diff --git a/main.py b/main.py
index a78c449..9228697 100644
--- a/main.py
+++ b/main.py
@@ -97,7 +97,7 @@ PASSWORD = None
 # 服务器连接参数
 SERVER_IP = "www.shelingxingqiu.com"
 SERVER_PORT = 50005
-HEARTBEAT_INTERVAL = 60  # 心跳间隔（秒）
+HEARTBEAT_INTERVAL = 6  # 心跳间隔（秒）
 
 # 激光校准配置
 CONFIG_FILE = "/root/laser_config.json"
@@ -154,8 +154,8 @@ LASER_OFF_CMD = bytes([0xAA, MODULE_ADDR, 0x01, 0xBE, 0x00, 0x01, 0x00, 0x00, 0x
 
 # 相机标定参数（用于距离估算）
 # FOCAL_LENGTH_PIX = 3800.0    # 焦距（像素）
-FOCAL_LENGTH_PIX = 2200.0  # 焦距（像素）
-REAL_RADIUS_CM = 15  # 靶心实际半径（厘米）
+FOCAL_LENGTH_PIX = 1900.0    # 焦距（像素）
+REAL_RADIUS_CM = 15          # 靶心实际半径（厘米）
 
 # TCP 连接状态
 tcp_connected = False
@@ -470,29 +470,35 @@ def parse_packet(data: bytes):
 
 
 def tcp_send_raw(data: bytes, max_retries=2) -> bool:
-    """通过 4G 模块的 AT 指令发送原始 TCP 数据包"""
     global tcp_connected
     if not tcp_connected:
         return False
+
     with uart4g_lock:
-        for attempt in range(max_retries):
+        for _ in range(max_retries):
             cmd = f'AT+MIPSEND=0,{len(data)}'
-            if ">" not in at(cmd, ">", 1500):
-                time.sleep_ms(100)
+            if ">" not in at(cmd, ">", 2000):
+                time.sleep_ms(50)
                 continue
 
-            time.sleep_ms(10)
-            full = data + b"\x1A"  # AT 指令结束符
-            try:
-                sent = uart4g.write(full)
-                if sent != len(full):
+            # 关键：确保把 data 全部写出去
+            total = 0
+            while total < len(data):
+                n = uart4g.write(data[total:])
+                if not n or n < 0:
+                    time.sleep_ms(1)
                     continue
-            except:
-                continue
+                total += n
 
-            if "OK" in at("", "OK", 1000):
+            # 关键：再发结束符（不算进 payload）
+            uart4g.write(b"\x1A")
+
+            # 等发送完成确认（不同固件可能是 SEND OK / OK / +MIPSEND）
+            r = at("", "OK", 5000)
+            if ("SEND OK" in r) or ("OK" in r) or ("+MIPSEND" in r):
                 return True
-            time.sleep_ms(100)
+
+            time.sleep_ms(50)
 
         return False
 
@@ -684,10 +690,7 @@ def detect_circle(frame):
         circularity = 4 * np.pi * area / (perimeter ** 2)
         if circularity > 0.75 and len(cnt) >= 5:
             center, axes, angle = cv2.fitEllipse(cnt)
-            radius = axes[0]
-            if axes[1] < radius:
-                radius = axes[1]
-            radius /= 2
+            radius = (axes[0] + axes[1]) / 4
             best_center = (int(center[0]), int(center[1]))
             best_radius = int(radius)
             best_radius1 = best_radius
@@ -790,7 +793,13 @@ def tcp_main():
                 time.sleep_ms(20)
                 continue
 
-            data = uart4g.read()
+            if not uart4g_lock.try_acquire():
+                time.sleep_ms(1)
+                continue
+            try:
+                data = uart4g.read()
+            finally:
+                uart4g_lock.release()
             if data:
                 rx_buf += data
                 # 解析 +MIPURC 消息
@@ -1351,7 +1360,7 @@ def cmd_str():
 
     # 初始化硬件
     init_ina226()
-    # load_laser_point()
+    load_laser_point()
     disp = display.Display()
     cam = camera.Camera(640, 480)