Monday, April 19, 2021 · 16 min read
Road Load Data Acquisition and Vehicle Durability Testing in Extreme Environment
A large manufacturer in the automotive industry searched for a new system to acquire road load data and test vehicles' durability in extreme environments. A simple, rugged, and dust-proof system with native CAN FD and Kistler’s KiRoad support - that’s Dewesoft.
When you need to test full vehicle durability and safety, road load data acquisition is the way to go. It supplies data on the vehicle’s response to the road, the loads that the vehicle will undergo during its lifetime. This implies collecting information about the road characteristics and many other driving and vehicle parameters. Road load data acquisition usually requires a large number of input channels.
In this case, the customer is a large automotive manufacturer who is present in the automotive industry for almost a century. With their iconic designs, high-end technology, and extremely efficient production, they are nowadays known all over the world. Vehicle development, testing, and manufacturing are closely related in their business, so every equipment optimization is really important for them as it allows to speed up the production or the development process.
Vehicle durability measurements are done during test drives or on testbeds. Tests are done either for an entire vehicle, a subsystem, or certain components. Road load data measurements are collecting information about the road characteristics and many other driving and vehicle parameters such as vehicle velocity, air, and rolling resistance, engine loads, inertia, mass, and many more.
Existing customer issues
The engineers in the testing department were working with an older road load data acquisition system to acquire data from the road and test their vehicles in various environments all over the world.
Their main drive to exchange the old system was to have just a single unit for data acquisition, dust-proof, rugged and also supporting standards that have emerged in recent years like CAN FD and Kistler’s KiRoad Performance wheels. Additional requirements were to support the automated setup of the measurement based on the export of an existing database and the possibility to use the system on testbeds via EtherCAT.
One DAQ device for all input channels
Having a single simple unit that can handle many analog and digital inputs was the first requirement that our customer had. Cabling and compact sizing of data acquisition systems are important for them when it comes to connecting, mounting, and transferring data acquisition units from one place to another.
The road load data acquisition systems also need to be powered from the car's battery power supply thus having a low power consumption DAQ system is very important. Also having power redundancy with the DAQ system’s built-in backup batteries is very important and brings additional measurement security.
Rugged, dustproof, and flexible
Another big issue for the customer was their non-dust-proof units and their connectors. They are testing their vehicles all over the world. The desert testing environment in Nevada, USA is their main concern. Besides the sand that can ruin the unit’s amplifiers, Nevada’s high temperatures are really problematic for DAQ systems if the cooling is not properly solved.
CAN FD acquisition support
Many older systems nowadays lack CAN FD support, which has become a standard in modern high-performance vehicles. To have all the information from the modern vehicle, the CAN FD data protocol needs to be supported and integrated with the whole DAQ system and used software.
Dewesoft provides a synchronous CAN bus and CAN FD acquisition on their DAQ devices with full software support for visualization and analysis of the acquired CAN bus data.
Kistler KiRoad performance support
The Kistler Group is a market leader for dynamic pressure, force, torque, and acceleration measurement technology, and one of the biggest manufacturers of wheel sensors used exactly for road load data measurement.
To efficiently acquire data from these sensors – and keep them synchronized - support for their systems is indispensable. Not having KiRoad support was crucial for our customers to exchange the old DAQ system for a new one.
Customer’s specific database support
The customer stores their channel and measurement setups in their specific database. The old DAQ system had automated the creation of the sensor database and setup. This functionality should be continued which means the new data acquisition software needed to support the import format of this external database. Simplifying and automatizing this process would be beneficial for them - they would save a lot of time and avoid manual input adjustment mistakes.
Dewesoft road load data acquisition system
Late in the year 2020, Dewesoft replaced the existing customer’s system with the new, optimized system, which was completely synchronized and compatible with the customer’s vehicles that used CAN FD and Kistler KiRoad sensors.
The road load data acquisition (RLDA) system delivered to the customer was designed for durability testing methods and road load data analysis of three vehicles. The system included about 200 channels per car, and it was intended to be easily mounted and connected and work in extreme environments. Therefore, the system needed to be optimized in size and cooling.
The new system delivered by Dewesoft included 8 units of R4rt DAQ devices and 3 units of R2rt DAQ devices. With these, the customer can measure the following parameters on three vehicles:
Wheel force transducers (WFT)
Resistance temperature detectors (RTD)
R4rt units are compact, high-quality data acquisition systems that can handle up to:
64 analog inputs
32 counter inputs
96 digital channels
32 analog outputs
The systems also feature a built-in high-performance and highly reliable data processing computer and SSD data logger.
Such device flexibility enables connecting multiple channels to a single unit. All R4 and R2 devices are completely dust-proof and have optimized cooling so they can be used in any extreme conditions. Sensors connected on SIRIUS R(x) units are as well connected over dust-proof LEMO connectors.
To cover the CAN-FD measurement, Dewesoft supplied the customer with 4 additional KRYPTONi-1xCAN-FD devices.
KRYPTON devices are rugged and distributed EtherCAT data acquisition devices for field measurement in extreme and harsh environments. The KRYPTON DAQ systems offer an IP67 degree of protection - high shock protection and operation in temperatures ranging from -40 to +85°C.
KRYPTONi-1xCAN-FD has a single CAN FD port and using the EtherCAT data interface several devices can be daisy-chained with a single cable for power, data, and synchronization. This allows the customer to position the CAN FD connection in the car next to the bus to reduce the cable length of CAN FD.
The full hardware and software support of Kistler’s KiRoad Performance system offered by Dewesoft satisfied the customer's needs. All acquired channels can be meaningfully grouped, and all the input channels and amplifiers information can be imported into the DewesoftX software from the customer’s specific database, which completely automatizes the measurement setup process.
To prepare the system for possible future system integration with a testbed, Dewesoft added a single digital real-time EtherCAT channel output. This addition can feed real-time data to the testbed to a 3rd party control system (like MTS FlexTest) and record full-speed data to DewesoftX software in parallel.
Such a decision can reduce the customer’s setup costs vastly as the solution requires only a single cable from Dewesoft’s DAQ systems to the test bench controller. It also eliminates the need for a high-level analog input stage on the controller side and eliminates kilometers of cabling.
During the outdoor road test and measurement, all of the DAQ hardware is mounted on the back seats of the tested vehicle. For the single vehicle, the R4rt DAQ system is used as the base system of the whole configuration that has connected a display and a keyboard for the test-driver.
The R4 is a compact data acquisition system built around SIRIUS DAQ technology. Systems feature DualCoreADC® analog inputs with 160 dB dynamic range and acquisition speeds of 200 kHz per channel or optional high-speed amplifiers with speeds up to 1 MHz per channel.
As mentioned above SIRIUS R4 chassis can hold up to 4 SIRIUS DAQ slices with up to 64 analog inputs, 32 counter inputs, and 32 analog outputs with a built-in high-performance data processing computer and SSD data logger.
Other hardware devices such as R4rt-HUB, R2rt-HUB, KRYPTONi-8xTH, KRYPTONi-8xRTD, and KRYPTON-1xCAN-FD extensions are added and connected around the base system.
Every single device was properly synced with the whole system, in which the Kistler KiRoad DAQ unit was used as a master clock for the Dewesoft DAQ system.
DewesoftX software is used to acquire the data from all of Dewesoft’s data acquisition units and Dewesoft’s KiRoad plugin is added to DewesoftX to collect the information from the Kistler sensors and units.
The KiRoad plugin is integrated directly into the DewesoftX and synchronizes all available data from the wheel force transducer system to the Dewesoft analog and GPS data acquisition devices. Channels from these devices will be available in the software as any other channel and can be stored or used directly for further analysis.
Hardware used for a single vehicle
1x SIRIUS R4rt base system
1x DS-DISPLAY 12’ and a Keyboard
Kistler KiRoad and wheel force transducers (WFT) - used as a master clock for Dewesoft DAQ
XCP / CCP
Third-party and related parts
Strain gage sensors
Resistance temperature detectors (RTDs)
Kistler KiRoad Performance torque wheels
With the new Dewesoft DAQ system, the customer gained CAN FD acquisition and native support for the KiRoad Performance torque wheels. They are now able to do the measurement and data analysis on the same system setup.
Such systems can even be extended to thousands of input channels and are capable of recording analog, the digital, counter, video, GPS, and many other data sources, all inside a single box with proper synchronization.
The delivered systems are designed in a rugged and dust-proof fashion with optimized cooling - the customer can use them under any conditions. At the same time, the system is easy to install, and configure, and is immediately ready to run when the sensors are mounted. The customer can export their custom channel setup data from their specific database and import it into the DewesoftX software without needing to manually adjust amplifiers or input channels.
The hardware units are also prepared for testbed integration and real-time control over a single digital EtherCAT channel that the customer may well use in the future.
The same solution is not only suited for automotive vehicles but can be applied in the aerospace and marine industries that need road load data analysis.