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Collect Vehicle CAN Bus data with NI 9862 and iTestSystem

Automotive and off-highway engineers and designers often need to log vehicle bus data along with vibration, strain gauge, and other sensor data during normal operation to evaluate their design.  Using data from all these sources enables these engineers and designers to pinpoint a vehicle’s response to staged or damaging events.  For example, engineers can see how steering wheel position and speed effect structural response when the vehicle hits a pothole.

How does steering wheel position and speed effect structural response when the vehicle hits a pothole?

In situations where our engineers need to tap into the vehicle’s on-board diagnostics using CAN bus data and analog sensor data to identify and solve a problem, we will deploy a rugged measurement solution based on NI CompactDAQ (cDAQ) hardware.  These systems usually include an industrial compact pc or standalone cDAQ running the iTestSystem engineering measurement application.  iTestSystem logs data from the vehicle bus connected to NI 9862 CAN module and other analog sensors connected to NI cDAQ modules like NI 9234, NI 9236, and NI 9229 into one data file.

NI 9862 CAN Module Specifications and Connections

According to the NI data sheet, the NI 9862 modules is a single CAN port device that is isolated from the other modules in the system. The port has a Bosch DCAN CAN controller that is CAN 2.0B-compatible and fully supports both 11-bit and 29-bit identifiers. The port also has an NXP TJA1041AT High-Speed CAN transceiver that is fully compatible with the ISO 11898 standard and supports baud rates up to 1 Mbps.  This module requires +9 to +30 VDC supply voltage to operate.

The table below shows the connections between the NI 9862 9 pin D-Sub and the SAE J1962 connector that are required for CAN communication.  NI sells a OBDII9M-DB9F CAN Cable cable if you don’t want make your own cable.

iTestSystem CAN Channel Setup

Setting up a vehicle CAN bus connection can be difficult, especially if you need to acquire non-standard, proprietary messages and frames.  iTestSystem simplifies this setup by leveraging the NI XNET and CAN drivers to view and configure CAN bus data, import databases, and assign scale factors. iTestSystem then allows users to browse and choose which CAN signals to acquire.

For more information about collecting CAN bus data with an NI 9862 and iTestSystem, or our testing services, contact Chase Petzinger via email at chase.petzinger@itestsystem.com or phone at (844) 837-8797 x704

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Engineering on the fringe of big data

As test engineers, we are driven by data. It motivates everything we do. The faster we can gather, manage and analyze vast amounts of data, the more effective and efficient we become at understanding the stresses that tax modern machinery.

That is why I’m excited to share some of the recent advances Integrated Test & Measurement (ITM) has made as it relates to our large channel synchronized count monitoring systems.

In many ways, we are hitting the extreme fringes in terms of gathering big data, and these developments have all been made possible by our proprietary iTestSystem software.

(Download a free version of our base software.)

Test Engineering Extremes using iTestSystem and NI cDAQ

  • Collecting and managing terabytes of data during month’s long test
  • Synchronizing 25 NI 9188 cDAQ chassis to collect more than a thousand (1000) channels of strain, acceleration, temperature, voltage and current data
  • Gathering data from on-board systems such as CAN, CCP and customized machine PLC protocols in the same data file as analog data
  • Collecting high voltage and contact temperature data using isolated amplifiers at one megahertz (1MHz)

Train_500Driven by the opportunity to engineer tests for both the rail industry and heavy machinery manufacturers, our team has been able to collect, manage and monitor terabytes of synchronized data during month’s long tests.

The process includes designing and installing data acquisition (DAQ) systems to gather more than a thousand channels of strain, acceleration, temperature, voltage and current data — all at once. Where before we had gathered a couple hundred channels of synced data, we’ve now passed the thousand-count mark. (Incidentally, the manufacturer of our cDAQ hardware platform informed us that our high-channel-count tests are more than double any other application of which they are aware.)

Beyond the volume of channels, we’ve also been able to harvest data from high voltage sources at extreme data rates. One of our colleagues even used iTestSystem to collect 16 channels of data from high voltage sources at 500kHz.

In addition, our engineers have been able to run these tests while at the same time gathering data from on-board systems such as CAN, CCP and customized machine PLC protocols — an advance that allows our clients to gain an even more complete picture of the precise environment at work in their machinery.