diff --git a/test/gtest_IMU.cpp b/test/gtest_IMU.cpp
index 59e2080cc47df7b4ebefb21036d46533b94a5c7e..2e06cb01420ae2c8d3aed65d9c7ea47bf1808e1b 100644
--- a/test/gtest_IMU.cpp
+++ b/test/gtest_IMU.cpp
@@ -238,7 +238,7 @@ class Process_Factor_IMU : public testing::Test
          */
         static MotionBuffer integrateDeltaTrajectory(const Quaternions& q0, const MatrixXs& motion, const VectorXs& bias_real, const VectorXs& bias_preint, Scalar dt, Matrix<Scalar, 9, 6>& J_D_b)
         {
-            MotionBuffer trajectory(6, 10, 9);
+            MotionBuffer trajectory;
             VectorXs    Delta(10);
             MatrixXs    M9(9,9), M6(6,6), J9(9,9), J96(9,6), V10(10,1), V6(6,1);
             Quaternions q;