diff --git a/include/jrl/walkgen/pgtypes.hh b/include/jrl/walkgen/pgtypes.hh
index 5149a65e1978d650c107716599664a4a0d6d4f54..b34af62f409fba2566387fd33b8b8aabbba61ac9 100644
--- a/include/jrl/walkgen/pgtypes.hh
+++ b/include/jrl/walkgen/pgtypes.hh
@@ -137,6 +137,15 @@ namespace PatternGeneratorJRL
   typedef struct LinearConstraintInequality_s
     LinearConstraintInequality_t;
 
+  /// Linear constraints with variable feet placement.
+  struct LinearConstraintInequalityFreeFeet_s
+  {
+    MAL_MATRIX(D,double);
+    MAL_MATRIX(Dc,double);
+    int StepNumber;
+  };
+  typedef struct LinearConstraintInequalityFreeFeet_s
+    LinearConstraintInequalityFreeFeet_t;
 
 }
 #endif