Created date: June 9th, 2020.

Introduction

Universal Robots has two built-in safety modes that allow for restricted operation: Reduced mode 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 OS32C laser scanner. This article will specifically show how to set up a Safety Zone for robot protective stop, and a single Warning Zone for robot reduced mode.

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 UR Hardware Installation Manual).

Safety Modes

This document only describes one of the many possible combinations that the UR robot and the 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:

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

Prerequisites

• OS32C Safety Laser Scanner
• 10 Meter Communication Cable (included with laser kit)
• 5 Meter Programming Cable (included with laser kit)
• Mounting Bracket / Protective Cover

Mounting and installing

Wiring the OS32C 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.

• Connect the 24 V (white) of the OS32C to the PWR terminal (red) of the UR controller.

• Connect the 0 V (brown) and External Device Monitoring (brown/white) connections of the OS32C into the GND terminal (black) of the UR controller.
• 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)
• onnect the two Safety Outputs of the OS32C to SI0 and SI1 (red and yellow wires in the image below)

• Now use the Configurable Input connector (CI0 – CI3) and connect the Warning and Auxiliary Outputs (blue and orange/black wires in the image above) of the OS32C 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.

OS32C configuration

OS32C Configuration Tool Software Installation

1. Download OS32C Configuration Tool Software from the manufacturers website:

Scroll down to select Downloads and then open the software section.

Download “OS32C Configuration Tool Version X.X.X”. The Xs representing the most recent software release.

Either launch the CD or the downloaded file to begin the installer.

Run the OS32C Configuration Tool Software

• Upon initial connection, the Configuration Software window should look like the below picture (Refer to user manual for detailed instructions on how to connect PC to configuration software)

• In this note, we will configure one Safety Zone and Warning Zone 1. We will ignore Warning Zone 2.
• In the upper left of the configuration software window, select “Configuration > Edit Zone.” Now select the Safety Zone as the foreground selection.

• The Safety Zone is now highlighted and has “click and drag” circle elements (see picture above.
• Sculpt the Safety Zone into the desired size and shape for the application.
• Repeat the above steps for Warning Zone 1 (see pictures above for reference).
• In this example, the Safety Zone is set up as a half circle with a radius of 1 meter and Warning Zone 1 is a half-circle with radius 2 meters.

Note: The lines with green and red dots show a snapshot of what the scanner “sees” in its environment.  To actively monitor, select “Utilities -> System Monitoring” to get an idea of the surroundings and what the size of the zones should be.

• The section on the right of the configuration window shows the safety parameters, along with non-safety parameters that dictate the behavior of the OS32C
• View the picture below for the parameter settings:

• Note that the “Operating Mode” is set to “Automatic Start.” This will ensure that the scanner begins monitoring the zones and performing as programmed upon power up of the system.
• In the Non Safety-Critical Parameters, the Auxiliary output and the Warning output are of special interest for this setup. Ensure that the following are set correctly:
  • Auxiliary output mode: Warning zone 1 infringed
  • Auxiliary output type: PNP
  • Auxiliary output polarity: Active OFF
  • Warning output mode: Warning zone 1 infringed
  • Warning output type: PNP
  • Warning output polarity: Active OFF
• The above selections will ensure that when an object or person enters the warning zone the robot will enter reduced mode.
• Save the configuration and select “Configuration -> Sent to sensor/Enter CFG mode -> Entire Configuration.
• Confirm all settings and select “Yes” to register changes. The scanner will reboot and the configuration will now be active.

Configure the UR safety settings

• 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 Safety 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 Safety zone is clear.