Created date: May 15h, 2020.

Introduction

Universal Robots has two built-in safety modes that allow for restricted operation: Reduced and Protective Stop mode. These modes either reduce the maximum speed, power, acceleration, etc of the robot, or stop the robot altogether.  Use the Safety Laser Scanner to switch between these modes and ‘Normal’ mode on-the-fly when a person approaches the robot.

Here we describe integrating the Keyence SZ-04M laser scanner. This Tech Note will specifically show how to set up a Protection Zone for a Protective Stop, and a Warning Zone for Reduced mode.

DANGER:

Installing a safety laser scanner involves changing your safety settings.  Before you configure your robot safety settings, a risk assessment must be conducted to guarantee the safety of personnel and equipment around the robot. A risk assessment is an evaluation of all work procedures throughout the robot lifetime, conducted in order to apply correct safety configuration settings (see the User and Service Manuals).

Safety Modes

This document only describes one of the many possible combinations that the UR robot and the Keyence Safety Laser Scanner can implement.  We do not represent or claim that this is an appropriate combination for your implementation.  This document’s combination is:

• Outer Warning Zone - places the robot in Reduced Mode
• Inner Protection Zone - places the robot in Protective Stop
• Automatic reset for both zones - normal operation resumes when the zones are cleared

Prerequisites

• Keyence SZ-04M Safety Laser Scanner (these instructions are similar or identical for the other sensors in the SZ family)
• Communication Cable SZ-PxxPM (where xx is the length in meters: 5, 10, 20, or 30)
• USB Programming Cable OP-86941 (if needed)
• Mounting Bracket OP-869xx (if needed - xx is one of several mounting variants)

Note that the SZ-04M uses a mini USB connector.   This type is becoming less common.  If in doubt, buy the OP-86941.  This cable is also 5 meters long, which is very convenient when testing the zones you have set.

Mounting and installing

Mounting the SZ-04M

Locate and mount the safety laser scanner according to the manufacturer’s instructions and your risk assessment.

Wiring the SZ-04M to the UR Controller

Completely Shut Down the UR robot - Tap the Hamburger menu on the teach pendant and select Shutdown Robot, followed by Power Off.

Using the Keyence cable:

• Connect the Reset (yellow) and +24V (brown) wires to the controller +24 Power
• Connect the 0V (blue) wire to the controller 0V power
• Remove the lower two jumpers (SI0 and SI1) from the Safety I/O Terminal (the far left yellow I/O block, with the gray plastic jumpers)
• Connect the two Safety Outputs (OSSD) (black and white) wires to SI0 and SI1
• Connect the AUX 1 and AUX 2 (orange and orange/black) wires to CI0 and CI1
• Restart the robot controller. The scanner should boot up when the robot reaches the Getting Started Do not turn on the robot power.
• Set the switch on top of the scanner (behind the door) to the B position.

• Navigate to the “3. Others” menu and then Change Password. Use the up/down arrows to switch between lines on the display and the right arrow to select a menu item.
• Change the password from the factory default of 1111 to be the same as the UR Controller safety password.
• Set the switch on the scanner to the A position and connect the scanner to your computer with the Mini USB cable.

Keyence SZ-V04 configuration

• Download and install the Safety Device Configurator software from Keyence.  As of this writing, it could be found by navigating from keyence.com to Downloads > Software > Safety > Safety Laser Scanners > Safety Device Configurator.
• Unzip the downloaded file and run the setup.exe file inside.   This will install five programs.  You only need the SZ Configurator program

• Run the SZ Configurator program.
• On the first popup, select “Create a new configuration file” and click on OK.

• On the second popup, select “SZ-04M” and click on OK.
• The Configuration Software window should look like the below picture.  You can set general information on the first page.

• Configure the Safety 1 settings.
  • Set Start / Restart to Automatic / Automatic
  • Uncheck the EDM(OSSD1/2) Enable and Reference Points Monitoring boxes

• Leave the Safety 2 settings unchanged.

• Set the Non-safety settings.
  • Set AUX1 and AUX2 to “Detection in protection zone”

• Set a Protection Zone and a Warning Zone for the scanner. See Keyence’s User Manual for full instructions.

• Click on the red Protection Zone box at the top to set the Protection Zone (UR’s Protective Stop zone).
• Using the drawing tools below, draw a line segment, rectangle, polygon, circle, sector (wedge), or freehand to create the zone. You can draw multiple shapes, or use the Delete tools to delete portions of those shapes.

• Click on the yellow Warning Zone box (UR’s Reduced Mode zone) and draw that zone.
• Alternatively, you can use the Automatic Drawing tool, and the sensor will automatically create a zone that includes all of the open space up to the current obstacles it sees.  This zone can then be modified with the drawing tools.

• Transfer the settings to the scanner. Use the new password you set to do so.
• Experiment with the Monitoring mode to confirm the settings are correct.
• When you are satisfied the settings are correct, you can unplug the Micro USB cable and close the cover.  Save your settings to a file and close the SZ Configurator.

Configure the UR safety settings

• Confirm the robot is still powered off.
• Navigate to the Safety I/O Setup screen on UR’s teach pendant. From the home screen tap: Program Robot > Installation Tab > Safety (Enter password) > Safety I/O Tab
  • Select Configurable inputs 0 and 1 for Reduced mode

• Reduced mode parameters can be set on Safety - Robot Limits page. Note that you will not be able to alter the reduced mode settings until a set of configurable inputs are set for reduced mode (above).
• Tap Apply.
• Hard restart the Autonomous Motion Module by cycling the power switch.
• Navigate to the ActiNav Installation page and wait for the system to restart.
• Power up the robot. Wait a minute for the safety scanner to reboot.
  • If you get a SAFEGUARD STOP warning on the teach pendant, just wait a moment.

If the Warning Zone is infringed, the robot will enter reduced mode and perform at the reduced mode settings entered in the Safety setup. If the Protection Zone is infringed, the robot will enter a protective stop mode, and if a program is running it will pause. In this setup, the robot will continue automatically when the Protection zone is clear.