diff --git a/src/CMakeLists.txt b/src/CMakeLists.txt
index 93fe9bc18a1a5d82fb1a700e6194e458eb51f514..f146f97a9495155379db9436128baa12789a4b1d 100644
--- a/src/CMakeLists.txt
+++ b/src/CMakeLists.txt
@@ -253,6 +253,7 @@ SET(HDRS
     constraint_odom_3D.h
     constraint_point_2D.h
     constraint_point_to_line_2D.h
+    constraint_quaternion_absolute.h
     constraint_relative_2D_analytic.h
     feature_corner_2D.h
     feature_gps_fix.h
diff --git a/src/constraint_quaternion_absolute.h b/src/constraint_quaternion_absolute.h
new file mode 100644
index 0000000000000000000000000000000000000000..60a1f8e09a2f21b0a74db06eeb5010f1e504e206
--- /dev/null
+++ b/src/constraint_quaternion_absolute.h
@@ -0,0 +1,66 @@
+/**
+ * \file constraint_quaternion_absolute.h
+ *
+ *  Created on: Dec 15, 2017
+ *      \author: AtDinesh
+ */
+
+#ifndef CONSTRAINT_QUATERNION_ABSOLUTE_H_
+#define CONSTRAINT_QUATERNION_ABSOLUTE_H_
+
+//Wolf includes
+#include "constraint_autodiff.h"
+#include "frame_base.h"
+
+
+namespace wolf {
+
+WOLF_PTR_TYPEDEFS(ConstraintQuaternionAbsolute);
+
+//class
+class ConstraintQuaternionAbsolute: public ConstraintAutodiff<ConstraintQuaternionAbsolute,3,4>
+{
+    public:
+
+        ConstraintQuaternionAbsolute(StateBlockPtr _sb_ptr, bool _apply_loss_function = false, ConstraintStatus _status = CTR_ACTIVE) :
+            ConstraintAutodiff<ConstraintQuaternionAbsolute,3,4>(CTR_BLOCK_ABS, nullptr, nullptr, nullptr, nullptr, nullptr, _apply_loss_function, _status, _sb_ptr)
+        {
+            setType("FIX Q");
+        }
+
+        virtual ~ConstraintQuaternionAbsolute() = default;
+
+        template<typename T>
+        bool operator ()(const T* const _o, T* _residuals) const;
+
+        virtual JacobianMethod getJacobianMethod() const override
+        {
+            return JAC_AUTO;
+        }
+
+};
+
+template<typename T>
+inline bool ConstraintQuaternionAbsolute::operator ()(const T* const _o, T* _residuals) const
+{
+
+    // states
+    Eigen::Quaternion<T>    q(_o);
+
+    // measurements
+    Eigen::Quaternions  q_measured(getMeasurement().data() + 0);
+
+    // error
+    Eigen::Matrix<T, 3, 1> er;
+    er        = q2v(q.conjugate() * q_measured.cast<T>());
+
+    // residual
+    Eigen::Map<Eigen::Matrix<T, 3, 1>> res(_residuals);
+    res               = getFeaturePtr()->getMeasurementSquareRootInformationUpper().cast<T>() * er;
+
+    return true;
+}
+
+} // namespace wolf
+
+#endif