# Blickfeld ROS package
This package provides an ROS node and a nodelet for publishing PointCloud2 messages from Blickfeld LiDAR devices.  
The driver is not yet available publicly. Please request the sources from the Blickfeld Sales department.

## Supported devices
The Blickfeld ROS driver supports all currently available Blickfeld LiDARs, such as Cube 1 and Cube Range 1.

## Supported ROS Distributions
The Blickfeld ROS driver supports the following distributions
* ROS Melodic Morenia (Ubuntu 18.04)
* ROS Noetic Ninjemys (Ubuntu 20.04)

## Dependencies
To install the Blickfeld ROS driver, please make sure that the following dependencies are installed on your system.

* [blickfeld-scanner-library (BSL) ](https://docs.blickfeld.com/cube/latest/external/blickfeld-scanner-lib/install.html) with system-wide protobuf installation. This package has been tested using **BSL Version 2.13.0**

* [ROS Melodic Installation](http://wiki.ros.org/melodic/Installation/Ubuntu) with Ubuntu 18.04 **/**
  [ROS Noetic Installation](http://wiki.ros.org/noetic/Installation/Ubuntu) with Ubuntu 20.04

* [diagnostic_updater](https://index.ros.org/p/diagnostic_updater/)  can be acquired via your distribution's package manager, ${ROS_DISTRO} should be your ROS version. (e.g. melodic or noetic)

      $ sudo apt install ros-${ROS_DISTRO}-diagnostic-updater
      $ sudo apt install ros-${ROS_DISTRO}-diagnostic-msgs

   or via

      $ rosdep update
      $ rosdep install --from-paths src --ignore-src -r -y

## Build
Before building ensure that your ROS DISTRO is sourced. You will need to run this command on every new shell you open to have access to the ROS commands. ${ROS_DISTRO} should be your ROS version. (e.g. melodic or noetic)

    $ source /opt/ros/${ROS_DISTRO}/setup.bash

To build the ROS driver, request the ROS driver from the Blickfeld Sales department and decompress the archive into your ROS catkin workspace.

Run

    $ catkin build

or respectively

    $ catkin build blickfeld_driver

You may use ```catkin_make``` instead of ```catkin build``` as well.

## Running the Blickfeld ROS node
You can start the Blickfeld driver as either a node or a nodelet. For the node, you can use the launch file

    $ live_scanner.launch

and for the nodelet, the

    $ live_scanner_nodelet.launch

is provided.

You can launch the ROS driver in a **DHCP** controlled Network by providing the Hostname of the LiDAR device (you can check and set the Hostname in the WebGUI of the device) (**Make sure you have sourced your workspace**) e.g.:

    $ roslaunch blickfeld_driver live_scanner.launch host:=cube-0028

or respectively

    $ roslaunch blickfeld_driver live_scanner_nodelet.launch host:=cube-0028  

You should now be able to see a PointCloud2 in Rviz on the `/bf_lidar/points_raw` topic.

If you connect the LiDAR directly to your PC or don't have a **DHCP** Server you can launch the driver by using the IP configured in the WebGUI of the Device or the Fallback-IP of the Device  
(**Make sure you sourced your workspace and adjusted your network-settings accordingly**) e.g.:

    $ roslaunch blickfeld_driver live_scanner.launch host:=192.168.26.26

or respectively

    $ roslaunch blickfeld_driver live_scanner_nodelet.launch host:=192.168.26.26

By default we do not start RViz, set the rviz parameter to true if you want to start RViz with the Blickfeld ROS driver:

    $ roslaunch blickfeld_driver live_scanner.launch host:=192.168.26.26 rviz:=true

See the table with all available Parameters and there default configuration.

### Parameters
Both launch files have arguments you can use:

| Argument | Default | Note |
| ------ | ------ | ------ |
| **host** (required) | | The host name or the IP of the device you want to publish the point clouds from, e.g., `cube-0028`, `192.168.26.26`. |
| node_name | `bf_lidar` | Name of this ROS node. |
| point_cloud_out | `$(arg node_name)/points_raw` | Topic to publish the  PointCloud2 message to. |
| remap | `true` | Remap this node’s input/output topics to commonly used ones. <br/>If `false`, canonical names in the form of `$(arg node_name)/foo_(in/out)` are used, depending on whether a topic is an input or and output topic. |
| lidar_frame_id | `lidar` | The ROS TF where the point cloud should be in. |
| rviz | `false` | Start rviz if this argument is true. |
| use_lidar_timestamp | `true` | Set to true if the timestamp in the ROS point cloud message should be generated from the device timestamp; otherwise the timestamp will be the ROS time when the frame was received on ROS. |
| publish_intensities | `true` | Set to true if the PointCloud2 message should contain intensities. |
| publish_ambient_light | `false` | Set to true if the PointCloud2 message should contain the ambient light level. |
| publish_explicit_range | `false` | Set to true if the PointCloud2 message should contain the `range` field. |
| publish_no_return_points | `false` | Set to true if the PointCloud2 message should contain points in a given range for pulses without a return. |
| no_return_point_range | `1.0` | Dummy range for points of pulses without a return. |
| returns_publishing_options | `strongest` | different options to publish multiple returns, possible values are: `strongest` `first` `last` and `all`, in case of `all`, the field `return_id` (ID for each returned point) is added to the point cloud. |
| publish_time_delta | `false` | If `true`, the PointCloud2 message will contain the timestamp field per point to represent the time offset from the start of the frame. |
| publish_point_id | `false` | Add the `scanline_id` field, the `scanline_point_index` field (= the point’s number in the scan line), and the `point_id` (= frame-global point ID) to PointCloud2 message. <br/> If the device is configured to return multiple return points (multiple reflections), all these three IDs will be identical; only the `return_id` will differ. |

## License
This package is released under a [BSD 3-Clause License](LICENSE) (see also [https://opensource.org/licenses/BSD-3-Clause](https://opensource.org/licenses/BSD-3-Clause))