diff --git a/unilabos_msgs/action/LiquidHandlerAspirate.action b/unilabos_msgs/action/LiquidHandlerAspirate.action
index 9ba17068..f03ad07a 100644
--- a/unilabos_msgs/action/LiquidHandlerAspirate.action
+++ b/unilabos_msgs/action/LiquidHandlerAspirate.action
@@ -5,7 +5,7 @@ float64[] flow_rates
 geometry_msgs/Point[] offsets
 float64[] liquid_height
 float64[] blow_out_air_volume
-string spread
+string spread="wide"
 ---
 bool success
 ---
\ No newline at end of file
diff --git a/unilabos_msgs/action/LiquidHandlerDispense.action b/unilabos_msgs/action/LiquidHandlerDispense.action
index f934aec2..ba5360ae 100644
--- a/unilabos_msgs/action/LiquidHandlerDispense.action
+++ b/unilabos_msgs/action/LiquidHandlerDispense.action
@@ -1,4 +1,3 @@
-# Bio
 # 请求字段
 Resource[] resources
 float64[] vols
@@ -6,7 +5,7 @@ int32[] use_channels
 float64[] flow_rates
 geometry_msgs/Point[] offsets
 int32[] blow_out_air_volume
-string spread
+string spread="wide"
 ---
 # 结果字段
 bool success