NI RIO Platform: Embedded Measurement and Control Solution Integrating Real time Processing and FPGA

NI RIO Platform: Embedded Measurement and Control Solution Integrating Real time Processing and FPGA

The demand for high performance, high reliability, and flexible customization is increasing in modern industrial control, structural health monitoring, and embedded testing systems. The RIO (Reconfigure I/O) platform launched by National Instruments (now Emerson's testing and measurement business) integrates Intel or Arm processors, user programmable FPGAs, modular I/O, industrial communication interfaces, and LabVIEW development environment into a unified architecture, providing engineers with powerful embedded solutions. The two main hardware forms of the platform - rugged CompactRIO and compact Single Board RIO (sbRIO) - have been optimized for distributed industrial control and batch OEM embedded applications, respectively. This article will provide a comprehensive and in-depth technical analysis of the NI RIO platform from the perspectives of platform advantages, system architecture, module selection, software development, industrial connectivity, and practical cases.

Core advantages of RIO platform

The design goal of the RIO platform is to provide a powerful and easy-to-use hardware foundation for testing, measuring, and controlling applications. The three core advantages are as follows:

excellent performance

Compared to traditional PLCs or PACs, RIO platforms are capable of handling more challenging real-time tasks. High speed deterministic operation implemented through FPGA, with a control cycle rate exceeding 1 kHz and an I/O sampling rate of up to 1 MS/s per channel. FPGA provides precise timing and control capabilities, allowing complex algorithms to run directly in hardware without being affected by processor load.

Accelerated development process

By using ready-made hardware and a unified software environment (LabVIEW), developers can quickly prototype and easily deploy to different RIO hardware forms without the need for extensive software modifications. Compared to customized hardware design from scratch, this commercial off the shelf (COTS) approach significantly shortens product time to market.

Robust reliability

CompactRIO adopts a cast aluminum shell and a fanless passive heat dissipation design, meeting strict industrial environment specifications: operating temperature of -40 ° C to 70 ° C, able to withstand 50g impact and 5g vibration (RMS). This reduces mechanical design time and ensures long-term reliability in harsh environments.

CompactRIO System Architecture

All CompactRIO hardware consists of three key components: real-time processor, FPGA, and connection to signal converters (typically located in C-series modules).

Real time processor: runs a standard kernel based real-time operating system (NI Linux Real Time or VxWorks) designed for reliable and deterministic operation. The LabVIEW VI on the processor receives module data, network system data, or data from peripheral devices (such as HMI) forwarded by FPGA. Users can host web services, read/write disks, or run deterministic PID loops on the processor.

User programmable FPGA: Using Xilinx's FPGA technology, programming is carried out through LabVIEW FPGA modules. FPGA is directly connected to all onboard I/O and C-series modules, enabling offloading of time critical tasks such as advanced control algorithms, signal processing, filtering, or custom timing logic. The key point is that users can independently decide whether the analysis and control logic occurs on the processor or FPGA according to application requirements, and even achieve closed-loop control that runs entirely within the FPGA without the need for processor intervention, thereby achieving extremely low latency.

C-series I/O modules: Provides over 70 module options for measuring electrical signals, reading and writing digital lines, connecting sensors, or generating output signals. Signal conditioning and analog-to-digital conversion are completed within the module, and digital values are collected by LabVIEW FPGA VI. Engineers can design application specific timing, logic, and synchronization parameters in FPGA VI.

C-series modules: rich I/O options

The C-series module is the I/O front-end for CompactRIO and sbRIO systems, covering a wide range of types from basic voltage and current measurement to professional sensor interfaces. The following are typical module specifications organized according to the document:

Analog input module:

Voltage: Up to 32 channels, optional range from ± 200 mV to ± 800 Vrms, maximum sampling rate of 1 MS/s/ch, supports inter channel isolation and anti aliasing filtering.

Current: Up to 16 channels, ± 20 mA or 0-50 A rms, 200 kS/s, with channel diagnostics.

Universal input: up to 4 channels, supporting voltage, current, thermocouple RTD、 Strain, resistance IEPE，51.2 kS/s/ch， Bridge compensation and anti aliasing filtering.

Thermocouple: Up to 16 channels, supports J/K/T/E/N/B/R/S types, 95 S/s/ch, with cold end compensation.

RTD: Up to 8 channels, 100 Ω or 1000 Ω, 400 S/s, with 50/60 Hz filtering.

Strain/Bridge Path: Up to 8 channels, 1/4, 1/2, full bridge (120 or 350 Ω), 50 kS/s/ch, external excitation.

Sound and vibration: up to 8 channels, ± 5 V or ± 30 V, 102.4 kS/s/ch, IEPE compatible.

Analog output module:

Voltage: Up to 16 channels, ± 10 V or ± 40 V (stacked), 1 MS/s/ch.

Current: up to 8 channels, ± 20 mA, 100 kS/s/ch, with open-loop detection.

Digital I/O module:

Input/Output: Up to 32 channels, TTL (3.3 V/5 V), RS422, 5 V to 240 V AC/DC, minimum pulse width of 55 ns, supporting inter channel isolation, source or drain input, bidirectional channels.

Relay output: up to 8 channels, 60 V DC or 250 Vrms, SPST or SSR.

Communication module:

CAN: 1 or 2 ports, supporting HS/FD, LS/FT, 1 Mb/s.

LIN: 1 port, 20 kb/s.

Serial interface: 4 ports, RS232/RS485/RS422，921.6 kb/s。

GPS timing and synchronization module: Connected to a standard antenna through the SMB interface, it provides accurate GPS time data, which can be used for timestamp, gate control acquisition (based on GPS second pulses), or waveform acquisition of multiple CompactRIO systems distributed over a large area structure. Note that this module is not suitable for mobile applications and needs to be kept stationary.

CompactRIO Controller and Expansion Chassis

The document lists multiple models of CompactRIO controllers, with the main differences being the processor, FPGA size, and number of slots. For example:

CRIO-904x series: Intel Atom dual core or quad core, 1.30-1.60 GHz, 4 or 8 slots.

CRIO-905x series: 1.33 GHz dual core Intel Atom, 4 slots.

NI-914x series: EtherCAT or Ethernet expansion case for distributed I/O, operating temperature range of -40 ° C to 70 ° C.

All controllers support NI Linux Real Time operating system and offer multiple international power cord options (USA, UK, Switzerland, Australia, Europe, Japan, India, Korea, China, Brazil, Taiwan, etc.).

Single Board RIO (sbRIO): Embedded Single Board Controller for OEM

SbRIO is designed specifically for high-capacity OEM embedded control and analysis applications, integrating real-time processors, FPGAs, and I/O on a compact single board. It is part of an accelerated custom design platform that can help customers quickly bring embedded control systems to market. SbRIO is based on the CompactRIO platform, thus inheriting FPGA performance, real-time determinism, and reliability, while having lower non repetitive engineering costs compared to fully customized hardware designs.

The document lists multiple sbRIO models, with the main differences as follows:

Model processor RAM FPGA onboard I/O expansion interface

SbRIO-9603 Intel 1.33 GHz Dual Core 1 GB XC7A75T Digital I/O 2 × C Series, 96 DIO

SbRIO-9609 Intel 1.91 GHz quad core 2 GB XC7A200T only digital I/O 2 × C series, 96 DIO

SbRIO-9628 Intel 1.33 GHz Dual Core 1 GB XC7A100T 16 AI, 4 AO, 110 DIO 2 × C Series

SbRIO-9629 Intel 1.91 GHz Dual Core 2 GB XC7A200T 16 AI, 4 AO, 110 DIO 2 × C Series

SbRIO-9638 Intel 1.33 GHz Dual Core 1 GB XC7A100T 16 AI, 4 AO, 110 DIO 2 × C Series

SbRIO-9651 667 MHz dual core ARM Cortex-A9 512 MB XC7Z020 without onboard I/O 160 DIO, PCIe, SATA

SbRIO supports interfaces such as Time Sensitive Network (TSN), Dual Ethernet, CAN FD, RS-232/485, USB 3.1, and DisplayPort. At the same time, we provide thermal management kits, junction boxes, cable trays, and other accessories for easy integration.

Developing RIO System with LabVIEW

LabVIEW is the core development environment of the NI RIO platform, which abstracts complex underlying tasks in embedded system programming, enabling the design of advanced measurement and control systems without the need for a large development team or extensive experience in hardware description languages.

Unified project management: The main processor VI and FPGA VI are located in the same LabVIEW project for easy development and debugging. FPGA VI and real-time VI can efficiently exchange data through DMA FIFO or Interrupt (IRQ).

Built in library: LabVIEW contains nearly 1000 built-in signal processing, analysis, control, and mathematical functions, accelerating the development of embedded measurement systems.

Remote system management: The built-in system management tool supports remote updates of hundreds of controllers or data transfer between different systems.

Open software interoperability: LabVIEW can call external C code and integrate with Python,. NET, etc., making it easy to reuse existing IPs.

Developing a CompactRIO system typically involves creating an FPGA VI in a LabVIEW project to implement high-speed I/O and timing logic, creating a real-time VI to implement the main control loop, network communication, and data recording, and then compiling and deploying it to the target hardware. The graphical programming approach of LabVIEW makes FPGA development intuitive, without the need to learn VHDL/Verilog.

Industrial connectivity and environmental adaptability

CompactRIO supports multiple industrial communication protocols and can serve as an IIoT gateway to translate between different protocols. The supported protocols include:

EtherNet/IP

Modbus (Serial and TCP)

OPC UA

RS-232 / RS-485

MQTT

EtherCAT

CAN bus

DNP3

For harsh environments, CompactRIO has extensive international safety certifications, hazardous location certifications, and environmental certifications. Its working temperature range is wide from -40 ° C to 70 ° C, with high levels of shock and vibration, redundant power input, suitable for scenarios such as oil and gas, factory automation, etc.

Practical application cases

The document provides multiple successful cases based on the RIO platform, demonstrating its value in different fields:

State based monitoring: A utility company has partnered with MSO Technologies and Cyth Systems to deploy a circuit breaker health monitoring solution using sbRIO and LabVIEW FPGA. This proactive maintenance system is expected to save over $400 million within 20 years, extending circuit breaker life, reducing power outages, and improving regulatory compliance through continuous data analysis and automatic event analysis.

Robotic Microsurgery: Medical Microinstruments rapidly developed the Symani surgical system using CompactRIO and LabVIEW, obtaining global regulatory approval in just four years and completing over 1500 surgeries. It was named one of the best inventions of 2024 by Time magazine.

Upgrade of power plant monitoring: A large power plant in Sweden has replaced its aging system with a WireFlow Lunddy data logger based on CompactRIO and CompactDAQ, supporting thousands of I/O channels, high sampling rates, and autonomous offline recording, ensuring long-term reliability and scalability.

Bridge structure health monitoring: COCO Highway Consultants used CompactRIO and LabVIEW to establish a distributed signal acquisition system for Xiamen Jimei Bridge (10 kilometers), monitoring loads, wind, temperature and humidity, and structural dynamics. The University of Exeter has achieved sub microsecond level synchronous environmental vibration measurement on the Jiangyin Yangtze River Bridge using CompactRIO.

Embedded testing system: Thales UK has developed a CompactRIO based virtual test train (VTT) for the London Underground, replacing traditional manual testing and achieving efficient bidirectional testing. Siemens has identified the root cause of voltage transient faults in light rail vehicles using CompactRIO, significantly reducing faults and operational delays.

Hardware Services and Support

NI provides a standard one-year warranty for all hardware, including basic repair coverage and factory calibration. In addition, higher-level service plans are also provided:

Standard Service Plan (3 years): Includes comprehensive maintenance coverage, technical support, and factory specification adjustments after each repair. The maintenance turnover time commitment is less than 10 working days.

Advanced Service Plan (3 years): Add system configuration, assembly and testing, advanced replacement (shipped within 1 business day), and system RMA (whole system repair) on top of the standard.

Calibration Plan: Optional standard (<10 working days) or expedited (<3 working days) calibration service.

In addition, a Premium Plus service plan is also available, which allows for customized on-site calibration, spare parts management, and lifecycle services.