diff --git a/src/shared/particle_dynamics/solid_dynamics/slender_structure_dynamics.h b/src/shared/particle_dynamics/solid_dynamics/slender_structure_dynamics.h
index d1a2db0182..b21b014bfc 100644
--- a/src/shared/particle_dynamics/solid_dynamics/slender_structure_dynamics.h
+++ b/src/shared/particle_dynamics/solid_dynamics/slender_structure_dynamics.h
@@ -265,8 +265,10 @@ namespace SPH
     
 			Vecd local_dpseudo_n_d2t = transformation_matrix_[index_i] * dpseudo_n_d2t_[index_i];
             Vecd local_dpseudo_b_n_d2t = transformation_matrix_[index_i] * dpseudo_b_n_d2t_[index_i];
-            dangular_b_vel_dt_[index_i] = getRotationFromPseudoNormalForSmallDeformation_b(Vec3d(local_dpseudo_b_n_d2t), Vec3d(local_dpseudo_n_d2t), Vec3d(rotation_b_[index_i]), Vec3d(angular_b_vel_[index_i]), dt);
-            dangular_vel_dt_[index_i] = getRotationFromPseudoNormalForSmallDeformation(Vec3d(local_dpseudo_b_n_d2t), Vec3d(local_dpseudo_n_d2t), Vec3d(rotation_[index_i]), Vec3d(angular_vel_[index_i]), dt);
+                        dangular_b_vel_dt_[index_i] = Vec3d(0.0, 0.0, dpseudo_b_n_d2t[0]);
+                        
+                        //getRotationFromPseudoNormalForSmallDeformation_b(Vec3d(local_dpseudo_b_n_d2t), Vec3d(local_dpseudo_n_d2t), Vec3d(rotation_b_[index_i]), Vec3d(angular_b_vel_[index_i]), dt);
+                        dangular_vel_dt_[index_i] = Vec3d(0.0, dpseudo_n_d2t[0], 0.0); // getRotationFromPseudoNormalForSmallDeformation(Vec3d(local_dpseudo_b_n_d2t), Vec3d(local_dpseudo_n_d2t), Vec3d(rotation_[index_i]), Vec3d(angular_vel_[index_i]), dt);
 			};
 
 			void update(size_t index_i, Real dt = 0.0);