Posts

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

Related Links