# How to use to nodes at the same time

**URL:** <https://forum.hello-robot.com/t/how-to-use-to-nodes-at-the-same-time/781>\
**Category:** Ask\
**Created:** [August 3, 2023, 11:54am UTC](https://forum.hello-robot.com/t/how-to-use-to-nodes-at-the-same-time/781 "2023-08-03T11:54:09Z")\
**Posts on this page:** 2\
**Page:** 1

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**Author:** ![Humberto\_Andres\_Hida](https://yyz2.discourse-cdn.com/flex030/user_avatar/forum.hello-robot.com/humberto_andres_hida/32/524_2.png) [@Humberto\_Andres\_Hida](https://forum.hello-robot.com/u/Humberto_Andres_Hida)\
**Post date:** [August 3, 2023, 11:54am UTC](https://forum.hello-robot.com/t/how-to-use-to-nodes-at-the-same-time/781/1 "2023-08-03T11:54:09Z")

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Hi I want to ask how i can use the node of navigation, which i use with:

```auto
roslaunch stretch_navigation navigation.launch map_yaml:=${HELLO_FLEET_PATH}/maps/<map_name>.yaml

```

and the node of perception which I run with:  
`roslaunch stretch_deep_perception stretch_detect_objects.launch`

Because if I use the roslaunch to detect objects, the node of navigation stop working. The thing is that i have to run the navigation node to mode the robot with other node and in the samte time run the node of deep detection to find some objects.  
Please could you help me with this problem?

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<div class="post-metadata">

**Author:** ![Mohamed\_Fazil](https://yyz2.discourse-cdn.com/flex030/user_avatar/forum.hello-robot.com/mohamed_fazil/32/261_2.png) [@Mohamed\_Fazil](https://forum.hello-robot.com/u/Mohamed_Fazil)\
**Post date:** [August 3, 2023, 3:51pm UTC](https://forum.hello-robot.com/t/how-to-use-to-nodes-at-the-same-time/781/2 "2023-08-03T15:51:54Z")

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Hi @Humberto_Andres_Hida,  
I am guessing the issue is that both the launch you have described will launch the stretch\_drive node simultaneously, which would make either one of them fail because only one stretch\_driver node could run at an instance. I would recommend you comment out the stretch\_driver node inclusion [code block](https://github.com/hello-robot/stretch_ros/blob/noetic/stretch_deep_perception/launch/stretch_detect_objects.launch#L13:L17) in the [navigation.launch](https://github.com/hello-robot/stretch_ros/blob/noetic/stretch_navigation/launch/navigation.launch) or the [stretch\_detect\_objects.launch](https://github.com/hello-robot/stretch_ros/blob/noetic/stretch_deep_perception/launch/stretch_detect_objects.launch) file so that the stretch driver node is only launched once.