Merge pull request #671 from PX4/param_docs

Parameter documentation enhancements

18 files changed, 780 insertions, 174 deletions

diff --git a/Tools/px4params/.gitignore b/Tools/px4params/.gitignore
index 5d0378b4a..d78b71a6e 100644
--- a/Tools/px4params/.gitignore
+++ b/Tools/px4params/.gitignore
@@ -1,3 +1,4 @@
 parameters.wiki
 parameters.xml
+parameters.wikirpc.xml
 cookies.txt
\ No newline at end of file
diff --git a/Tools/px4params/dokuwikiout.py b/Tools/px4params/dokuwikiout.py
deleted file mode 100644
index c5cf65ea6..000000000
--- a/Tools/px4params/dokuwikiout.py
+++ /dev/null
@@ -1,62 +0,0 @@
-import output
-from xml.sax.saxutils import escape
-
-class DokuWikiOutput(output.Output):
-    def Generate(self, groups):
-        pre_text = """<?xml version='1.0'?>
-            <methodCall>
-              <methodName>wiki.putPage</methodName>
-                  <params>
-              <param> 
-                <value>
-                  <string>:firmware:parameters</string>
-                </value>
-              </param> 
-                  <param> 
-                <value>
-                  <string>"""
-        result = "====== Parameter Reference ======\nThis list is auto-generated every few minutes and contains the most recent parameter names and default values."
-        for group in groups:
-            result += "==== %s ====\n\n" % group.GetName()
-            result += "|< 100% 20% 20% 10% 10% 10% 30%>|\n"
-            result += "^ Name            ^ Description    ^ Min    ^ Max    ^ Default   ^ Comment    ^\n"
-            for param in group.GetParams():
-                code = param.GetFieldValue("code")
-                name = param.GetFieldValue("short_desc")
-                name = name.replace("\n", "")
-                result += "| %s   | %s  " % (code, name)
-                min_val = param.GetFieldValue("min")
-                if min_val is not None:
-                    result += " | %s  " % min_val
-                else:
-                    result += " | "
-                max_val = param.GetFieldValue("max")
-                if max_val is not None:
-                    result += " | %s  " % max_val
-                else:
-                    result += " | "
-                def_val = param.GetFieldValue("default")
-                if def_val is not None:
-                    result += "| %s  " % def_val
-                else:
-                    result += " | "
-                long_desc = param.GetFieldValue("long_desc")
-                if long_desc is not None:
-                    long_desc = long_desc.replace("\n", "")
-                    result += "| %s  " % long_desc
-                else:
-                    result += " | "
-                result += " |\n"
-            result += "\n"
-        post_text = """</string>
-        </value>
-      </param> 
-           <param> 
-        <value>
-            <name>sum</name>
-            <string>Updated parameters automagically from code.</string>
-        </value>
-      </param> 
-    </params> 
-    </methodCall>"""
-        return pre_text + escape(result) + post_text
diff --git a/Tools/px4params/output.py b/Tools/px4params/output.py
deleted file mode 100644
index c09246871..000000000
--- a/Tools/px4params/output.py
+++ /dev/null
@@ -1,5 +0,0 @@
-class Output(object):
-    def Save(self, groups, fn):
-        data = self.Generate(groups)
-        with open(fn, 'w') as f:
-            f.write(data)
diff --git a/Tools/px4params/dokuwikiout_listings.py b/Tools/px4params/output_dokuwiki_listings.py
index 33f76b415..83c50ae15 100644
--- a/Tools/px4params/dokuwikiout_listings.py
+++ b/Tools/px4params/output_dokuwiki_listings.py
@@ -1,7 +1,7 @@
-import output
+import codecs
 
-class DokuWikiOutput(output.Output):
-    def Generate(self, groups):
+class DokuWikiListingsOutput():
+    def __init__(self, groups):
         result = ""
         for group in groups:
             result += "==== %s ====\n\n" % group.GetName()
@@ -24,4 +24,8 @@ class DokuWikiOutput(output.Output):
                 if def_val is not None:
                     result += "* Default value: %s\n" % def_val
                 result += "\n"
-        return result
+        self.output = result
+
+    def Save(self, filename):
+        with codecs.open(filename, 'w', 'utf-8') as f:
+            f.write(self.output)
diff --git a/Tools/px4params/output_dokuwiki_tables.py b/Tools/px4params/output_dokuwiki_tables.py
new file mode 100644
index 000000000..aa04304df
--- /dev/null
+++ b/Tools/px4params/output_dokuwiki_tables.py
@@ -0,0 +1,76 @@
+from xml.sax.saxutils import escape
+import codecs
+
+class DokuWikiTablesOutput():
+    def __init__(self, groups):
+        result = "====== Parameter Reference ======\nThis list is auto-generated every few minutes and contains the most recent parameter names and default values.\n\n"
+        for group in groups:
+            result += "==== %s ====\n\n" % group.GetName()
+            result += "|< 100% 20% 20% 10% 10% 10% 30%>|\n"
+            result += "^ Name ^ Description ^  Min ^  Max ^  Default ^ Comment ^\n"
+            for param in group.GetParams():
+                code = param.GetFieldValue("code")
+                name = param.GetFieldValue("short_desc")
+                min_val = param.GetFieldValue("min")
+                max_val = param.GetFieldValue("max")
+                def_val = param.GetFieldValue("default")
+                long_desc = param.GetFieldValue("long_desc")
+
+                name = name.replace("\n", " ")
+                result += "| %s | %s |" % (code, name)
+
+                if min_val is not None:
+                    result += "  %s |" % min_val
+                else:
+                    result += " |"
+
+                if max_val is not None:
+                    result += "  %s |" % max_val
+                else:
+                    result += " |"
+
+                if def_val is not None:
+                    result += "  %s |" % def_val
+                else:
+                    result += " |"
+
+                if long_desc is not None:
+                    long_desc = long_desc.replace("\n", " ")
+                    result += " %s |" % long_desc
+                else:
+                    result += " |"
+
+                result += "\n"
+            result += "\n"
+        self.output = result;
+
+    def Save(self, filename):
+        with codecs.open(filename, 'w', 'utf-8') as f:
+            f.write(self.output)
+
+    def SaveRpc(self, filename):
+        with codecs.open(filename, 'w', 'utf-8') as f:
+            f.write("""<?xml version='1.0'?>
+<methodCall>
+  <methodName>wiki.putPage</methodName>
+      <params>
+          <param> 
+            <value>
+              <string>:firmware:parameters</string>
+            </value>
+          </param>
+          <param> 
+            <value>
+              <string>""")
+            f.write(escape(self.output))
+            f.write("""</string>
+            </value>
+        </param>
+        <param> 
+            <value>
+                <name>sum</name>
+                <string>Updated parameters automagically from code.</string>
+            </value>
+        </param>
+    </params>
+</methodCall>""")
diff --git a/Tools/px4params/xmlout.py b/Tools/px4params/output_xml.py
index d56802b15..e845cd1b1 100644
--- a/Tools/px4params/xmlout.py
+++ b/Tools/px4params/output_xml.py
@@ -1,8 +1,8 @@
-import output
 from xml.dom.minidom import getDOMImplementation
+import codecs
 
-class XMLOutput(output.Output):
-    def Generate(self, groups):
+class XMLOutput():
+    def __init__(self, groups):
         impl = getDOMImplementation()
         xml_document = impl.createDocument(None, "parameters", None)
         xml_parameters = xml_document.documentElement
@@ -19,4 +19,8 @@ class XMLOutput(output.Output):
                     xml_param.appendChild(xml_field)
                     xml_value = xml_document.createTextNode(value)
                     xml_field.appendChild(xml_value)
-        return xml_document.toprettyxml(indent="    ", newl="\n", encoding="utf-8")
+        self.xml_document = xml_document
+
+    def Save(self, filename):
+        with codecs.open(filename, 'w', 'utf-8') as f:
+            self.xml_document.writexml(f, indent="    ", addindent="    ", newl="\n")
diff --git a/Tools/px4params/px_process_params.py b/Tools/px4params/px_process_params.py
index cdf5aba7c..7799f6348 100755
--- a/Tools/px4params/px_process_params.py
+++ b/Tools/px4params/px_process_params.py
@@ -40,22 +40,28 @@
 #
 
 import scanner
-import parser
-import xmlout
-import dokuwikiout
+import srcparser
+import output_xml
+import output_dokuwiki_tables
+import output_dokuwiki_listings
 
 # Initialize parser
-prs = parser.Parser()
+prs = srcparser.Parser()
 
 # Scan directories, and parse the files
 sc = scanner.Scanner()
 sc.ScanDir("../../src", prs)
-output = prs.GetParamGroups()
+groups = prs.GetParamGroups()
 
 # Output into XML
-out = xmlout.XMLOutput()
-out.Save(output, "parameters.xml")
+out = output_xml.XMLOutput(groups)
+out.Save("parameters.xml")
 
-# Output into DokuWiki
-out = dokuwikiout.DokuWikiOutput()
-out.Save(output, "parameters.wiki")
+# Output to DokuWiki listings
+#out = output_dokuwiki_listings.DokuWikiListingsOutput(groups)
+#out.Save("parameters.wiki")
+
+# Output to DokuWiki tables
+out = output_dokuwiki_tables.DokuWikiTablesOutput(groups)
+out.Save("parameters.wiki")
+out.SaveRpc("parameters.wikirpc.xml")
diff --git a/Tools/px4params/scanner.py b/Tools/px4params/scanner.py
index b5a1af47c..8779b7bbf 100644
--- a/Tools/px4params/scanner.py
+++ b/Tools/px4params/scanner.py
@@ -1,5 +1,6 @@
 import os
 import re
+import codecs
 
 class Scanner(object):
     """
@@ -29,6 +30,6 @@ class Scanner(object):
         Scans provided file and passes its contents to the parser using
         parser.Parse method.
         """
-        with open(path, 'r') as f:
+        with codecs.open(path, 'r', 'utf-8') as f:
             contents = f.read()
         parser.Parse(contents)
diff --git a/Tools/px4params/parser.py b/Tools/px4params/srcparser.py
index 251be672f..1b2d30110 100644
--- a/Tools/px4params/parser.py
+++ b/Tools/px4params/srcparser.py
@@ -28,8 +28,7 @@ class ParameterGroup(object):
         state of the parser.
         """
         return sorted(self.params,
-                cmp=lambda x, y: cmp(x.GetFieldValue("code"),
-                    y.GetFieldValue("code")))
+                key=lambda x: x.GetFieldValue("code"))
 
 class Parameter(object):
     """
@@ -61,9 +60,10 @@ class Parameter(object):
         """
         Return list of existing field codes in convenient order
         """
-        return sorted(self.fields.keys(),
-                cmp=lambda x, y: cmp(self.priority.get(y, 0),
-                    self.priority.get(x, 0)) or cmp(x, y))
+        keys = self.fields.keys()
+        keys = sorted(keys)
+        keys = sorted(keys, key=lambda x: self.priority.get(x, 0), reverse=True)
+        return keys
 
     def GetFieldValue(self, code):
         """
@@ -197,7 +197,7 @@ class Parser(object):
                             if tag == "group":
                                 group = tags[tag]
                             elif tag not in self.valid_tags:
-                                sys.stderr.write("Skipping invalid"
+                                sys.stderr.write("Skipping invalid "
                                         "documentation tag: '%s'\n" % tag)
                             else:
                                 param.SetField(tag, tags[tag])
@@ -214,7 +214,7 @@ class Parser(object):
         object. Note that returned object is not a copy. Modifications affect
         state of the parser.
         """
-        return sorted(self.param_groups.values(),
-                cmp=lambda x, y: cmp(self.priority.get(y.GetName(), 0),
-                    self.priority.get(x.GetName(), 0)) or cmp(x.GetName(),
-                        y.GetName()))
+        groups = self.param_groups.values()
+        groups = sorted(groups, key=lambda x: x.GetName())
+        groups = sorted(groups, key=lambda x: self.priority.get(x.GetName(), 0), reverse=True)
+        return groups
diff --git a/Tools/px4params/xmlrpc.sh b/Tools/px4params/xmlrpc.sh
index 36c52ff71..efd177f46 100644
--- a/Tools/px4params/xmlrpc.sh
+++ b/Tools/px4params/xmlrpc.sh
@@ -2,4 +2,4 @@ python px_process_params.py
 
 rm cookies.txt
 curl --cookie cookies.txt --cookie-jar cookies.txt --user-agent Mozilla/4.0 --data "u=$XMLRPCUSER&p=$XMLRPCPASS" https://pixhawk.org/start?do=login
-curl -k --cookie cookies.txt -H "Content-Type: application/xml" -X POST --data-binary @parameters.wiki "https://pixhawk.org/lib/exe/xmlrpc.php"
+curl -k --cookie cookies.txt -H "Content-Type: application/xml" -X POST --data-binary @parameters.wikirpc.xml "https://pixhawk.org/lib/exe/xmlrpc.php"
diff --git a/src/lib/launchdetection/launchdetection_params.c b/src/lib/launchdetection/launchdetection_params.c
index 63a8981aa..45d7957f1 100644
--- a/src/lib/launchdetection/launchdetection_params.c
+++ b/src/lib/launchdetection/launchdetection_params.c
@@ -45,28 +45,46 @@
 #include <systemlib/param/param.h>
 
 /*
- * Launch detection parameters, accessible via MAVLink
+ * Catapult launch detection parameters, accessible via MAVLink
  *
  */
 
-/* Catapult Launch detection */
-
-// @DisplayName		Switch to enable launchdetection
-// @Description		if set to 1 launchdetection is enabled
-// @Range		0 or 1
+/**
+ * Enable launch detection.
+ *
+ * @min 0
+ * @max 1
+ * @group Launch detection
+ */
 PARAM_DEFINE_INT32(LAUN_ALL_ON, 0);
 
-// @DisplayName		Catapult Accelerometer Threshold
-// @Description		LAUN_CAT_A * LAUN_CAT_T serves as threshold to trigger launch detection
-// @Range		> 0
+/**
+ * Catapult accelerometer theshold.
+ *
+ * LAUN_CAT_A * LAUN_CAT_T serves as threshold to trigger launch detection.
+ *
+ * @min 0
+ * @group Launch detection
+ */
 PARAM_DEFINE_FLOAT(LAUN_CAT_A, 30.0f);
 
-// @DisplayName		Catapult Time Threshold
-// @Description		LAUN_CAT_A * LAUN_CAT_T serves as threshold to trigger launch detection
-// @Range		> 0, in seconds
+/**
+ * Catapult time theshold.
+ *
+ * LAUN_CAT_A * LAUN_CAT_T serves as threshold to trigger launch detection.
+ *
+ * @min 0
+ * @group Launch detection
+ */
 PARAM_DEFINE_FLOAT(LAUN_CAT_T, 0.05f);
 
-// @DisplayName		Throttle setting while detecting the launch
-// @Description		The throttle is set to this value while the system is waiting for the takeoff
-// @Range		0 to 1
+/**
+ * Throttle setting while detecting launch.
+ *
+ * The throttle is set to this value while the system is waiting for the take-off.
+ *
+ * @min 0
+ * @max 1
+ * @group Launch detection
+ */
 PARAM_DEFINE_FLOAT(LAUN_THR_PRE, 0.0f);
diff --git a/src/modules/commander/commander_params.c b/src/modules/commander/commander_params.c
index d3155f7bf..80ca68f21 100644
--- a/src/modules/commander/commander_params.c
+++ b/src/modules/commander/commander_params.c
@@ -48,7 +48,39 @@
 PARAM_DEFINE_FLOAT(TRIM_ROLL, 0.0f);
 PARAM_DEFINE_FLOAT(TRIM_PITCH, 0.0f);
 PARAM_DEFINE_FLOAT(TRIM_YAW, 0.0f);
+
+/**
+ * Empty cell voltage.
+ *
+ * Defines the voltage where a single cell of the battery is considered empty.
+ *
+ * @group Battery Calibration
+ */
 PARAM_DEFINE_FLOAT(BAT_V_EMPTY, 3.4f);
+
+/**
+ * Full cell voltage.
+ *
+ * Defines the voltage where a single cell of the battery is considered full.
+ *
+ * @group Battery Calibration
+ */
 PARAM_DEFINE_FLOAT(BAT_V_FULL, 3.9f);
+
+/**
+ * Number of cells.
+ *
+ * Defines the number of cells the attached battery consists of.
+ *
+ * @group Battery Calibration
+ */
 PARAM_DEFINE_INT32(BAT_N_CELLS, 3);
+
+/**
+ * Battery capacity.
+ *
+ * Defines the capacity of the attached battery.
+ *
+ * @group Battery Calibration
+ */
 PARAM_DEFINE_FLOAT(BAT_CAPACITY, -1.0f);
diff --git a/src/modules/fw_pos_control_l1/fw_pos_control_l1_params.c b/src/modules/fw_pos_control_l1/fw_pos_control_l1_params.c
index 512ca7b8a..62a340e90 100644
--- a/src/modules/fw_pos_control_l1/fw_pos_control_l1_params.c
+++ b/src/modules/fw_pos_control_l1/fw_pos_control_l1_params.c
@@ -40,12 +40,10 @@
  */
 
 #include <nuttx/config.h>
-
 #include <systemlib/param/param.h>
 
 /*
  * Controller parameters, accessible via MAVLink
- *
  */
 
 /**
@@ -119,58 +117,268 @@ PARAM_DEFINE_FLOAT(FW_P_LIM_MIN, -45.0f);
  */
 PARAM_DEFINE_FLOAT(FW_P_LIM_MAX, 45.0f);
 
-
+/**
+ * Controller roll limit
+ *
+ * The maximum roll the controller will output.
+ *
+ * @unit degrees
+ * @min 0.0
+ * @group L1 Control
+ */
 PARAM_DEFINE_FLOAT(FW_R_LIM, 45.0f);
 
+/**
+ * Throttle limit max
+ *
+ * This is the maximum throttle % that can be used by the controller. 
+ * For overpowered aircraft, this should be reduced to a value that 
+ * provides sufficient thrust to climb at the maximum pitch angle PTCH_MAX.
+ *
+ * @group L1 Control
+ */
+PARAM_DEFINE_FLOAT(FW_THR_MAX, 1.0f);
 
+/**
+ * Throttle limit min
+ *
+ * This is the minimum throttle % that can be used by the controller. 
+ * For electric aircraft this will normally be set to zero, but can be set 
+ * to a small non-zero value if a folding prop is fitted to prevent the 
+ * prop from folding and unfolding repeatedly in-flight or to provide 
+ * some aerodynamic drag from a turning prop to improve the descent rate.
+ *
+ * For aircraft with internal combustion engine this parameter should be set
+ * for desired idle rpm.
+ *
+ * @group L1 Control
+ */
 PARAM_DEFINE_FLOAT(FW_THR_MIN, 0.0f);
 
-
-PARAM_DEFINE_FLOAT(FW_THR_MAX, 1.0f);
-
+/**
+ * Throttle limit value before flare
+ *
+ * This throttle value will be set as throttle limit at FW_LND_TLALT, 
+ * before arcraft will flare.
+ *
+ * @group L1 Control
+ */
 PARAM_DEFINE_FLOAT(FW_THR_LND_MAX, 1.0f);
 
+/**
+ * Maximum climb rate
+ *
+ * This is the best climb rate that the aircraft can achieve with 
+ * the throttle set to THR_MAX and the airspeed set to the 
+ * default value. For electric aircraft make sure this number can be 
+ * achieved towards the end of flight when the battery voltage has reduced. 
+ * The setting of this parameter can be checked by commanding a positive 
+ * altitude change of 100m in loiter, RTL or guided mode. If the throttle 
+ * required to climb is close to THR_MAX and the aircraft is maintaining 
+ * airspeed, then this parameter is set correctly. If the airspeed starts 
+ * to reduce, then the parameter is set to high, and if the throttle 
+ * demand required to climb and maintain speed is noticeably less than 
+ * FW_THR_MAX, then either FW_T_CLMB_MAX should be increased or 
+ * FW_THR_MAX reduced.
+ *
+ * @group L1 Control
+ */
 PARAM_DEFINE_FLOAT(FW_T_CLMB_MAX, 5.0f);
 
-
+/**
+ * Minimum descent rate
+ *
+ * This is the sink rate of the aircraft with the throttle 
+ * set to THR_MIN and flown at the same airspeed as used 
+ * to measure FW_T_CLMB_MAX.
+ *
+ * @group L1 Control
+ */
 PARAM_DEFINE_FLOAT(FW_T_SINK_MIN, 2.0f);
 
+/**
+ * Maximum descent rate
+ *
+ * This sets the maximum descent rate that the controller will use. 
+ * If this value is too large, the aircraft can over-speed on descent. 
+ * This should be set to a value that can be achieved without 
+ * exceeding the lower pitch angle limit and without over-speeding 
+ * the aircraft.
+ *
+ * @group L1 Control
+ */
+PARAM_DEFINE_FLOAT(FW_T_SINK_MAX, 5.0f);
 
+/**
+ * TECS time constant
+ *
+ * This is the time constant of the TECS control algorithm (in seconds). 
+ * Smaller values make it faster to respond, larger values make it slower
+ * to respond.
+ *
+ * @group L1 Control
+ */
 PARAM_DEFINE_FLOAT(FW_T_TIME_CONST, 5.0f);
 
-
+/**
+ * Throttle damping factor
+ *
+ * This is the damping gain for the throttle demand loop. 
+ * Increase to add damping to correct for oscillations in speed and height.
+ *
+ * @group L1 Control
+ */
 PARAM_DEFINE_FLOAT(FW_T_THR_DAMP, 0.5f);
 
-
+/**
+ * Integrator gain
+ *
+ * This is the integrator gain on the control loop. 
+ * Increasing this gain increases the speed at which speed 
+ * and height offsets are trimmed out, but reduces damping and 
+ * increases overshoot.
+ *
+ * @group L1 Control
+ */
 PARAM_DEFINE_FLOAT(FW_T_INTEG_GAIN, 0.1f);
 
-
+/**
+ * Maximum vertical acceleration
+ *
+ * This is the maximum vertical acceleration (in metres/second^2) 
+ * either up or down that the controller will use to correct speed 
+ * or height errors. The default value of 7 m/s/s (equivalent to +- 0.7 g) 
+ * allows for reasonably aggressive pitch changes if required to recover 
+ * from under-speed conditions.
+ *
+ * @group L1 Control
+ */
 PARAM_DEFINE_FLOAT(FW_T_VERT_ACC, 7.0f);
 
-
+/**
+ * Complementary filter "omega" parameter for height
+ *
+ * This is the cross-over frequency (in radians/second) of the complementary 
+ * filter used to fuse vertical acceleration and barometric height to obtain 
+ * an estimate of height rate and height. Increasing this frequency weights 
+ * the solution more towards use of the barometer, whilst reducing it weights 
+ * the solution more towards use of the accelerometer data.
+ *
+ * @group L1 Control
+ */
 PARAM_DEFINE_FLOAT(FW_T_HGT_OMEGA, 3.0f);
 
-
+/**
+ * Complementary filter "omega" parameter for speed
+ *
+ * This is the cross-over frequency (in radians/second) of the complementary 
+ * filter used to fuse longitudinal acceleration and airspeed to obtain an 
+ * improved airspeed estimate. Increasing this frequency weights the solution
+ * more towards use of the arispeed sensor, whilst reducing it weights the 
+ * solution more towards use of the accelerometer data.
+ *
+ * @group L1 Control
+ */
 PARAM_DEFINE_FLOAT(FW_T_SPD_OMEGA, 2.0f);
 
-
+/**
+ * Roll -> Throttle feedforward
+ *
+ * Increasing this gain turn increases the amount of throttle that will 
+ * be used to compensate for the additional drag created by turning. 
+ * Ideally this should be set to  approximately 10 x the extra sink rate 
+ * in m/s created by a 45 degree bank turn. Increase this gain if 
+ * the aircraft initially loses energy in turns and reduce if the 
+ * aircraft initially gains energy in turns. Efficient high aspect-ratio 
+ * aircraft (eg powered sailplanes) can use a lower value, whereas 
+ * inefficient low aspect-ratio models (eg delta wings) can use a higher value.
+ *
+ * @group L1 Control
+ */
 PARAM_DEFINE_FLOAT(FW_T_RLL2THR, 10.0f);
 
-
+/**
+ * Speed <--> Altitude priority
+ *
+ * This parameter adjusts the amount of weighting that the pitch control 
+ * applies to speed vs height errors. 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. 
+ * Setting it to 2.0 will cause the pitch control loop to control speed 
+ * and ignore height errors. This will normally reduce airspeed errors, 
+ * but give larger height errors. The default value of 1.0 allows the pitch 
+ * control to simultaneously control height and speed. 
+ * Note to Glider Pilots - set this parameter to 2.0 (The glider will 
+ * adjust its pitch angle to maintain airspeed, ignoring changes in height).
+ *
+ * @group L1 Control
+ */
 PARAM_DEFINE_FLOAT(FW_T_SPDWEIGHT, 1.0f);
 
-
+/**
+ * Pitch damping factor
+ *
+ * This is the damping gain for the pitch demand loop. Increase to add 
+ * damping to correct for oscillations in height. The default value of 0.0 
+ * will work well provided the pitch to servo controller has been tuned 
+ * properly.
+ *
+ * @group L1 Control
+ */
 PARAM_DEFINE_FLOAT(FW_T_PTCH_DAMP, 0.0f);
 
-
-PARAM_DEFINE_FLOAT(FW_T_SINK_MAX, 5.0f);
-
+/**
+ * Height rate P factor
+ *
+ * @group L1 Control
+ */
 PARAM_DEFINE_FLOAT(FW_T_HRATE_P, 0.05f);
+
+/**
+ * Speed rate P factor
+ *
+ * @group L1 Control
+ */
 PARAM_DEFINE_FLOAT(FW_T_SRATE_P, 0.05f);
 
+/**
+ * Landing slope angle
+ *
+ * @group L1 Control
+ */
 PARAM_DEFINE_FLOAT(FW_LND_ANG, 5.0f);
+
+/**
+ * Landing slope length
+ *
+ * @group L1 Control
+ */
 PARAM_DEFINE_FLOAT(FW_LND_SLLR, 0.9f);
+
+/**
+ *
+ *
+ * @group L1 Control
+ */
 PARAM_DEFINE_FLOAT(FW_LND_HVIRT, 10.0f);
+
+/**
+ * Landing flare altitude (relative)
+ *
+ * @group L1 Control
+ */
 PARAM_DEFINE_FLOAT(FW_LND_FLALT, 15.0f);
+
+/**
+ * Landing throttle limit altitude (relative)
+ *
+ * @group L1 Control
+ */
 PARAM_DEFINE_FLOAT(FW_LND_TLALT, 5.0f);
+
+/**
+ * Landing heading hold horizontal distance
+ *
+ * @group L1 Control
+ */
 PARAM_DEFINE_FLOAT(FW_LND_HHDIST, 15.0f);
diff --git a/src/modules/mavlink/mavlink.c b/src/modules/mavlink/mavlink.c
index 4d975066f..ade4469c5 100644
--- a/src/modules/mavlink/mavlink.c
+++ b/src/modules/mavlink/mavlink.c
@@ -76,8 +76,20 @@
 #include <uORB/topics/mission_result.h>
 
 /* define MAVLink specific parameters */
+/**
+ * MAVLink system ID
+ * @group MAVLink
+ */
 PARAM_DEFINE_INT32(MAV_SYS_ID, 1);
+/**
+ * MAVLink component ID
+ * @group MAVLink
+ */
 PARAM_DEFINE_INT32(MAV_COMP_ID, 50);
+/**
+ * MAVLink type
+ * @group MAVLink
+ */
 PARAM_DEFINE_INT32(MAV_TYPE, MAV_TYPE_FIXED_WING);
 
 __EXPORT int mavlink_main(int argc, char *argv[]);
diff --git a/src/modules/navigator/geofence_params.c b/src/modules/navigator/geofence_params.c
index 20dd1fe2f..5831a0ca9 100644
--- a/src/modules/navigator/geofence_params.c
+++ b/src/modules/navigator/geofence_params.c
@@ -45,11 +45,17 @@
 #include <systemlib/param/param.h>
 
 /*
- * geofence parameters, accessible via MAVLink
- *
+ * Geofence parameters, accessible via MAVLink
  */
 
-// @DisplayName		Switch to enable geofence
-// @Description		if set to 1 geofence is enabled, defaults to 1 because geofence is only enabled when the geofence.txt file is present
-// @Range		0 or 1
+/**
+ * Enable geofence.
+ *
+ * Set to 1 to enable geofence.
+ * Defaults to 1 because geofence is only enabled when the geofence.txt file is present.
+ *
+ * @min 0
+ * @max 1
+ * @group Geofence
+ */
 PARAM_DEFINE_INT32(GF_ON, 1);
diff --git a/src/modules/navigator/navigator_params.c b/src/modules/navigator/navigator_params.c
index 9e05bbffa..ec7a4e229 100644
--- a/src/modules/navigator/navigator_params.c
+++ b/src/modules/navigator/navigator_params.c
@@ -50,15 +50,72 @@
 
 /*
  * Navigator parameters, accessible via MAVLink
- *
  */
 
+/**
+ * Minimum altitude
+ *
+ * @group Navigation
+ */
 PARAM_DEFINE_FLOAT(NAV_MIN_ALT, 50.0f);
+
+/**
+ * Waypoint acceptance radius.
+ *
+ * @group Navigation
+ */
 PARAM_DEFINE_FLOAT(NAV_ACCEPT_RAD, 10.0f);
+
+/**
+ * Loiter radius.
+ *
+ * @group Navigation
+ */
 PARAM_DEFINE_FLOAT(NAV_LOITER_RAD, 50.0f);
+
+/**
+ * @group Navigation
+ */
 PARAM_DEFINE_INT32(NAV_ONB_MIS_EN, 0);
+
+/**
+ * Default take-off altitude.
+ *
+ * @group Navigation
+ */
 PARAM_DEFINE_FLOAT(NAV_TAKEOFF_ALT, 10.0f);	// default TAKEOFF altitude
+
+/**
+ * Landing altitude.
+ *
+ * Slowly descend from this altitude when landing.
+ *
+ * @group Navigation
+ */
 PARAM_DEFINE_FLOAT(NAV_LAND_ALT, 5.0f);		// slow descend from this altitude when landing
+
+/**
+ * Return-to-land altitude.
+ *
+ * Minimum altitude for going home in RTL mode.
+ *
+ * @group Navigation
+ */
 PARAM_DEFINE_FLOAT(NAV_RTL_ALT, 30.0f);		// min altitude for going home in RTL mode
-PARAM_DEFINE_FLOAT(NAV_RTL_LAND_T, -1.0f);	// delay after descend before landing, if set to -1 the system will not land but loiter at NAV_LAND_ALT
-PARAM_DEFINE_INT32(NAV_PARACHUTE_EN, 0);	// enable parachute deployment
+
+/**
+ * Return-to-land delay.
+ *
+ * Delay after descend before landing.
+ * If set to -1 the system will not land but loiter at NAV_LAND_ALT.
+ *
+ * @group Navigation
+ */
+PARAM_DEFINE_FLOAT(NAV_RTL_LAND_T, -1.0f);
+
+/**
+ * Enable parachute deployment.
+ *
+ * @group Navigation
+ */
+PARAM_DEFINE_INT32(NAV_PARACHUTE_EN, 0);
diff --git a/src/modules/sensors/sensor_params.c b/src/modules/sensors/sensor_params.c
index 30659fd3a..288c6e00a 100644
--- a/src/modules/sensors/sensor_params.c
+++ b/src/modules/sensors/sensor_params.c
@@ -42,13 +42,10 @@
  */
 
 #include <nuttx/config.h>
-
 #include <systemlib/param/param.h>
 
 /**
- * Gyro X offset
- *
- * This is an X-axis offset for the gyro. Adjust it according to the calibration data.
+ * Gyro X-axis offset
  *
  * @min -10.0
  * @max 10.0
@@ -57,7 +54,7 @@
 PARAM_DEFINE_FLOAT(SENS_GYRO_XOFF, 0.0f);
 
 /**
- * Gyro Y offset
+ * Gyro Y-axis offset
  *
  * @min -10.0
  * @max 10.0
@@ -66,7 +63,7 @@ PARAM_DEFINE_FLOAT(SENS_GYRO_XOFF, 0.0f);
 PARAM_DEFINE_FLOAT(SENS_GYRO_YOFF, 0.0f);
 
 /**
- * Gyro Z offset
+ * Gyro Z-axis offset
  *
  * @min -5.0
  * @max 5.0
@@ -75,9 +72,7 @@ PARAM_DEFINE_FLOAT(SENS_GYRO_YOFF, 0.0f);
 PARAM_DEFINE_FLOAT(SENS_GYRO_ZOFF, 0.0f);
 
 /**
- * Gyro X scaling
- *
- * X-axis scaling.
+ * Gyro X-axis scaling factor
  *
  * @min -1.5
  * @max 1.5
@@ -86,9 +81,7 @@ PARAM_DEFINE_FLOAT(SENS_GYRO_ZOFF, 0.0f);
 PARAM_DEFINE_FLOAT(SENS_GYRO_XSCALE, 1.0f);
 
 /**
- * Gyro Y scaling
- *
- * Y-axis scaling.
+ * Gyro Y-axis scaling factor
  *
  * @min -1.5
  * @max 1.5
@@ -97,9 +90,7 @@ PARAM_DEFINE_FLOAT(SENS_GYRO_XSCALE, 1.0f);
 PARAM_DEFINE_FLOAT(SENS_GYRO_YSCALE, 1.0f);
 
 /**
- * Gyro Z scaling
- *
- * Z-axis scaling.
+ * Gyro Z-axis scaling factor
  *
  * @min -1.5
  * @max 1.5
@@ -107,10 +98,9 @@ PARAM_DEFINE_FLOAT(SENS_GYRO_YSCALE, 1.0f);
  */
 PARAM_DEFINE_FLOAT(SENS_GYRO_ZSCALE, 1.0f);
 
+
 /**
- * Magnetometer X offset
- *
- * This is an X-axis offset for the magnetometer.
+ * Magnetometer X-axis offset
  *
  * @min -500.0
  * @max 500.0
@@ -119,9 +109,7 @@ PARAM_DEFINE_FLOAT(SENS_GYRO_ZSCALE, 1.0f);
 PARAM_DEFINE_FLOAT(SENS_MAG_XOFF, 0.0f);
 
 /**
- * Magnetometer Y offset
- *
- * This is an Y-axis offset for the magnetometer.
+ * Magnetometer Y-axis offset
  *
  * @min -500.0
  * @max 500.0
@@ -130,9 +118,7 @@ PARAM_DEFINE_FLOAT(SENS_MAG_XOFF, 0.0f);
 PARAM_DEFINE_FLOAT(SENS_MAG_YOFF, 0.0f);
 
 /**
- * Magnetometer Z offset
- *
- * This is an Z-axis offset for the magnetometer.
+ * Magnetometer Z-axis offset
  *
  * @min -500.0
  * @max 500.0
@@ -140,24 +126,134 @@ PARAM_DEFINE_FLOAT(SENS_MAG_YOFF, 0.0f);
  */
 PARAM_DEFINE_FLOAT(SENS_MAG_ZOFF, 0.0f);
 
+/**
+ * Magnetometer X-axis scaling factor
+ *
+ * @group Sensor Calibration
+ */
 PARAM_DEFINE_FLOAT(SENS_MAG_XSCALE, 1.0f);
+
+/**
+ * Magnetometer Y-axis scaling factor
+ *
+ * @group Sensor Calibration
+ */
 PARAM_DEFINE_FLOAT(SENS_MAG_YSCALE, 1.0f);
+
+/**
+ * Magnetometer Z-axis scaling factor
+ *
+ * @group Sensor Calibration
+ */
 PARAM_DEFINE_FLOAT(SENS_MAG_ZSCALE, 1.0f);
 
+
+/**
+ * Accelerometer X-axis offset
+ *
+ * @group Sensor Calibration
+ */
 PARAM_DEFINE_FLOAT(SENS_ACC_XOFF, 0.0f);
+
+/**
+ * Accelerometer Y-axis offset
+ *
+ * @group Sensor Calibration
+ */
 PARAM_DEFINE_FLOAT(SENS_ACC_YOFF, 0.0f);
+
+/**
+ * Accelerometer Z-axis offset
+ *
+ * @group Sensor Calibration
+ */
 PARAM_DEFINE_FLOAT(SENS_ACC_ZOFF, 0.0f);
 
+/**
+ * Accelerometer X-axis scaling factor
+ *
+ * @group Sensor Calibration
+ */
 PARAM_DEFINE_FLOAT(SENS_ACC_XSCALE, 1.0f);
+
+/**
+ * Accelerometer Y-axis scaling factor
+ *
+ * @group Sensor Calibration
+ */
 PARAM_DEFINE_FLOAT(SENS_ACC_YSCALE, 1.0f);
+
+/**
+ * Accelerometer Z-axis scaling factor
+ *
+ * @group Sensor Calibration
+ */
 PARAM_DEFINE_FLOAT(SENS_ACC_ZSCALE, 1.0f);
 
+
+/**
+ * Differential pressure sensor offset
+ *
+ * @group Sensor Calibration
+ */
 PARAM_DEFINE_FLOAT(SENS_DPRES_OFF, 0.0f);
+
+/**
+ * Differential pressure sensor analog enabled
+ *
+ * @group Sensor Calibration
+ */
 PARAM_DEFINE_INT32(SENS_DPRES_ANA, 0);
 
+
+/**
+ * Board rotation
+ *
+ * This parameter defines the rotation of the FMU board relative to the platform.
+ * Possible values are:
+ *    0 = No rotation
+ *    1 = Yaw 45°
+ *    2 = Yaw 90°
+ *    3 = Yaw 135°
+ *    4 = Yaw 180°
+ *    5 = Yaw 225°
+ *    6 = Yaw 270°
+ *    7 = Yaw 315°
+ *    8 = Roll 180°
+ *    9 = Roll 180°, Yaw 45°
+ *   10 = Roll 180°, Yaw 90°
+ *   11 = Roll 180°, Yaw 135°
+ *   12 = Pitch 180°
+ *   13 = Roll 180°, Yaw 225°
+ *   14 = Roll 180°, Yaw 270°
+ *   15 = Roll 180°, Yaw 315°
+ *   16 = Roll 90°
+ *   17 = Roll 90°, Yaw 45°
+ *   18 = Roll 90°, Yaw 90°
+ *   19 = Roll 90°, Yaw 135°
+ *   20 = Roll 270°
+ *   21 = Roll 270°, Yaw 45°
+ *   22 = Roll 270°, Yaw 90°
+ *   23 = Roll 270°, Yaw 135°
+ *   24 = Pitch 90°
+ *   25 = Pitch 270°
+ *
+ * @group Sensor Calibration
+ */
 PARAM_DEFINE_INT32(SENS_BOARD_ROT, 0);
+
+/**
+ * External magnetometer rotation
+ *
+ * This parameter defines the rotation of the external magnetometer relative
+ * to the platform (not relative to the FMU).
+ * See SENS_BOARD_ROT for possible values.
+ *
+ * @group Sensor Calibration
+ */
 PARAM_DEFINE_INT32(SENS_EXT_MAG_ROT, 0);
 
+
 /**
  * RC Channel 1 Minimum
  *
@@ -367,20 +463,52 @@ PARAM_DEFINE_FLOAT(RC18_DZ, 0.0f);
 #ifdef CONFIG_ARCH_BOARD_PX4FMU_V1
 PARAM_DEFINE_INT32(RC_RL1_DSM_VCC, 0); /* Relay 1 controls DSM VCC */
 #endif
-PARAM_DEFINE_INT32(RC_DSM_BIND, -1); /* -1 = Idle, 0 = Start DSM2 bind, 1 = Start DSMX bind */
 
+/**
+ * DSM binding trigger.
+ *
+ * -1 = Idle, 0 = Start DSM2 bind, 1 = Start DSMX bind
+ *
+ * @group Radio Calibration
+ */
+PARAM_DEFINE_INT32(RC_DSM_BIND, -1);
+
+
+/**
+ * Scaling factor for battery voltage sensor on PX4IO.
+ *
+ * @group Battery Calibration
+ */
 PARAM_DEFINE_INT32(BAT_V_SCALE_IO, 10000);
+
 #ifdef CONFIG_ARCH_BOARD_PX4FMU_V2
+/**
+ * Scaling factor for battery voltage sensor on FMU v2.
+ *
+ * @group Battery Calibration
+ */
 PARAM_DEFINE_FLOAT(BAT_V_SCALING, 0.0082f);
 #else
-/* default is conversion factor for the PX4IO / PX4IOAR board, the factor for PX4FMU standalone is different */
-/* PX4IOAR: 0.00838095238 */
-/* FMU standalone: 1/(10 / (47+10)) * (3.3 / 4095) = 0.00459340659 */
-/* FMU with PX4IOAR: (3.3f * 52.0f / 5.0f / 4095.0f) */
+/**
+ * Scaling factor for battery voltage sensor on FMU v1.
+ *
+ * FMUv1 standalone: 1/(10 / (47+10)) * (3.3 / 4095) = 0.00459340659
+ * FMUv1 with PX4IO: 0.00459340659
+ * FMUv1 with PX4IOAR: (3.3f * 52.0f / 5.0f / 4095.0f) = 0.00838095238
+ *
+ * @group Battery Calibration
+ */
 PARAM_DEFINE_FLOAT(BAT_V_SCALING, 0.00459340659f);
 #endif
+
+/**
+ * Scaling factor for battery current sensor.
+ *
+ * @group Battery Calibration
+ */
 PARAM_DEFINE_FLOAT(BAT_C_SCALING, 0.0124);	/* scaling for 3DR power brick */
 
+
 /**
  * Roll control channel mapping.
  *
@@ -446,22 +574,127 @@ PARAM_DEFINE_INT32(RC_MAP_YAW, 4);
  * @group Radio Calibration
  */
 PARAM_DEFINE_INT32(RC_MAP_MODE_SW, 0);
+
+/**
+ * Return switch channel mapping.
+ *
+ * @min 0
+ * @max 18
+ * @group Radio Calibration
+ */
 PARAM_DEFINE_INT32(RC_MAP_RETURN_SW, 0);
+
+/**
+ * Assist switch channel mapping.
+ *
+ * @min 0
+ * @max 18
+ * @group Radio Calibration
+ */
 PARAM_DEFINE_INT32(RC_MAP_ASSIST_SW, 0);
+
+/**
+ * Mission switch channel mapping.
+ *
+ * @min 0
+ * @max 18
+ * @group Radio Calibration
+ */
 PARAM_DEFINE_INT32(RC_MAP_MISSIO_SW, 0);
 
 //PARAM_DEFINE_INT32(RC_MAP_OFFB_SW, 0);
 
+/**
+ * Flaps channel mapping.
+ *
+ * @min 0
+ * @max 18
+ * @group Radio Calibration
+ */
 PARAM_DEFINE_INT32(RC_MAP_FLAPS, 0);
 
-PARAM_DEFINE_INT32(RC_MAP_AUX1, 0);	/**< default function: camera pitch */
+/**
+ * Auxiliary switch 1 channel mapping.
+ *
+ * Default function: Camera pitch
+ *
+ * @min 0
+ * @max 18
+ * @group Radio Calibration
+ */
+PARAM_DEFINE_INT32(RC_MAP_AUX1, 0);
+
+/**
+ * Auxiliary switch 2 channel mapping.
+ *
+ * Default function: Camera roll
+ *
+ * @min 0
+ * @max 18
+ * @group Radio Calibration
+ */
 PARAM_DEFINE_INT32(RC_MAP_AUX2, 0);	/**< default function: camera roll */
-PARAM_DEFINE_INT32(RC_MAP_AUX3, 0);	/**< default function: camera azimuth / yaw */
 
+/**
+ * Auxiliary switch 3 channel mapping.
+ *
+ * Default function: Camera azimuth / yaw
+ *
+ * @min 0
+ * @max 18
+ * @group Radio Calibration
+ */
+PARAM_DEFINE_INT32(RC_MAP_AUX3, 0);
+
+
+/**
+ * Roll scaling factor
+ *
+ * @group Radio Calibration
+ */
 PARAM_DEFINE_FLOAT(RC_SCALE_ROLL, 0.6f);
+
+/**
+ * Pitch scaling factor
+ *
+ * @group Radio Calibration
+ */
 PARAM_DEFINE_FLOAT(RC_SCALE_PITCH, 0.6f);
+
+/**
+ * Yaw scaling factor
+ *
+ * @group Radio Calibration
+ */
 PARAM_DEFINE_FLOAT(RC_SCALE_YAW, 2.0f);
 
-PARAM_DEFINE_INT32(RC_FS_CH, 0);	/**< RC failsafe channel, 0 = disable */
-PARAM_DEFINE_INT32(RC_FS_MODE, 0);	/**< RC failsafe mode: 0 = too low means signal loss, 1 = too high means signal loss */
-PARAM_DEFINE_FLOAT(RC_FS_THR, 800);	/**< RC failsafe PWM threshold */
+
+/**
+ * Failsafe channel mapping.
+ *
+ * @min 0
+ * @max 18
+ * @group Radio Calibration
+ */
+PARAM_DEFINE_INT32(RC_FS_CH, 0);
+
+/**
+ * Failsafe channel mode.
+ *
+ * 0 = too low means signal loss,
+ * 1 = too high means signal loss
+ *
+ * @min 0
+ * @max 1
+ * @group Radio Calibration
+ */
+PARAM_DEFINE_INT32(RC_FS_MODE, 0);
+
+/**
+ * Failsafe channel PWM threshold.
+ *
+ * @min 0
+ * @max 1
+ * @group Radio Calibration
+ */
+PARAM_DEFINE_FLOAT(RC_FS_THR, 800);
diff --git a/src/modules/systemlib/system_params.c b/src/modules/systemlib/system_params.c
index 75be090f8..cb35a2541 100644
--- a/src/modules/systemlib/system_params.c
+++ b/src/modules/systemlib/system_params.c
@@ -40,8 +40,23 @@
 #include <nuttx/config.h>
 #include <systemlib/param/param.h>
 
-// Auto-start script with index #n
+/**
+ * Auto-start script index.
+ *
+ * Defines the auto-start script used to bootstrap the system.
+ *
+ * @group System
+ */
 PARAM_DEFINE_INT32(SYS_AUTOSTART, 0);
 
-// Automatically configure default values
+/**
+ * Automatically configure default values.
+ *
+ * Set to 1 to set platform-specific parameters to their default
+ * values on next system startup. 
+ *
+ * @min 0
+ * @max 1
+ * @group System
+ */
 PARAM_DEFINE_INT32(SYS_AUTOCONFIG, 0);