Add unit to AGL property name, comment for AGL member, prevent negati…

…ve AGL value
seanmcleod · Jun 30, 2024 · 1f73cf7 · 1f73cf7
1 parent 242650d
commit 1f73cf7
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Showing 2 changed files with 7 additions and 5 deletions.
diff --git a/src/models/FGLGear.cpp b/src/models/FGLGear.cpp
@@ -293,11 +293,13 @@ const FGColumnVector3& FGLGear::GetBodyForces(void)
   gearLoc = in.Location.LocalToLocation(vLocalGear);
 
   // Compute the height of the theoretical location of the wheel (if strut is
-  // not compressed) with respect to the ground level
+  // not compressed) with respect to the ground level (AGL)
   double height = fdmex->GetInertial()->GetContactPoint(gearLoc, contact,
     normal, terrainVel, dummy);
 
-  AGL = height;
+  // Don't want strut compression when in contact with the ground to return 
+  // a negative AGL
+  AGL = max(height, 0.0);
 
   if (isRetractable) gearPos = GetGearUnitPos();
 
@@ -788,7 +790,7 @@ void FGLGear::bind(FGPropertyManager* PropertyManager)
     return;
   }
 
-  property_name = base_property_name + "/AGL";
+  property_name = base_property_name + "/AGL-ft";
   PropertyManager->Tie(property_name.c_str(), &AGL);
   property_name = base_property_name + "/WOW";
   PropertyManager->Tie( property_name.c_str(), &WOW );

diff --git a/src/models/FGLGear.h b/src/models/FGLGear.h
@@ -355,7 +355,7 @@ class JSBSIM_API FGLGear : public FGForce
   double maximumForce = DBL_MAX;
   double bumpiness = 0.0;
   bool isSolid = true;
-  bool WOW;
+  bool WOW; // Weight On Wheel
   bool lastWOW;
   bool FirstContact;
   bool StartedGroundRun;
@@ -366,7 +366,7 @@ class JSBSIM_API FGLGear : public FGForce
   bool Castered;
   bool StaticFriction;
   std::string name;
-  double AGL;
+  double AGL; // Height above ground level
 
   BrakeGroup  eBrakeGrp;
   ContactType eContactType;