diff --git a/libraries/AP_RobotisServo/AP_RobotisServo.cpp b/libraries/AP_RobotisServo/AP_RobotisServo.cpp
index 337b8a0c74..8b4160d493 100644
--- a/libraries/AP_RobotisServo/AP_RobotisServo.cpp
+++ b/libraries/AP_RobotisServo/AP_RobotisServo.cpp
@@ -35,6 +35,8 @@
 */
 
 #include <AP_HAL/AP_HAL.h>
+#include <AP_Math/AP_Math.h>
+#include <AP_SerialManager/AP_SerialManager.h>
 #include <SRV_Channel/SRV_Channel.h>
 
 #include "AP_RobotisServo.h"
diff --git a/libraries/AP_RobotisServo/AP_RobotisServo.h b/libraries/AP_RobotisServo/AP_RobotisServo.h
index f28d91fd4e..a97b609d81 100644
--- a/libraries/AP_RobotisServo/AP_RobotisServo.h
+++ b/libraries/AP_RobotisServo/AP_RobotisServo.h
@@ -19,7 +19,6 @@
 #pragma once
 
 #include <AP_HAL/AP_HAL.h>
-#include <AP_SerialManager/AP_SerialManager.h>
 #include <AP_Param/AP_Param.h>
 
 class AP_RobotisServo {