 20 | ATTITUDE_FULLRATE | OFF |
+This results into the following parameter values. In the remarks you can see empirical Results for some settings from ArduPlane Simulator.
+^Parametername      ^Value       ^Description                 ^Remark  ^
+|LOG_BITMASK       |  65535          | Log all    |     ~3.04 MB/Min Log          |
+|LOG_BITMASK       |  45054          | Log from table above (IMU disabled) |     TODO       |
+|LOG_BITMASK       |  TODO          | Log from table above (IMU enabled) |     TODO        |
+|LOG_BITMASK       |  2              | Log only attitude Medium |     ~1.75 MB/Min Log         |
 ===== MAVESP8266 Wifi Telemetry =====
@@ Line 68: / Line 128: @@
-	1	BATT_AMP_PERVLT	36.000000000000000000	9
+	1	BATT_AMP_PERVLT	24.0	9
+	1	BATT_AMP_OFFSET	-0.07	9
 	1	BATT_CURR_PIN	3	2
 	1	BATT_MONITOR	4	2
 	1	BATT_SERIAL_NUM	-1	6
-	1	BATT_VOLT_MULT	10.207025527954101563	9
+	1	BATT_VOLT_MULT	10.213	9
 	1	BATT_VOLT_PIN	2	2
 	1	BATT_WATT_MAX	0	4
+===== RPM =====
+To measure the RPM of the motor we can use a BACK-EMF Measurement from 2 of the 3 motorcables. For more info check out the page:
+https://www.hobbywingdirect.com/products/rpm-sensor
+We connected the output pins to a AUX pin of the FC. Check out the info from Ardupilot for some info regarding the following config:
+https://ardupilot.org/copter/docs/common-rpm.html
+^Parametername      ^Value       ^Description                 ^Remark  ^
+|RPM_MAX	|100000.000000000000000000	| | |
+|RPM_MIN	|10.000000000000000000	| | |
+|RPM_MIN_QUAL	|0.100000001490116119	| | |
+|RPM_PIN	|Pin	| PIN | depending on FC |
+|RPM_SCALING	|0.143	|  | check the hints below for this setting |
+|RPM_TYPE	|2	| AUX | Type needs to be AUX to calc using the given sensor |
+The RPM in general can be calculated using the formula from https://www.radiocontrolinfo.com/brushless-motor-efficiency/measuring-motor-rpm/ :
+''RPM = ( 120 x Frequency ) / # of Motor Poles''
+Thats because:
+''The AC current that is produced alternates each time 2 magnetic poles pass by a winding in the stator.
+''
+As Ardupilot measures the periode duration ''dt_avg'' of the sensor rectangular signal, and calculates the RPM using
+''float rpm = scaling * (1.0e6 / dt_avg) * 60;''
+the scaling needs to correct this using
+''SCALING = ( 1 / # of Motor Poles ) * 2''
+For the Extron 800KV Motor , we have 14 Poles.
 ===== Tuning =====
@@ Line 95: / Line 195: @@
 If min groundspeed is net met, plane increases throttle
-	1	NAVL1_DAMPING	0.600000023841857910	9
+	1	NAVL1_DAMPING	0.800000023841857910	9
-	1	NAVL1_PERIOD	10.000000000000000000	9
+	1	NAVL1_PERIOD	17.000000000000000000	9
-TBD!
+This is the default value for NAVL1 (Beck, 27.2.20)
 	1	PTCH2SRV_RLL	1.299999952316284180	9
@@ Line 106: / Line 206: @@
 	1	TECS_CLMB_MAX	6.500000000000000000	9
 	1	TECS_SINK_MAX	5.000000000000000000	9
-	1	TECS_SPDWEIGHT	1.000000000000000000	9 #TBD!
-Height is more important than speed
-SPDWEIGHT - Setting it to 0.0 will cause the pitch control to control height and ignore speed errors. This will normally improve height accuracy but give larger airspeed errors.
-	1	WP_LOITER_RAD	40	4
+	1	WP_LOITER_RAD	60	4
-	1	WP_RADIUS	25	4
+	1	WP_RADIUS	90	4
-TBD; should increase precission
+WP settings are set to default (Beck, 27.2.20)
 # Modes Setup (Special Switches)
 to be done.