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diff --git a/src/modules/robot/Robot.cpp b/src/modules/robot/Robot.cpp
index aa28a49..c8e3215 100644 (file)
--- a/src/modules/robot/Robot.cpp
+++ b/src/modules/robot/Robot.cpp
@@ -1455,7 +1455,8 @@ bool Robot::append_arc(Gcode * gcode, const float target[], const float offset[]
         return false;
     }
 
-    // Scary math
+    // Scary math.
+    // We need to use arc_milestone here to get accurate arcs as previous machine_position may have been skipped due to small movements
     float center_axis0 = this->arc_milestone[this->plane_axis_0] + offset[this->plane_axis_0];
     float center_axis1 = this->arc_milestone[this->plane_axis_1] + offset[this->plane_axis_1];
     float linear_travel = target[this->plane_axis_2] - this->arc_milestone[this->plane_axis_2];