Car manufacturers perform suspension tests on shocks, chassis acceleration measurements, stability and traction control analysis, automatic brake system (ABS) testing and more to make sure they provide a safe car for consumers.
Traditionally, all of these tests require multiple pieces of test equipment. According to the company, the National Instruments CompactRIO system introduces a rugged, high-performance system that leverages field-programmable gate array (FPGA) technology that allows engineers to customise a single hardware platform to solve a variety of in-vehicle applications, including vehicle dynamics and more.
Build custom hardware quickly with FPGAs
An FPGA is a chip that contains reconfigurable gate array logic circuitry and is at the centre of the CompactRIO architecture. Engineers can program and reconfigure FPGA hardware via software, giving them the ability to create different custom test hardware quickly.
Unlike processors, FPGAs use dedicated hardware for processing logic and do not have an operating system. Some of the many advantages the FPGA offers are custom I/O timing and synchronisation, 20 MHz control loop rates, the reliability of dedicated hardware and digital signal processing and analysis, the company said.
Graphical FPGA programming
Traditionally, engineers needed extensive knowledge of hardware design tools and languages such as VHDL to program FPGAs.
Today, test engineers can use graphical development tools, such as National Instruments LabVIEW, to customise and reconfigure FPGAs in less time. When their system functionality needs change, developers simply make changes to their graphical code and simply download the new code to the FPGA to change the custom hardware within their test system.
Custom timing and processing of I/O
CompactRIO has a variety of industrial analogue and digital I/O modules that contain signal conditioning, conversion circuitry and isolation for any sensor type. Because the FPGA is connected directly to each I/O module, engineers can customise the sampling rates of CompactRIO on a per module basis providing unmatched timing flexibility for the system.
Engineers can configure CompactRIO to take 200 Hz chassis acceleration measurements and then reprogram the system in minutes to solve the needs of high-speed brake noise and acoustic measurements. Additionally, engineers can configure the FPGA within CompactRIO to perform low and high speed measurements simultaneously within the same system to perform different vehicle dynamic tests in parallel. Test engineers can also use the FPGA to easily synchronise CAN bus data with other analogue or digital I/O signals as well as perform digital signal processing on any sensor reading (anti-aliasing filtering, FFTs, frequency windowing, and more), the company said.
Small, rugged package for any in-vehicle nvironment
The mechanical design of CompactRIO creates a system that can withstand the rigors of any in-vehicle testing environment. A four-slot reconfigurable embedded system measures 179.6 by 88.1 by 88.1 mm (7.07 by 3.47 by 3.47 in.) and weighs just 1.58 kg (3.47 lb). An eight-slot system filled with 32-channel I/O modules delivers up to 256 I/O channels per system.
• -40 to 70 °C (-40 to 158 °F) operating temperature
• Up to 2,300 Vrms isolation (withstand)
• 50 g shock rating
• International safety, EMC, and environmental certifications
• Class I, Division 2 rating for hazardous locations
• Dual 9 to 35 VDC supply inputs (6 to 35 VDC during operation)
• Low power consumption (7 to 10 W typical)
Conclusion
According to National Instruments, CompactRIO combines the flexibility of FPGA technology and the ease-of-use of LabVIEW graphical programming tools to create a solution for any vehicle dynamics test.
The high speed and synchronisation capabilities of the FPGA, combined with a rugged form factor, and a wide range of I/O modules create a platform that automotive engineers can standardise on to solve a variety of vehicle dynamic test applications.