LuGre section not mandatory

robotology · Nov 7, 2024 · a0168f1 · a0168f1
1 parent 111db45
commit a0168f1
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Showing 3 changed files with 29 additions and 22 deletions.
diff --git a/src/libraries/icubmod/embObjMotionControl/embObjMotionControl.cpp b/src/libraries/icubmod/embObjMotionControl/embObjMotionControl.cpp
@@ -1380,14 +1380,14 @@ bool embObjMotionControl::init()
         jconfig.impedance.offset    = 0;
 
         jconfig.lugre_params.Km     = _lugre_params[logico].Km;
-		jconfig.lugre_params.Kw     = _lugre_params[logico].Kw;
-		jconfig.lugre_params.S0     = _lugre_params[logico].S0;
-		jconfig.lugre_params.S1     = _lugre_params[logico].S1;
-		jconfig.lugre_params.Vth    = _lugre_params[logico].Vth;
-		jconfig.lugre_params.Fc_pos = _lugre_params[logico].Fc_pos;
-		jconfig.lugre_params.Fc_neg = _lugre_params[logico].Fc_neg;
-		jconfig.lugre_params.Fs_pos = _lugre_params[logico].Fs_pos;
-		jconfig.lugre_params.Fs_neg = _lugre_params[logico].Fs_neg;
+        jconfig.lugre_params.Kw     = _lugre_params[logico].Kw;
+        jconfig.lugre_params.S0     = _lugre_params[logico].S0;
+        jconfig.lugre_params.S1     = _lugre_params[logico].S1;
+        jconfig.lugre_params.Vth    = _lugre_params[logico].Vth;
+        jconfig.lugre_params.Fc_pos = _lugre_params[logico].Fc_pos;
+        jconfig.lugre_params.Fc_neg = _lugre_params[logico].Fc_neg;
+        jconfig.lugre_params.Fs_pos = _lugre_params[logico].Fs_pos;
+        jconfig.lugre_params.Fs_neg = _lugre_params[logico].Fs_neg;
 
         _cacheImpedance[logico].stiffness = jconfig.impedance.stiffness;
         _cacheImpedance[logico].damping   = jconfig.impedance.damping;

diff --git a/src/libraries/icubmod/embObjMotionControl/eomcParser.cpp b/src/libraries/icubmod/embObjMotionControl/eomcParser.cpp
@@ -2482,8 +2482,13 @@ bool Parser::parseLugreGroup(yarp::os::Searchable &config,std::vector<lugreParam
 
     if(lugreGroup.isNull())
     {
-        yError() <<"embObjMC BOARD " << _boardname << "fromConfig(): Error: no LUGRE group found in config file, returning";
-        return false;
+        for (int j = 0; j<_njoints; ++j)
+        {
+            lugre[j].S0 = 0.0;
+        }
+
+        yWarning() <<"embObjMC BOARD " << _boardname << "fromConfig(): Warning: no LUGRE group found in config file, returning";
+        return true;
     }
 
 

diff --git a/src/libraries/icubmod/embObjMotionControl/eomcParser.h b/src/libraries/icubmod/embObjMotionControl/eomcParser.h
@@ -510,20 +510,22 @@ typedef struct
     impedanceLimits_t limits;
 } impedanceParameters_t;
 
+
+// LuGre friction model parameters
 typedef struct
 {
-    double Km;
-    double Kw;
-    double S0; 
-    double S1;
-    double Vth;
-    double Fc_pos;
-    double Fc_neg;
-    double Fs_pos;
-    double Fs_neg;
-    double tbd0;
-    double tbd1;
-    double tbd2;
+    double Km;     // Motor torque constant (not strictly LuGre) but required to compute the net torque
+    double Kw;     // Viscous friction constant
+    double S0;     // LuGre bristle analogy eleastic constant
+    double S1;     // LuGre bristle analogy viscous constant
+    double Vth;    // Stribeck velocity threshold
+    double Fc_pos; // Coulomb friction constant (positive rotation)
+    double Fc_neg; // Coulomb friction constant (negative rotation)
+    double Fs_pos; // Stribeck friction constant (positive rotation)
+    double Fs_neg; // Stribeck friction constant (negative rotation)
+    double tbd0;   // for future use?
+    double tbd1;   // for future use?
+    double tbd2;   // for future use? 
 } lugreParameters_t;
 
 typedef struct