Common: Mateksys OptFlow 3901-L0X

common/source/docs/common-mateksys-optflow-3901L0X.rst

@@ -0,0 +1,58 @@
+.. _common-mateksys-optflow-3901L0X:
+
+==============================
+MatekSys Optical Flow 3901-L0X
+==============================
+
+[copywiki destination="copter,plane,rover"]
+
+The `MatekSys optical flow 3901-L0X sensor <http://www.mateksys.com/?portfolio=3901-l0x>`__ is a lightweight optical flow sensor including a short range lidar which uses the MSP protocol to communicate with the autopilot.  This can be used to improve horizontal position control especially in GPS denied environments.
+
+.. image:: ../../../images/mateksys-opticalflow-3901L0X.jpg
+   :target: ../_images/mateksys-opticalflow-3901L0X.jpg
+   :width: 450px
+
+.. warning::
+
+   The lidar included with the sensor is very short range especially outdoors.  We strongly recommend using a :ref:`longer range lidar instead <common-rangefinder-landingpage>`.
+
+Where to Buy
+------------
+
+The sensor is available from `Matekesys resellers <http://www.mateksys.com/?page_id=1212>`__
+
+Connection to Autopilot
+-----------------------
+
+.. image:: ../../../images/mateksys-opticalflow-3901L0X-autopilot.jpg
+   :target: ../_images/mateksys-opticalflow-3901L0X-autopilot.jpg
+   :width: 450px
+
+.. image:: ../../../images/mateksys-opticalflow-3901L0X-cubepilot.png
+   :target: ../_images/mateksys-opticalflow-3901L0X-cubepilot.png
+   :width: 450px
+
+- The flow sensor should be mounted on the underside of the copter with the camera lens pointing downwards.  The small arrow near the camera lens should be pointing forwards
+- Connect the sensor to one of the autopilot's serial ports (e.g. Serial2 / Telem2)
+- Set :ref:`FLOW_TYPE <FLOW_TYPE>` = 7 (MSP)
+- Set :ref:`FLOW_FXSCALER <FLOW_FXSCALER>` = -800
+- Set :ref:`FLOW_FYSCALER <FLOW_FYSCALER>` = -800
+- Set :ref:`SERIAL2_PROTOCOL <SERIAL2_PROTOCOL>` = 32 (MSP) (assuming sensor is connected to Serial2)
+- Set :ref:`SERIAL2_BAUD <SERIAL2_BAUD>` = 115 (115200 bps) (assuming sensor is connected to Serial2)
+
+To use the onboard lidar (not recommended):
+
+- Set :ref:`RNGFND1_TYPE <RNGFND1_TYPE>` = 32 (MSP)
+- Set :ref:`RNGFND1_MAX_CM <RNGFND1_MAX_CM>` = 120 to set range finder's maximum range to 1.2m
+
+Additional Notes
+-----------------
+
+- As with all optical flow sensors, a range finder is required to use the sensor for autonomous modes including :ref:`Loiter <loiter-mode>` and :ref:`RTL <rtl-mode>`
+- :ref:`FlowHold <flowhold-mode>` does not require the use of a rangefinder but performance is generally worse than Loiter mode and is not recommended
+- Performance can be improved by setting the :ref:`sensors position parameters <common-sensor-offset-compensation>`.  For example if the sensor is mounted 2cm forward and 5cm below the frame's center of rotation set :ref:`FLOW_POS_X <FLOW_POS_X>` to 0.02 and :ref:`FLOW_POS_Z <FLOW_POS_Z>` to 0.05.
+
+Testing and Setup
+-----------------
+
+See :ref:`common-optical-flow-sensor-setup`

common/source/docs/common-optical-flow-sensors-landingpage.rst

@@ -17,6 +17,7 @@ Select the links below for information on the available sensors.
     ARK Flow <common-arkflow>
     Cheerson CX-OF <common-cheerson-cxof>
     HereFlow <common-hereflow>
+    Mateksys 3901-L0X <common-mateksys-optflow-3901L0X>
     OpenMV <common-openmv-optflow>
     PX4FLOW <common-px4flow-overview>
     UPixels UPFlow <common-upixels-upflow>