Developing a Testing Approach for Robotic Automation - RFID Journal

Developing a Testing Approach for Robotic Automation Nikhil Padhi

Abstract Robotic automation has become “ubiquitous” over the past decade. It has strong potential to reduce costs and improve productivity in plants. Many Factories are embarking on the Robotic automation journey. During the implementation of Robotic automation project, sometimes testing gets “lost” while planning the execution. This article tries to highlight key aspects of test planning during a Robotic automation project.

Introduction: Industrial Automation is at the heart of productivity and traceability improvements in factories. Robots have been an essential part of automation for decades, however, they became mainstream during the last decade. Plants across the world have started embracing robots which has helped the Robot family grow many fold. Today, there are standard robots for many operations across industry verticals. On top of this, Robot manufacturers can build a custom robot for virtually any operation. Installing a robot in a plant is as much important as manufacturing a Robot. Testing during installation is an important step. This paper tries to outline key aspects of testing during installation of Robots.

Defining the Scope of Robotic Automation: Robotic automation refers to automating one or multiple operation step(s) in a production line. Robotic Automation is different from Robotic Process Automation (RPA). Robotic Automation refers to automation on the shop floor while Robotic Process Automation refers to automating a business process such as processing a customer invoice or processing a customer request through an IVR (Interactive Voice Recorder). System scope includes automated interaction of Robots with PLC (Programmed Logic Control) and with the shop floor systems, MES (Manufacturing Execution System) & SPC (Statistical Process Control). This interaction results in execution of process step by the Robot, automated transaction processing in MES & PLC and progression of WIP (Work in Process) to the next step.

Differentiating Robotic Automation testing: The next question that we need to answer is, how is industrial automation testing different? Unlike software testing, Robotic testing involves equipments, Robots and material flow. Let’s get into a little more detail. A typical test cycle will involve production of a sample lot using real equipments, Robots and actual raw materials. During the production of this sample lot, we will test if the equipments & robots are communicating correctly with the shop floor systems (MES & SPC) and if correct transactions are automatically logged in them.

Robotic Testing 

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It involves Systems, Equipments, Robots and Communication Layer between System-Equipments & Robots-Equipments and RobotsSystems Scope includes Functionality Testing of Systems , Equipment Controls (PLC) & Robots Scope of interface testing includes system to system as well as equipments to system and robots to system and robots to equipments Physical Flow/Material Flow is an integral part of testing Development as well as bug fix by multiple vendors; Software product vendor, System Integrator , Equipment Vendor & Robot vendor Simulation plays an important role

Traditional Software Development Testing    Vs

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It primarily involves systems and interfaces between systems It involves functionality testing of Systems Scope of interface testing includes system to system testing Physical Flow/ Material Flow normally not part of testing Development as well as bug fix by Software product vendor, and System Integrator Limited role of simulation

Developing Test Strategy for Robotic Automation Testing: How do you develop a strategy for testing industrial automation solutions? On the surface of it, it looks complex, however if you follow a step a by step approach, it shouldn’t be too tough. Let’s try and understand some key steps. Create an overall Approach: Create an approach which has details like teams to be involved, high level scenarios, dependencies such as equipment readiness, usage of simulation for testing during development when equipments are not ready etc. Formation of cross-functional team: First, identify all the teams who need to be involved during testing. It will normally consist of Super Users from Manufacturing Operations, Planning, Warehouse, Engineering,

Quality, IT & Accounting. This will allow us to test end to end test cycle; release a work order, execute the work order, ship the lot produced and validate accounting entries. Sometimes, we overlook the role of accounting. They need to make sure Finished Goods and Work in Process (WIP) are hitting the corrects accounts. Quality team test rework, scrap and defect logging. Creation of Test Scenarios and Test Cases: Divide the test scenarios into multiple buckets. For example, ERP testing (Enterprise Resource Planning) should include Demand Planning, Work Order Management, Accounting Validation etc. MES (Manufacturing Execution) testing should include production planning, Work Order execution, execution of process steps to be performed by the Robots as well as by the operators. There should be scenarios to test multiple integrations, Robots-PLC (Programmed Logic Control), PLC-MES, Robots-MES (if required) & MES-ERP. Execution of Test Scenarios: You should plan to perform Unit test during Development through simulation. Essentially, machine movement need to be simulated. During UAT (User acceptance Test), testing will be done with actual equipments. Tracking test results and Defects: We should use a tool such as JIRA as the repository for test scenarios and to track testing progress. Obtaining the Sign off: At the end of UAT, get the sign off from all functional groups involved; Manufacturing Operations, Planning, Warehouse, Engineering, Quality, IT & Accounting will provide their sign off. Accounting Sign off required to warp up testing phase.

Managing Risks: Lead time associated with Robots & Equipments: There might be times when the lead time to fix a bug in Robots or in Equipments is longer. UAT (User Acceptance Test), should factor in this lead time. Shorter UAT duration: Time available to perform the UAT or FAT is relatively less. This is because, UAT can be performed only after the Robots and other equipments are installed. Once the equipments are installed, production needs to start “immediately”. Hence, lot of prep work in terms of simulation and other setups must be done before the UAT starts. UAT Execution for existing production Lines: Doing UAT in existing lines can be tricky. As the operations are already on, we need down time (DT). Hence, the timing of the UAT is important. Ideally it should be planned during planned shut downs such as yearend shut down. Managing Super Users: Considering the involvement of multiple teams, test planning must be done well in advance to block the schedule of key users. A few things to keep in mind is tight cross-functional collaboration, constructive collaboration with multiple vendors such as Equipments & System Integration (SI) vendors, detailed planning and inclusion of diverse test scenarios hold the key to success of testing phase.

Conclusion:

Robotic Automation is a significant initiative to drive up productivity. It has the potential to drive down costs which will in turn help improve profitability. Testing the Robots during commissioning is as much important as designing the Robots. At the end of the day, Robots, post installation should hit target Yield and OEE (Overall Equipment Efficiency). Testing phase can provide insights into Robot’s performance post deployment; hence organizations need to invest significant amount of time and effort in testing. It will make sure there is a good and hassle-free beginning to “Robotic” journey.