Bioreactor Process Plant Powered by NI LabVIEW and NI CompactRIO

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1 Bioreactor Process Plant Powered by NI LabVIEW and NI CompactRIO Segment: Industry Country: Singapore Author(s): Sanka Hettiarachchi, Providev Kevin Kho, Technologies Unlimited Products: NI crio-9075 (Integrated 400 MHz Real-Time Controller and LX25 FPGA) NI 9203 (8-Ch ±20 ma, 200 ks/s, 16-Bit Analog Current Input Module) NI 9217 (4-Channel, 100 Ω RTD, 24-Bit Analog Input Module) NI 9481 (4-Channel Relay [30 VDC (2 A), 60 VDC (1 A), 250 VAC (2 A)]) NI 9422 (8 Ch, 24 V to 60 V, 250 µs, Sinking/Sourcing Digital Input) NI 9265 (4-Channel, 100 ks/s, 16-Bit, 0 to 20 ma Analog Output Module) LabVIEW LabVIEW Real-Time Module LabVIEW FPGA Module LabVIEW Report Generation Toolkit for MS Office Data Dashboard for LabVIEW 2.0 for ios Category: Teaching; Laboratory; Monitoring; Plant Automation; Challenge: To create a full scale bioreactor process plant integrated with tablet PC based monitoring and control to give the students an exposure of plant automation and sensor integration with mobile computing platforms. Solution: By using the versatile NI CompactRIO platform to interface with the actuators and sensors; the NI LabVIEW software framework together with the NI Scan Engine, NI Shared Variables and Data Dashboard for NI LabVIEW, we were able create a fully functioning bioreactor process plant for the students, giving them a hands-on learning approach and a glimpse of the future of process automation. Bringing Industry to the Classroom Giving students a hands-on industrial experience has always been a goal of tertiary education. The closer the experience to the actual industrial application, the better the understanding of the concepts involved and the real world challenges that would be faced one day. The vision of the educators at Nanyang

2 Technological University Chemical Engineering Department was to create a fully functional bioreactor process plant that allows the students to produce yogurt in the lab. The idea was to create the bioreactor plant with four bioreactors, PID controlled water heating and students monitoring and controlling the temperature set points through tablet PCs that display real-time data. By studying the various outputs, the students were to validate the process operations and also determine the heat balance by analyzing the logged process data. The aim was to create an experience as close to the real world as possible. This vision was our challenge during the preliminary discussion conducted by Mr. Kevin Kho, formerly with Nanyang Technological University together with Providev and National Instruments. Our mission was to create a state-of-the-art process plant and tablet PC integrated application to give the students a glimpse of the future. Providev, being a NI Alliance Partner with over eight years of NI LabVIEW development experience, was introduced to the customer by the NI sales team to support development and integration of this project. The requirements were perfectly within reach of the NI CompactRIO platform and NI LabVIEW as the software framework. The newly launched Data Dashboard for NI LabVIEW 2.0 with improved features was a timely release which allowed the realization of tablet connectivity with minimum cross-platform development effort. All this and the strong NI Developer Community support were critical in letting us making this project a success. System Overview The process control plant designed for the laboratory consists of the following sub-systems (Figure 1): 1. Reactors A,B,C and D 2. Return Water Line 3. Cold Water Line 4. Hot Water Line 5. Steam Input

3 Figure 1: Bioreactor process plant system drawing. The sub-systems are monitored and controlled by three NI CompactRIO real-time controllers. Two CompactRIO 9075 controllers share control of the four reactors whereas all the utilities (hot and cold water temperature and water reservoir levels) are controlled by one. All the parameters are monitored in real-time and sent to the Instructor PC through Ethernet and then to the tablet PCs used by the students through Wifi (Figure 2, 3 and 4).

4 Figure 2: System Hardware Connections Overview. (a) Viewing window of the Bioreactor where the students can monitor the contents within. (b) Laboratory workbenches (c) ipads used by the students with the NI LabVIEW Data Dashboard App. Figure 3: Laboratory Setup.

5 Figure 4: NI CompactRIO Assembled in Electrical Cabinet. Meeting Requirements with the Right Tools The following key considerations were made when choosing the controller for monitoring and controlling the parameters of the reactor: a) Run a temperature control loop with RTD sensor feedback and solenoid valve actuators. b) Monitor RTD sensors and 4-20mA sensors; control 4-20mA analog actuators and 230VAC solenoid actuators; read 24V industrial IO and perform frequency measurements. c) Fast development and deployment to complete the project within a tight schedule. d) Easy viewing of the monitored data from the tablet PCs and ability to send certain control signal commands from the tablet PCs to the controllers. e) Small ruggedized form factor given the limited instrumentation cabinet space. f) Fulfill the design requirements with maximum cost savings.

6 During the requirements analysis it was determined that a small form factor NI CompactRIO system would be ideal for the application. The wide range of C Series modules available for NI CompactRIO allowed us to meet all the types of control and measurement signal interfacing. Since the C Series modules contain built-in signal conditioning, the layout and connections of the sensors were simple and neat. The following modules were selected: Module Signal Type Sensor / Actuator Connectivity NI 9203 NI Ch ±20 ma, 200 ks/s, 16-Bit Analog Current Input 4-Channel, 100 Ω RTD, 24-Bit Analog Input Module NI Channel Relay [30 VDC (2 A), 60 VDC (1 A), 250 VAC (2 A)] NI Ch, 24 V to 60 V, 250 µs, Sinking/Sourcing Digital Input NI Channel, 100 ks/s, 16-Bit, 0 to 20 ma Analog Output Module Table 1: CompactRIO module choice and signal connections. Direct connection of ph sensor signals for monitoring Direct connection of all RTD temperature signals that provided the feedback measurement Direct actuation of 230VAC solenoid valves used for water flow control Water level sensor measurement and pulse frequency measurements for flow sensors Actuation of the air actuated valve that controls the heating of the hot water utility tank A 2Hz temperature control loop was sufficient to meet the reactor and hot water temperature control requirements. Therefore it was decided to use the NI Scan Engine Interface to accelerate our development process. The NI Scan Engine Interface provided all the basic functionality and low-level FPGA code for the selected modules. To get the basic IO connections ready for testing, our developers only had to configure the LabVIEW project by inserting the modules and the IO configurations in the NI LabVIEW project. With the use of the NI Scan Interface, we were controlling and monitoring signals without even wiring a single wire of code. Getting a Head-Start with Sample Projects Once the initial system requirements were set and IO connections verified, our next step was to determine the system architecture for our application. The NI LabVIEW in-product sample projects was invaluable during this stage since it gave us a scalable, well documented starting point that perfectly fit our overall system requirements. The "NI LabVIEW Real-Time Control on CompactRIO (RIO Scan Interface) sample project template that was used included extensive documentation that clearly indicated how the code worked and also useful comments for adding and modifying functionality. The sample project wizard in NI LabVIEW finishes by creating a fully functional project inclusive of the Scan Engine Interface for CompactRIO, a real-time application, host PC communications and a sample user interface for a monitoring and control. All code organized neatly in a scalable folder structure. As

7 developers we truly appreciated the efficiency of the built-in system level integration support in NI LabVIEW and knew the choice of development framework truly set us ahead of the pack. With the above project as a starting point the development team went ahead to customize and modify the template project to suit the fine details of the application. At the end of the project, the template was extended to three NI CompactRIO systems and many additional features implemented all on top of the built-in project template. Tablet PC Integration without Cross-Platform Development At commencement of the project there was a vision by the customer to create a next generation learning experience. The ability to monitor, control and interact with the Process Control System through ios or Android tablets were an integral part of this vision. Our confidence in realizing this was only possible due to the Data Dashboard for NI LabVIEW app. Using this free app on ios, our engineers were set to create beautiful learning pages with real-time data updates, all received through the NI Shared Variables from the host PC. By utilizing the web-services support in NI LabVIEW and the Data Dashboard app, we were able to display the monitored data with minimum latency and allow students to enter their address and request the logged data to be sent to their s at the end of each laboratory session. Our effort was further reduced, since the Dashboards created on ios were also fully compatible with Android tablets without any modifications. At project completion, we had ios devices successfully linked to the system without any cross-platform development effort (Figure 5 and 6). The costs incurred for tablet development tools, equipment and specialized app developers would have been easily in the tens of thousands of dollars. The Data Dashboard for NI LabVIEW app resulted in massive savings in time and effort.

8 Figure 5: NI LabVIEW Data Dashboard Screens.

9 Figure 6: NI LabVIEW Data Dashboard Screens. Conclusion The requirements of present day industrial systems are not trivial. To allow present day students to learn and experience the future of industrial systems requires a clear vision and the right tools to realize it. The choice of using National Instruments hardware and software ensures us that we are equipped with the tools that are needed to meet such requirements with maximum efficiency and effectiveness. Author Information: Sanka Ravipriya Hettiarachchi Systems Engineer, Providev sanka@providevintl.com