diff --git a/src/segway_RMP400.cpp b/src/segway_RMP400.cpp
index 1ddb630f2a22184508cbdc7fbba70f837ae7c17d..de5f2456bf86613f38cf93e3b157c7727ba4ad9b 100644
--- a/src/segway_RMP400.cpp
+++ b/src/segway_RMP400.cpp
@@ -192,13 +192,13 @@ CSegwayRMP400::get_yaw_displacement()
 {
     need_to_be_connected();
 
-    float  yaw_displacement_mts = (segways_[0]->get_yaw_displacement() +
+    float  yaw_displacement_tmp = (segways_[0]->get_yaw_displacement() +
                                    segways_[1]->get_yaw_displacement()) / 2;
 
     if (use_correction_wheel_factor_)
-        fix_with_wheel_factor(yaw_displacement_mts);
+        fix_with_wheel_factor(yaw_displacement_tmp);
 
-    yaw_displacement_ = yaw_displacement_mts * 2 * PI; // convert to radians
+    yaw_displacement_ = yaw_displacement_tmp * 2 * PI; // convert to radians
     return yaw_displacement_;
 }