Aerospace manufacturing and testing are complicated for many reasons, not the least of which includes heavy amounts of data collection and endurance testing. Sample and production units that will be used in aerospace applications require tests that are intense in the number of signals that are collected and often in the long duration of test applications. Creating real-world analysis scenarios, coupled with the extreme durations, creates tests that often run for multiple days and sometimes weeks, twenty-four hours each day nonstop. Basic scheduling of that type of test can be difficult and a scenario that becomes significantly more challenging if all or part of the test fails somewhere along the way. Certainly, failure of test equipment must be avoided at all costs.
A California-based aerospace manufacturer recognized that they had exposure to this threat. Not only were their tests long, but their main testing configuration was spread through more than five adjacent manufacturing areas, each with its own control island in the form of a fleet of seven aging Allen Bradley SLC PLCs. A successful test required many shifts to complete and saw data passed from one controller to the next during the execution.
The original system served them well for a long time, but they desired flexibility that the current system couldn’t give them as well as disaster-proofing. The manufacturer turned to Pacific Blue Engineering (PBE) to design, program, and turnkey deploy a revised solution.
PBE placed a redundant Rockwell Automation ControlLogix PAC at the heart of the new solution. This single controller absorbs the functions of all the prior SLC PLCs and is configured with a completely redundant, hot standby processor. This controller executes all the system code in a single place, all the while mirroring its program of setpoints and data signals to the backup controller which is connected via a fiber-optic link to the main controller. In the unlikely event of a failure of the main controller, the backup PAC would assume control without missing a beat. Further, the system human-machine interface (HMI) software was also revised and configured to run on redundant software servers. Thus, an added level of redundancy exists now in both the physical control plane and the system software plane.
Each of the prior systems’ input and output (I/O) connection points were reused. The PLC racks where those signals connected to their prior controllers were removed and replaced with a combination of ControlLogix rack based I/O and Point I/O depending on each location’s needs. These new remote racks allowed for easy connection of existing sensors, and the new racks were connected to the main controller via ethernet. This configuration allowed the PBE team to develop and quickly deploy the revised connection system at the time of installation.
The prior system utilized a LabView-based operator interface software package which was replaced with a FactoryTalk View SE main application. Legacy Allen Bradley PanelView units in the field were upgraded to PanelView Plus7 units. The outgoing software performed well for a long time but lacked the flexibility for easy expansion and upgrade. Functionality changes and even simple upgrades to remain current with the computer’s operating system were increasingly challenging. Moreover, the main system LabView HMI wasn’t designed with the old system PanelView units in mind, so the HMI used by the operators in different locations lacked a common look and feel. The PBE team considered all of this and deployed four PanelView Plus7 units near some of the critical equipment in the field and then mirrored that interface into the new overarching FactoryTalk View SE application. Thus, operators see a homogeneous-looking interface whether running the application from the field side equipment or from the main control room.
As is standard procedure for PBE, the client received video-based presentations throughout the HMI development that allowed them to see the new functionality before it arrived. This allowed the client to have input on the fit and feel of screens and speed adoption of the new system since operators had interacted with the system via the remote sessions.
The PBE team performed the project turnkey. This included verification of the existing field wiring and connections in areas where the existing documentation was lacking details. They built the I/O racks, programmed the system controller and HMIs, and then deployed the revised solution at the client’s site. The result was an efficient upgrade to a current control platform which now allows PBE’s client to test their valuable products without concern for issues with the testing equipment.