Introduction

This tech note describes how to integrate a stack light with an ActiNav program.  In this example, the stack light signals green for a running program, amber for a program that is running below a set performance level (such as when the parts bin needs refilling), and red for a stopped program.

Prerequisites

• Multi-color Stack-light LED, such as (https://www.mcmaster.com/1577t43)

• Useful link:  https://www.mcmaster.com/machine-lights

Wiring

The stack light used here comes with 6 wire leads. We will only use 4 (Yellow for ground, red for red color LED, orange for amber color LED, green for green color LED)

Connect the leads to Digital I/O ports on UR controller as shown

Program

1. Logic:
• Green color: Program running as expected
• Red color: Program Stopped
• Amber color: Needs assistance (Either 3 count running average cycle time falls below pre-set value or the present cycle is taking longer than another pre-set value)
2. Feel free to modify the program below to suit your needs.
   • Set default (start) values for I/O

Initialize variables for the program as shown

Program template is as follows:

Add Before Start Sequence to your program as shown (Initialize variables)

Add the following lines to your Robot Program node.

These lines calculate average cycle time for the last 3 counts using three timer variables (t1, t2, t3). The light will turn Amber when the average exceeds 15 seconds

Add a parallel thread containing additional logic for switching between light colors. This also contains a separate one count timer (timer_2) that monitors the current cycle’s execution time.  When the cycle time exceeds 60 seconds, the light is changed to Amber.

Disclaimer

This article was written using a system with a prototype version of ActiNav

Test the program to make sure it works as intended