diff --git a/demos/demo_imuDock.cpp b/demos/demo_imuDock.cpp
index b9d4db8a650c799465f8f176156a55d065e884f9..8efaf13ee55345081da9f72551105627e64887e9 100644
--- a/demos/demo_imuDock.cpp
+++ b/demos/demo_imuDock.cpp
@@ -272,9 +272,9 @@ int main(int argc, char** argv)
     #ifdef ADD_KF3
         Eigen::MatrixXd cov_KF1(16,16), cov_KF2(16,16), cov_KF3(16,16);
 
-        problem->getFrameCovariance(KF1, cov_KF1);
-        problem->getFrameCovariance(KF2, cov_KF2);
-        problem->getFrameCovariance(KF3, cov_KF3);
+        problem->getCovariance(KF1, cov_KF1);
+        problem->getCovariance(KF2, cov_KF2);
+        problem->getCovariance(KF3, cov_KF3);
 
         Eigen::Matrix<double, 16, 1> stdev_KF1, stdev_KF2, stdev_KF3;
 
@@ -288,8 +288,8 @@ int main(int argc, char** argv)
     #else
         Eigen::MatrixXd cov_KF1(16,16), cov_KF2(16,16);
 
-        problem->getFrameCovariance(KF1, cov_KF1);
-        problem->getFrameCovariance(KF2, cov_KF2);
+        problem->getCovariance(KF1, cov_KF1);
+        problem->getCovariance(KF2, cov_KF2);
 
         Eigen::Matrix<double, 16, 1> stdev_KF1, stdev_KF2;
 
diff --git a/demos/demo_imuDock_autoKFs.cpp b/demos/demo_imuDock_autoKFs.cpp
index 6b8fee70fa055ecfa00bc9317d4d427fdea71236..910ad964d7caf0fd05e837eaf4eeda1dcc55237a 100644
--- a/demos/demo_imuDock_autoKFs.cpp
+++ b/demos/demo_imuDock_autoKFs.cpp
@@ -284,7 +284,7 @@ int main(int argc, char** argv)
     {
         if(frame->isKey())
         {
-            problem->getFrameCovariance(frame, cov_KF);
+            problem->getCovariance(frame, cov_KF);
             stdev_KF = cov_KF.diagonal().array().sqrt();
             #ifdef OUTPUT_RESULTS
                 checking << frame->getTimeStamp().get() << "\t" << frame->getState().transpose() << "\t" << stdev_KF.transpose() << std::endl;
diff --git a/demos/demo_imuPlateform_Offline.cpp b/demos/demo_imuPlateform_Offline.cpp
index 7fd1d9488c9ff3b9625aa8b2e6c9fb6938f1f850..f7bcd12c01205f08ab1349622104e206299b83ff 100644
--- a/demos/demo_imuPlateform_Offline.cpp
+++ b/demos/demo_imuPlateform_Offline.cpp
@@ -242,7 +242,7 @@ int main(int argc, char** argv)
             ts = frmIMU_ptr->getTimeStamp();
 
             //get data from covariance blocks
-            wolf_problem_ptr_->getFrameCovariance(frmIMU_ptr, covX);
+            wolf_problem_ptr_->getCovariance(frmIMU_ptr, covX);
             wolf_problem_ptr_->getCovarianceBlock(frmIMU_ptr->getV(), frmIMU_ptr->getV(), cov3);
             covX.block(7,7,3,3) = cov3;
             wolf_problem_ptr_->getCovarianceBlock(frmIMU_ptr->getAccBias(), frmIMU_ptr->getAccBias(), cov3);
diff --git a/demos/demo_imu_constrained0.cpp b/demos/demo_imu_constrained0.cpp
index 3837895eb78d85b15dd9a8818b4b459ca425aee9..1ccc09d1aea94d80fc214f001bbe0954c454a479 100644
--- a/demos/demo_imu_constrained0.cpp
+++ b/demos/demo_imu_constrained0.cpp
@@ -305,7 +305,7 @@ int main(int argc, char** argv)
             ts = frmIMU_ptr->getTimeStamp();
 
             //get data from covariance blocks
-            wolf_problem_ptr_->getFrameCovariance(frmIMU_ptr, covX);
+            wolf_problem_ptr_->getCovariance(frmIMU_ptr, covX);
             wolf_problem_ptr_->getCovarianceBlock(frmIMU_ptr->getV(), frmIMU_ptr->getV(), cov3);
             covX.block(7,7,3,3) = cov3;
             wolf_problem_ptr_->getCovarianceBlock(frmIMU_ptr->getAccBias(), frmIMU_ptr->getAccBias(), cov3);
diff --git a/test/gtest_factor_imu.cpp b/test/gtest_factor_imu.cpp
index a87084141907d2deac30522073015790db9966bf..5509a069b9d8ae5d3faeab4977db2763376d65b6 100644
--- a/test/gtest_factor_imu.cpp
+++ b/test/gtest_factor_imu.cpp
@@ -2170,7 +2170,7 @@ TEST_F(FactorImu_ODOM_biasTest_Move_NonNullBiasRotY, VarB1B2_InvarP1Q1V1P2Q2V2_i
     MatrixXd covX(10,10);
         
     //get data from covariance blocks
-    problem->getFrameCovariance(last_KF, covX);
+    problem->getCovariance(last_KF, covX);
 
     for(int i = 0; i<10; i++)
         cov_stdev(i) = ( covX(i,i)? 2*sqrt(covX(i,i)):0); //if diagonal value is 0 then store 0 else store 2*sqrt(diag_value)
@@ -2216,7 +2216,7 @@ TEST_F(FactorImu_ODOM_biasTest_Move_NonNullBiasRotY, VarB1B2V2_InvarP1Q1V1P2Q2_i
     MatrixXd covX(10,10);
         
     //get data from covariance blocks
-    problem->getFrameCovariance(last_KF, covX);
+    problem->getCovariance(last_KF, covX);
 
     for(int i = 0; i<10; i++)
         cov_stdev(i) = ( covX(i,i)? 2*sqrt(covX(i,i)):0); //if diagonal value is 0 then store 0 else store 2*sqrt(diag_value)
@@ -2381,7 +2381,7 @@ TEST_F(FactorImu_ODOM_biasTest_Move_NonNullBiasRotY, VarB1B2P2Q2V2_InvarP1Q1V1_i
     MatrixXd covX(10,10);
         
     //get data from covariance blocks
-    problem->getFrameCovariance(last_KF, covX);
+    problem->getCovariance(last_KF, covX);
 
     for(int i = 0; i<10; i++)
         cov_stdev(i) = ( covX(i,i)? 2*sqrt(covX(i,i)):0); //if diagonal value is 0 then store 0 else store 2*sqrt(diag_value)
@@ -2438,7 +2438,7 @@ TEST_F(FactorImu_ODOM_biasTest_Move_NonNullBiasRotY, VarQ1B1B2P2Q2_InvarP1V1V2_i
     MatrixXd covX(10,10);
         
     //get data from covariance blocks
-    problem->getFrameCovariance(last_KF, covX);
+    problem->getCovariance(last_KF, covX);
 
     for(int i = 0; i<10; i++)
         cov_stdev(i) = ( covX(i,i)? 2*sqrt(covX(i,i)):0); //if diagonal value is 0 then store 0 else store 2*sqrt(diag_value)
@@ -2498,7 +2498,7 @@ TEST_F(FactorImu_ODOM_biasTest_Move_NonNullBiasRotXY, VarQ1B1B2P2Q2_InvarP1V1V2_
     MatrixXd covX(10,10);
         
     //get data from covariance blocks
-    problem->getFrameCovariance(last_KF, covX);
+    problem->getCovariance(last_KF, covX);
 
     for(int i = 0; i<10; i++)
         cov_stdev(i) = ( covX(i,i)? 2*sqrt(covX(i,i)):0); //if diagonal value is 0 then store 0 else store 2*sqrt(diag_value)
@@ -2549,7 +2549,7 @@ TEST_F(FactorImu_ODOM_biasTest_Move_NonNullBiasRot, VarB1B2_InvarP1Q1V1P2Q2V2_in
     MatrixXd covX(10,10);
         
     //get data from covariance blocks
-    problem->getFrameCovariance(last_KF, covX);
+    problem->getCovariance(last_KF, covX);
 
     for(int i = 0; i<10; i++)
         cov_stdev(i) = ( covX(i,i)? 2*sqrt(covX(i,i)):0); //if diagonal value is 0 then store 0 else store 2*sqrt(diag_value)
@@ -2595,7 +2595,7 @@ TEST_F(FactorImu_ODOM_biasTest_Move_NonNullBiasRot, VarB1B2V2_InvarP1Q1V1P2Q2_in
     MatrixXd covX(10,10);
         
     //get data from covariance blocks
-    problem->getFrameCovariance(last_KF, covX);
+    problem->getCovariance(last_KF, covX);
 
     for(int i = 0; i<10; i++)
         cov_stdev(i) = ( covX(i,i)? 2*sqrt(covX(i,i)):0); //if diagonal value is 0 then store 0 else store 2*sqrt(diag_value)
@@ -2754,7 +2754,7 @@ TEST_F(FactorImu_ODOM_biasTest_Move_NonNullBiasRot, VarB1B2P2Q2V2_InvarP1Q1V1_in
     MatrixXd covX(10,10);
         
     //get data from covariance blocks
-    problem->getFrameCovariance(last_KF, covX);
+    problem->getCovariance(last_KF, covX);
 
     for(int i = 0; i<10; i++)
         cov_stdev(i) = ( covX(i,i)? 2*sqrt(covX(i,i)):0); //if diagonal value is 0 then store 0 else store 2*sqrt(diag_value)