Application Story

For over 70 years, Detroit Diesel has designed and built the heavyduty engines that fuel commerce and transportation across North America and around the world. The engines power a wide range of heavy-duty vehicles. To ensure the high level of quality and reliability of its engines, Detroit Diesel carries out extensive testing before they go into production. This includes on-vehicle testing on test tracks and public roads. Continuous logging of data from powertrain controllers and subsequent evaluation and analysis of the data plays a vital role in this process.

Challenge: Daimler Trucks North America with its subsidiaries Freightliner and Detroit Diesel used a variety of tools to log data from its engineering vehicle fleets. Due to the lack of having a common data format and ability to log measurements from more than 20 CAN based devices, another tool was needed for recording and displaying data.

Solution: A new tool has been identified and the first migration phase has been successfully completed. The main interest for this Case Study is logging data; other capabilities from the tools described are irrelevant.

Key Benefits: The migration process has been very smooth because all tools are compatible with ASAM A2L files. Without being much aware of it, Daimler Trucks North America is benefiting from ASAM standards by having common data formats and using interchangeable software tools.

Freightliner and Detroit Diesel operate 3 truck fleets:

• Reliability Growth, verify functionality of production intended hardware and software.
• Chassis validation, main focus is hardware and software development related to vehicle systems. In order to calibrate for different environments such as sea level, high altitude, hot ambient and cold ambient, part of this fleet undergoes remote testing during summer and winter.
• Powertrain validation; similar objective as Chassis validation with the exception of focusing on powertrain systems instead of vehicle systems.    

Freightliner and Detroit Diesel need the ability to handle data streams from multiple connected devices and show live data from 100’s of channels, which are displayed on a 50” screen inside a class 8 sleeper cab vehicle.

Vector CANcase XL modules are used as the interface between the CAN bus and data loggers. 

None of the existing tools were able to connect 20+ devices, log data in MF4 format and display live data. A new tool was needed for recording and displaying data. Vector CANape can handle all required task and it is compatible with ASAM *.A2L files. ASAM MCD-2 MC (aka ASAP2) defines a description format for internal ECU variables used for Measurement and Calibration purposes. Any replacement data logger had to be compatible with A2L files because they are also used with MARC I, CSM and CANcase. Most engineers are not aware that the ASAM MCD-2 MC Standard plays a major role in making this a smooth migration. No adjustments have to be made to the existing *.A2L files.

The migration timeline includes a dual phase where both legacy and CANape recorders are simultaneously active. Phase 1: Ramp up Powertrain Validation usage of CANape and keep logging data with MARC I. This dual-phase ensures that no data is lost during any unanticipated problems with CANape. After this short period of time, MARC I logging is stopped. In a similar approach, Phase 2 replaces the CSM loggers at Chassis Validation, which is currently in the dual logging phase. The Reliability Growth fleet continues to work with CANcase loggers who have a similar functionality as CANape without the ability or need to display live data.

It took 1 year of testing and Validation for the implantation at the Powertrain Validation. CANape runs on a rugged dedicated invehicle computer. Due to the high demands on the CPU initially running constantly on 100%, the in-vehicle computers had to be upgraded twice to newer and more powerful models, currently running on the 3rd iteration. In addition, the heavy burden on the CPU was furthermore reduced by limiting the number of simultaneously recording channels at various sampling rates to currently 1073. Many engineers became accustomed to .famos files recorded in MARC I. Since CANape stores data in ASAM MF4 format, some engineers are reluctant to use CANape recordings and still use MARC I on occasion for secondary data logging.

Although running without issues, the Chassis and Powertrain Validation fleets are considered to be a high level user within Vector, testing the upper limits of the system with currently 20+ connected devices.

• Ability to display and record 20+ devices
• Increased program robustness has ensured that very few measurements are lost during recording outside of normal program issues ( operating system crashes, driver initialization error, memory overrun, etc)
• Measurement files are captured in ASAM MF4 format, increasing the number of tools that can process fleet data:
  • In-house data mining tool based on Matlab that was previously only compatible with Reliability Growth and Chassis validation.
  • Automated jBEAM report generator
  • Uniplot, CANape, DIAdem, ASAM ODS, etc.
• CANape allows loggers to be controlled by scripts, eliminating the task of manually triggering logs and coming up with measurement filenames on the fly by having a standardized naming convention
• Added data transparency by having rich, descriptive metadata about Vehicle, configuration and route in each file header by entering information into a custom CANape panel

The migration process is nearly completed. Due to the ever increasing number of devices and Measurement channels, more powerful in-vehicle computers are needed with USB 3.0 interface to accommodate additional data throughput.