PILZ safety laser scanner PSENscan

Package: psen_scan_v2

The psen_scan_v2 package is a ROS integration driver for the PSENscan safety laser scanner product. It lets you integrate the laser scanner data into your ROS Environment easily. Using the standard [sensor_msgs/LaserScan][] message format ensures compatibility with other laserscan-post-processing nodes such as [gmapping][]. For a general overview, link collection and tutorials we refer to the ROS wiki page.

PSENscan firmware >= 3.1.0 is supported on the following models:

C++ standalone library

If you are interested in using the PSENscan safety laser scanner without ROS, please take a look at our C++ standalone library. You can read more about it in the standalone folder

Table of Contents

1. Installation
2. Usage
   • Parameters
   • Optional Parameters
   • Expert Parameters (optional)
   • Published Topics
   • TF Frames
   • Defining the scan range
3. Developer Information
   • Build Status
   • Branching model
   • Test concept
4. Migration

Installation

Needed Equipment: - PSENscan safety laser scanner - ROS Machine

To use the package, you can install prebuilt packages with

sudo apt install ros-$ROS_DISTRO-psen-scan-v2

Usage

To start reading data from the safety laser scanner and publishing scans execute roslaunch psen_scan_v2 psen_scan_v2.launch in a command line. This will launch the ROS Node with the default configuration.

If you wish to set parameters from the command line, add them to the end of the command as parameter:=value, separated by spaces.

roslaunch psen_scan_v2 psen_scan_v2.launch sensor_ip:=192.168.0.10

This example configures the safety laser scanner at 192.168.0.10 to send it´s frames to 192.168.0.20:3050.

In order to create an application with your own launch file, you can include the bringup.launch, where you can easily adjust the configuration parameters. A more detailed explanation can be found in the tutorials.

Parameters

sensor_ip (string, default: "192.168.0.10")
IP-Address of safety laser scanner.

Optional Parameters

tf_prefix (string, default: "laser_1")
Name of this scanner that can be changed to differentiate between multiple devices. By convention this is used as tf prefix.

angle_start (double, default: -2.398 (= -137.4 deg))
Start angle of measurement. (Radian)

angle_end (double, default: 2.398 (= 137.4 deg))
End angle of measurement. It is included in the measurements. (Radian)

intensities (bool, default: false)
Publish intensities. If this is enabled, the resolution needs to be increased (at least 0.2 deg).

resolution (double, default: 0.0017 (= 0.1 deg))
Scan angle resolution. (Radian) The value is rounded to a multiple of 0.1 deg and has to be in the range [0.1, 10] degrees.

Expert Parameters (optional)

host_ip (string, default: "auto")
IP-Address of host machine. The IP of the local machine is used by default.

host_udp_port_data (int, default: 55115)
UDP Port on which monitoring frames (scans) should be received.

host_udp_port_control (int, default: 55116)
UDP Port used to send commands (start/stop) and receive the corresponding replies.

fragmented_scans (bool, default: false)
Publish scan data as soon as a UDP packet is ready, do not wait for a full scan.

rviz (bool, default: true)
Start a preconfigured rviz visualizing the scan data.

Published Topics

/<name>/scan ([sensor_msgs/LaserScan][])

• If fragmented_scans is set to false (default) the driver will publish complete scan rounds from the PSENscan safety laser scanner as a single message.
• If fragmented_scans is enabled the driver will send the measurement data as soon as they arrive, instead of waiting for the scan round to be completed. This way the scan data is received sooner but is split into several sensor messages.

Hint 1: Scan rounds and fragments that contain no measurement data are not published. This can happen with smaller scan ranges.

Hint 2: Frequency of the laser scan messages is about 33hz for the combined and 200hz for the fragmented scans.

TF Frames

The location of the TF frames is shown in the image below. These names are defined by the aforementioned launchfile parameter name. Changing them is necessary for instance when running multiple scanners.

Defining the scan range

You can adjust the scan field to your needs by changing angle_start and angle_end. The published ([sensor_msgs/LaserScan][]) will only contain data within the given angle limits. Both limits are defined within the laser_1 frame as shown in the image below.

Developer Information

Build Status

Platform	Melodic	Noetic
CI
Buildfarm src
Buildfarm bin

Branching model

main is considered to be the active development branch, it targets the ROS distributions melodic and noetic.

Test concept

Migration

To update your ROS environment from the former psen_scan package (which supported firmware versions up to 3.0), please execute the following steps: 1. Update scanner firmware using PSENscan Configurator (unless the device has firmware 3.1 already) 2. Install the new ROS package sudo apt install ros-$ROS_DISTRO-psen-scan-v2 3. Replace the launch file arguments: * password and x_axis_rotation are obsolete and should be dropped * angle_start and angle_end are now in radians, in direction of the x axis of the scanner tf frame * prefix is replaced by tf_prefix 4. In your application launch file / roslaunch command: replace all occurrences of psen_scan with psen_scan_v2

You need further information?

Our international hotline staff will support you individually about our ROS packages at ros@pilz.de

Find more information about the PILZ safety laser scanner on the product website.

Visit us at pilz.com

PILZ is an international-scale, innovative automation technology company. PILZ uses its solutions to create safety for man, machine and the environment. In addition to head office in Ostfildern near Stuttgart, the family business is represented over 2,400 employees at 42 subsidiaries and branches on all continents.

The company’s products include sensor technology, electronic monitoring relays, safety relays, configurable and programmable control systems, automation solutions with motion control, systems for industrial communication as well as visualization solutions and operator terminals.

PILZ solutions can be used in all areas of mechanical engineering, including the packaging and automotive sector, plus the railway technology, press and wind energy sectors. These solutions ensure that baggage handling systems run safely at airports and funiculars or roller coasters travel safely; they also guarantee fire protection and energy supply in buildings.

[sensor_msgs/LaserScan]: http://docs.ros.org/noetic/api/sensor_msgs/html/msg/LaserScan.html [gmapping]: http://wiki.ros.org/gmapping