auto-detect controller

sim/unitree_sdk2py_bridge.py

@@ -280,12 +280,16 @@ class UnitreeSdk2Bridge:
         pygame.init()
         pygame.joystick.init()
         joystick_count = pygame.joystick.get_count()
-        if joystick_count > 0:
-            self.joystick = pygame.joystick.Joystick(device_id)
-            self.joystick.init()
-        else:
-            print("No gamepad detected.")
-            sys.exit()
+        if joystick_count == 0:
+            print("No gamepad detected — running without joystick.")
+            self.joystick = None
+            return
+        if device_id >= joystick_count:
+            print(f"Joystick device_id={device_id} out of range ({joystick_count} found) — using device 0.")
+            device_id = 0
+        self.joystick = pygame.joystick.Joystick(device_id)
+        self.joystick.init()
+        print(f"Joystick connected: {self.joystick.get_name()}")
 
         if js_type == "xbox":
             if sys.platform.startswith("linux"):