diff --git a/src/MindVisionMain.cpp b/src/MindVisionMain.cpp
index 1250ebc..7ce0269 100644
--- a/src/MindVisionMain.cpp
+++ b/src/MindVisionMain.cpp
@@ -25,7 +25,7 @@ void output_control_data(const cv::Point2f* ballistic_point,
                         bool use_ttl) {
     // Only send data when TTL is enabled, meets frame interval, and has valid target
     if (use_ttl && frame_counter % 5 == 0 && ballistic_point != nullptr) {
-        std::string send_str;
+        std::ostringstream send_str;
 
         // Calculate offset (based on actual image center)
         int ballistic_offset_x = static_cast<int>(ballistic_point->x - img_center.x);
@@ -37,11 +37,13 @@ void output_control_data(const cv::Point2f* ballistic_point,
         else if (target_color == "blue") simplified_color = "b";
 
         // Construct send string
-        send_str = "s " + simplified_color + " " + std::to_string(ballistic_offset_x) + " " + std::to_string(ballistic_offset_y);
+        send_str << "s " << simplified_color << " " << std::to_string(ballistic_offset_x) << " " << std::to_string(ballistic_offset_y);
 
         // Send data
         if (ttl_communicator != nullptr) {
-            ttl_communicator->send_data(send_str);
+            ttl_communicator->send_data(send_str.str());
+        }else{
+            std::cerr << "Error: TTLCommunicator is a null pointer!" << std::endl;
         }
     }
 }