# Error while installing Open RMF and question about integration with real robots (#143)

**URL:** <https://discourse.openrobotics.org/t/error-while-installing-open-rmf-and-question-about-integration-with-real-robots-143/44910>\
**Category:** Open-RMF General\
**Tags:** rmf-github-discuss\
**Created:** [February 23, 2022, 6:49pm UTC](https://discourse.openrobotics.org/t/error-while-installing-open-rmf-and-question-about-integration-with-real-robots-143/44910 "2022-02-23T18:49:38Z")\
**Posts on this page:** 2\
**Page:** 1

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**Author:** ![Archive-o-matic](https://sea2.discourse-cdn.com/flex022/user_avatar/discourse.openrobotics.org/archive-o-matic/32/26074_2.png) [@Archive-o-matic](https://discourse.openrobotics.org/u/Archive-o-matic)\
**Post date:** [February 23, 2022, 6:49pm UTC](https://discourse.openrobotics.org/t/error-while-installing-open-rmf-and-question-about-integration-with-real-robots-143/44910/1 "2022-02-23T18:49:38Z")

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Posted by @gregoryyts:

Hi. I’m trying to integrate Open RMF with some AMRs that are operating in a factory with ROS1(Melodic). My objective is to communicate the fleet manager with robots remotely. To do that I’m using Ubuntu 20.04, ROS1 Noetic, ROS2 Galactic and ros1\_bridge (to communicate ROS 1 and ROS 2), as it’s shown in image bellow

 ![Diagrama em branco](https://us1.discourse-cdn.com/flex022/uploads/ros/original/3X/1/c/1c00759193dccf92a171f29951fb0ea7fb90dfb5.png)

Basically, what I intend to do is run Open RMF in ROS Galactic, then stablish a communication between ROS Galactic and ROS Noetic via ros1\_bridge, and then communicate my ROS Noetic with ROS Melodic of the factory (everything is in the same network).

In order to do that, I developed an API, just as recommended [here](https://github.com/open-rmf/fleet_adapter_template) to run in my local ROS2. Is it right? I have seen some people talking about the usage of free\_fleet in order to put the fleet manager to work with real robots, but I don’t get what is the purpose of free\_fleet in this scenario, since I already have the Open RMF.

Anyway, I’m having problems with installation of open RMF too. I am following the steps indicated in [RMF Root Repository](https://github.com/open-rmf/rmf) to build from source, but when I run `rosdep install --from-paths src --ignore-src --rosdistro galactic -y`, I have the following output:

```auto
ERROR: the following packages/stacks could not have their rosdep keys resolved to system dependencies:
rmf_demos_bridges: Cannot locate rosdep definition for [python3-socketio]

```

Does anyone knows what could be the cause of this error and how to fix it?

Besides, when I run  
`cd ~/rmf_ws`  
`source /opt/ros/galactic/setup.bash`  
`colcon build --cmake-args -DCMAKE_BUILD_TYPE=Release`  
I have the following output:

```CMake
  By not providing "Findnlohmann_json.cmake" in CMAKE_MODULE_PATH this
  project has asked CMake to find a package configuration file provided by
  "nlohmann_json", but CMake did not find one.

  Could not find a package configuration file provided by "nlohmann_json"
  with any of the following names:

    nlohmann_jsonConfig.cmake
    nlohmann_json-config.cmake

  Add the installation prefix of "nlohmann_json" to CMAKE_PREFIX_PATH or set
  "nlohmann_json_DIR" to a directory containing one of the above files. If
  "nlohmann_json" provides a separate development package or SDK, be sure it
  has been installed.

---
Failed <<< rmf_api_msgs [0.70s, exited with code 1]
Aborted <<< rmf_dispenser_msgs [11.1s]           
Aborted <<< rmf_door_msgs [11.2s]
Aborted <<< rmf_building_map_msgs [11.6s]        
Aborted <<< nlohmann_json_schema_validator_vendor [2.99s]
Aborted <<< rmf_fleet_msgs [12.9s]               
Aborted <<< rmf_utils [21.6s]                    
Aborted <<< rmf_traffic_msgs [27.2s]                                    

Summary: 3 packages finished [27.4s]
  1 package failed: rmf_api_msgs
  7 packages aborted: nlohmann_json_schema_validator_vendor rmf_building_map_msgs rmf_dispenser_msgs rmf_door_msgs rmf_fleet_msgs rmf_traffic_msgs rmf_utils
  2 packages had stderr output: nlohmann_json_schema_validator_vendor rmf_api_msgs
  40 packages not processed

```

I don’t know where is the cause of this error either. Does anyone knows?

Here’s some important information:

- Operating system and version:  
Ubuntu 20.04
- OpenRMF version or commit hash  
Main
- ROS distribution:  
ROS Galactic
- ROS installation type:  
Via debian packages

---

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**Author:** ![Archive-o-matic](https://sea2.discourse-cdn.com/flex022/user_avatar/discourse.openrobotics.org/archive-o-matic/32/26074_2.png) [@Archive-o-matic](https://discourse.openrobotics.org/u/Archive-o-matic)\
**Post date:** [February 24, 2022, 4:25am UTC](https://discourse.openrobotics.org/t/error-while-installing-open-rmf-and-question-about-integration-with-real-robots-143/44910/2 "2022-02-24T04:25:39Z")

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Posted by @mxgrey:

> `rmf_demos_bridges: Cannot locate rosdep definition for [python3-socketio]`

This bug was recently found and should be fixed as of yesterday: [Fix rosdep key for demo bridges by xiyuoh · Pull Request #127 · open-rmf/rmf\_demos · GitHub](https://github.com/open-rmf/rmf_demos/pull/127)

> `Could not find a package configuration file provided by "nlohmann_json"`

This one surprises me, because [`rmf_api_msgs` does specify its dependency on `nlohmann-json-dev`](https://github.com/open-rmf/rmf_api_msgs/blob/main/rmf_api_msgs/package.xml#L11). Using your earlier `rosdep install ... ` command [should have therefore installed `nlohmann-json3-dev`](https://github.com/ros/rosdistro/blob/97a12c39a1439326dc0da525c2ec64093e68d32f/rosdep/base.yaml#L6270).

The only thing I can think of is maybe your rosdep hasn’t been updated since the `nlohmann-json-dev` key was added to rosdistro? You could try running `$ rosdep update` and then rerun the `rosdep install ... ` command to see if that fixes it.

Edit: But if the `nlohmann-json-dev` key didn’t exist in your rosdistro cache, then I think you should have gotten the same error that you got for `python3-socketio`… So I really can’t think of a reason for that failure… 🤔

* * *

Edited by @mxgrey at 2022-02-24T04:28:26Z