To ensure comfort and safety, the automobile industry needs proper T&M instruments.
Automobile manufacturers must ensure customer comfort, well-being and safety. It cannot do that without proper test and measurement (T&M) instruments. Internal processes need to be extremely precise and controlled, because even a minor error can have adverse consequences.
Testing is the process by which automotive companies ensure quality, safety and reliability of automotive systems. This challenge is exponentially getting difficult, as the vehicles can now drive themselves.
To ensure that autonomous vehicles are safer than human drivers, these need extensive testing to help with the design of vehicle components and to validate that the hardware and software perform correctly to increase test coverage, while reducing the cost of tests.
With modular and flexible tools, you can future-proof the systems and adapt to new technologies.
Testing power consumption
A multi-channel power probe determines the power consumption of electronic control units (ECUs) in both standby and wake-up modes. It reads voltage and current, and sends data to the oscilloscope, where it is synchronised with digital bus signals and displayed.
It is possible to measure very small quiescent currents in µA or nA range, as well as high current peaks up to ampere range. With 1MHz bandwidth and 5Msample/s sampling rate, the power probe can even acquire very short current or voltage pulses.
Pavan Kumar, area manager – product support and applications, Rohde-Schwarz (R&S), says, “RT-ZVC probe can be used to add up to 16 additional test channels to RTE or RTO oscilloscopes. R&S offers test solutions for automotive Ethernet that are both comprehensive and compact. RTO oscilloscopes for 100Base-T1/BroadR-Reach allow transmission rates up to 1Gbps.”
Testing infotainment systems
An infotainment system delivers entertainment and informational content. Kumar says, “We provide solutions for testing of infotainment systems, like advanced driver assistance system (ADAS), car audio, vehicle-to-everything (V2X), navigation, protocol decoding and eCall.
“An ADAS wide-band chirp signal generation and analysis can be done using SMW200A and FSW up to 85GHz. 24GHz and 77GHz radars of 2Ghz bandwidth can be easily tested with the test setup.
“A radio frequency (RF) vector signal generator with various radio standards is used for audio-testing AM, FM, DAB, DRM, DRM+, SXM and so on. It is also used for signal generation for GPS, GLONASS, Galileo, Beidou and QZSS. WLAN standard IEEE 802.11p (11p, pWLAN) specifies a technology for V2X communications. We offer several development, certification and coexistence tests for the same.”
A vehicle radar test system is a pre-configured collection of National Instruments (NI) products and intellectual properties specifically designed for testing radar technology in 76GHz – 81GHZ range, from validation through high-volume production. It covers individual radar sensors all the way to integrated ADASes.
One key advantage of a vehicle radar test system is its ability to provide dynamic obstacle generation and comprehensive RF characteristic measurements on top of standard simulators that only work for functional behavioural tests. NI provides solutions to test ADAS, V2X, infotainment, powertrain, and hardware and software as a fully integrated system.
Testing wireless devices
Broadcast technologies keep car occupants connected and entertained. Today, the vehicle incorporates digital radio and video broadcasting. Madhukar Tripathi, head – marcom and optical business, Anritsu India Pvt Ltd, says, “Anritsu automotive test solutions validate the operation of connected car communication systems. These allow tests at all stages of product development, from R&D to production, to provide dedicated solutions and universal wireless testers. This ensures that the products comply with latest industry specifications.
“Anritsu also provides test solutions for electromagnetic interference (EMI), wireless connectivity in vehicle networks, safety and driver aids, and intelligent transport systems.”
Rajesh Gupta, general manager, TUV Rheinland India Pvt Ltd, says, “Our test facilities support complete electromagnetic compatibility (EMC) and wireless testing, according to Automatic Identification System (AIS) requirements, and European and other international standards. These also take care of original equipment manufacturer (OEM)-specific requirements, such as immunity testing up to 200V/m using strip line test method.
“Our expansion plan includes whole vehicle EMC testing with dynamo, complete OEM-specific requirements including electrical, reliability, wireless antenna performance and cellular technology-related testing services.”
Testing environmental conditions
Velocity of air used during painting is extremely critical and should be maintained at a speed of 1m/s to 1.5m/s. CO2 levels in the paint shop must be measured to ensure healthy working conditions. Air coming from the compressor house to the paint shop must be clean, dry and moisture-less. Dew that may seep in the air must be monitored before use. Else, it can directly hamper paint quality.
As per international studies, maximum 20 per cent air leakage is permitted, but instruments can help reduce these losses. Reducing leakages helps in peak load management of air.
Before applying paint on the vehicle body, it must be kept in a separate chamber, where it is completely dried. This is known as the baking process. The efficiency of the heating dryer must be measured periodically.
Kalidas Bhangare, managing director, Testo India Pvt Ltd, says, “Testo 440 measures multiple parameters in the paint shop using different probe connections. Along with a hot wire probe, it measures and restricts desired air velocity. Testo 440 with IAQ probe maintains the air quality of the workspace.
“Testo dew point transmitters regulate and monitor dew content in the sprayed air in paint shop applications.
“Testo compressed air counters determine and avoid any kind of air leakages in the process.
“Testo humidity and temperature transmitters monitor critical climate during process engineering. These allow the operator or engineer to maintain the necessary conditions.
“Testo flue gas analyser, Testo 320 and Testo 330 measure the efficiency of heating dryers in the baking process.
“Thermal imagers check cold air leakage from windows and doors, and monitor the thermal profile of tyres in wear-and-tear testing, temperature of brakes, exhaust silencer and engine (with complete thermal profile of the engine).”
Software platforms for automotive testing
FlexLogger is a configuration-based, data-logging software that targets ad-hoc measurements for validation of physical systems prevalent throughout automotive sub-systems. The software is designed to configure and execute measurement and logging tasks without programming.
CompactRIO with DAQmx is a measurement and control platform that combines the powerful, reconfigurable field programmable gate array (FPGA) of CompactRIO with DAQmx driver API for host side of the application. It combines the best of CompactDAQ and CompactRIO, while upgrading the controllers with time-sensitive networking capabilities for network determination and reliability.
Jeff Phillips, head – automotive marketing, National Instruments, says, “NI’s open software-centric platform provides flexibility and customisations necessary to meet current and future automotive test needs, while maintaining the legacy of test systems and reducing development time. It can take any measurement on any network bus, and combine electrical measurements with physical ones to validate a system of systems, such as adaptive cruise control or lane-keep assist.
“The software-defined platform is a collection of highly interoperable software and hardware products that meet the spectrum of needs from custom development environments to configuration-based software, and plug-in data acquisition boards to high-performance reconfigurable FPGAs for advanced processing and control. NI serves across the entire design cycle, from design and characterisation, through software and hardware validation, to mechanical and end-of-line testing.”
Challenges in T&M for automobiles
Evolution of automotive infotainment systems requires a combination of car radio, car navigation system, digital television, Internet modem, smartphone and more. Hardware supporting completely different standards may be designed on the same chip or on multiple chips assembled side by side.
As the spectrum is limited, many of these standards operate quite close to each other. Communication standards have significant proximity and may overlap in spectrum.
Adjacent channel interference is another potential problem that needs to be considered. A wanted signal is degraded because of poor power control and/or inadequate transmitter or receiver filtering.
A new era of mobility is upon us. Critical technology trends in ADAS, electric vehicles and V2X are bringing new test challenges and pressures beyond the here and now. The quickly evolving technology landscape increases the pressure to any test schedule and requirement. There is a need to ensure that test managers are confident in their ability to overcome the pressures of rapidly changing test requirements, using an open and easily upgradable platform designed for test system openness and flexibility.