Vehicle Testing

Campbell Scientific's vehicle data acquisition systems (VDAS) are used by vehicle manufacturers worldwide. Our systems feature versatility, portability, and reliability. These three qualities allow you to configure systems that meets your exact needs, take them anywhere you need measurements, and get accurate, consistent data, even in extreme environments. From scorching summers to frigid winters, wind tunnels to abusive test tracks, our data acquisition systems provide accurate, timely, and reliable data.

Vehicle Test System Benefits

1. Rugged design allows vehicle test systems to withstand vibration, shock, and temperature extremes.
2. Nearly every commercially available sensor can be used in our systems.
3. Systems are calibrated against NIST standards.
4. Communication options include direct wire to PC or laptop and many wireless possibilities.
5. On-board statistical and mathematical capabilities provide data reduction on-site.
6. Internal preset gain ranges eliminate the need for costly external signal conditioning while allowing excellent measurement resolution.
7. Multiple systems are available with varying channel counts, sampling rates, and physical sizes.
8. Multiplexers and other peripherals are available for expanding systems.
9. Systems are durable—many are still in use after 15 years.

Data Acquisition for Vehicle Testing

We offer a full line of data acquisition systems. Scan rates can be programmed from every few hours to 100,000 times per second, depending on the system model. Measurement types, processing algorithms, and recording intervals are also programmable. Our systems can also store data transmitted from the vehicle's on-board computer via CANbus, allowing time-synchronized storage of vehicle computer data with the data acquisition system's independently measured data.

On-board instruction sets contain programmed algorithms that process measurements and output results in the desired units of measure. For example, data can be displayed as rainflow or level crossing histograms. These rainflow and level crossing algorithms allow processing for extended periods of time, not just a limited number of cycles. Our instruction sets also allow unattended measurement and control decisions based on time or conditional events.

Sensors for Vehicle Testing

Because our VDAS are compatible with almost every commercially available sensor, our systems give you the freedom to use the sensors that best meet your application. Most sensors connect directly to our dataloggers, eliminating costly external signal conditioning. Channel types include analog (single-ended and differential), pulse count, switched excitation, continuous analog output, anti-aliasing filter, and digital I/O.

Typical sensors used with our systems include: thermocouples, pressure transducers, pulse pickups, flow transducers, potentiometers, strain gages, load cells, digital switches, accelerometers, LVDTs, and tilt sensors. Our configurable dataloggers, the CR9000X-series and CR9000-series, allow you to choose modules with the channel types that best fit your application. The number and type of channels on most of our VDAS are expandable using multiplexers and other measurement peripherals.

Data Retrieval

On-site communications interfaces for retrieving, storing, and displaying data include direct connection to a PC or laptop, PC cards, storage modules, and a datalogger keyboard/display. A heads-up-display is also available for data display when driving a vehicle. Telecommunication options include short-haul, telephone (landline, cellular, and voice-synthesized), radio frequency, multidrop, and satellite.

Software

Our PC-based support software simplifies the entire data acquisition process, from programming to data retrieval to data display and analysis. Robust error-checking ensures data integrity. We can even help you post your data to the Internet. PC9000 is a full-featured package that is included with the CR9000X systems. PC9000 is also compatible with our CR9000 and CR5000 dataloggers, although the software is purchased separately.

PC9000 features include:

1. Easy-to-use Program Generator with step-by-step programming assistance.
2. Real-time data display tools, such as histograms (rainflow & level crossing), virtual meters, virtual oscilloscopes, X-Y plotters, FFTs, and alarm listings.
3. Historical display of data in time series, rainflow, level crossing, and FFT formats.
4. Manual and scheduled data collection in multiple data formats.

Testing Possibilities

Our data acquisition systems have been instrumental in testing the following:

General Testing

• Chassis monitoring
• Road noise
• Vehicle speed
• Steering
• Air bag
• Distance traveled
• Humidity
• Hot and cold soaks
• Wind tunnel
• Altitude
• Geographic location

Fuel System Testing

• Line pressure
• Tank pressure
• Temperature
• Flow

Climate Control Testing

• Ambient air temperature
• Supply air temperature
• Solar radiation
• Fan speed
• Interior temperature
• Time to comfort
• A/C on and off
• Refrigerant pressures

Suspension Testing

• Strut pressure
• Spring force
• Travel
• Mounting point stress
• Deflection

Brake Testing

• Line pressure
• Pedal pressure/travel
• Line/pad temperature
• ABS

Engine Monitoring

• Oil pressure
• Oil temperature
• Water pressure
• Water temperature
• Fuel injector timing
• Crank position
• RPM
• Noise level
• Heat detection
• Catalytic converter
• Cooling fan speed
• Manifold pressure
• Manifold temperature
• Exhaust gas temperature

Data Acquisition for Vehicle Testing

The GRANITE™10 Data-Acquisition System was designed with vehicle testing in mind. As Campbell Scientific’s most computationally powerful data-acquisition system, the GRANITE™10 is the core of the vehicle testing data-acquisition network. Providing four general-purpose CAN channels, the GRANITE™10 is CAN bus and CAN FD compatible. When integrated with the GRANITE™ measurement modules, a complete system is capable of measuring temperature, strain, pressure, load, and many other parameters. The GRANITE ™10 DAQ can support multiple measurement rates simultaneously, ranging from every few hours to more than 10,000 measurements per second. Measurement types, processing algorithms, and recording intervals are also programmable. The GRANITE™10 CAN bus allows time-synchronized storage of vehicle computer data with independently measured data from the GRANITE™ DAQ.

On-board instruction sets contain programmed algorithms that process measurements and output results in the desired engineering units. For example, data can be displayed as rainflow or level-crossing histograms. These rainflow and level-crossing algorithms allow processing for extended periods, not just a limited number of cycles. Our instruction sets also allow unattended measurement and control decisions based on time or conditional events.

Modular Design

The modular architecture of our GRANITE™ system allows each measurement module to independently connect directly to a PC or DAQ. As an independent module, the real-time measurements can be displayed directly on the PC. One or more measurement modules can be connected to the GRANITE™10 DAQ to create the perfect networked configuration for each application. When connected, they form a time-synchronized, distributed data-acquisition system.

Distributed Networks and Synchronization

Multiple GRANITE™ measurement modules can be distributed throughout the vehicle. Each module is connected to a central GRANITE™10 DAQ. This networking capability decreases the quantity and lengths of the sensor cables between the sensors and the GRANITE™10. Fewer sensor cables reduces cost, improves system simplification, and lessens the risk of signal corruption from noise.

Synchronization is key to the success of a distributed network. There are three significant levels to the GRANITE™DAQ synchronization:

1. The GRANITE™10 has a built-in GPS and precision master clock.
   1. The pulse-per-second signal from the GPS is accurate to 1 µs. If enabled, the GRANITE™10 will phase lock its operating clock to within 200 ns of the GPS clock. So, multiple independent DAQ systems spread over potentially vast geo-spatial regions can be synchronized with a maximum timing error between DAQ systems of 1.2 µs.
   2. Independent of the GPS, a temperature-compensated, high-precision, on-board, real-time clock will keep its own time with an accuracy of ±3 min/year.
2. Within a single DAQ system, comprised of a GRANITE™10 and GRANITE™ measurement modules, the measurements are all synchronized to the master clock of the GRANITE™10 (sourced by either the GPS or precision on-board clock) via the CAN Peripheral Interface (CPI) or Ethernet Peripheral Interface (EPI) measurement buses.
1. CPI synchronization between measurement modules in the same DAQ is ±5 µs. The overall physical range of the bus varies up to 2,000 ft depending on the data rate.
2. EPI synchronization between measurement modules in the same DAQ is ±50 ns. The physical range of the bus is 300 ft per network connection. Daisy-chained connections can span thousands of feet.
3. For extremely time-based-sensitive applications, the GRANITE™ SPECTRUM measurement modules are used with EPI synchronization. Within each module, the analog electrical signal delay is calibrated and compensated to reduce the timing delay mismatch to ±10 ns channel-to-channel.

Sensors for Vehicle Testing

Because each of the GRANITE™10 DAQs are compatible with almost every commercially available sensor, our systems give you the freedom to use the sensors that best meet your application. GRANITE™ measurement module channel types include analog (single-ended and differential), temperature (thermocouple and thermistor), bridge, switched excitation, continuous analog output, anti-aliasing filter, and digital input/output (I/O).

Typical sensors used with our systems include thermocouples, pressure transducers, pulse pickups, flow transducers, potentiometers, strain gauges, load cells, digital switches, accelerometers, Linear Variable Differential Transformers (LVDT), and tilt sensors.

Data Retrieval

Communication interfaces for retrieving, storing, and displaying data include direct connection to a PC or laptop, microSD cards, Ethernet, and several options for wireless communication (including built-in Wi-Fi).

Software

Our PC-based software options support connecting the GRANITE™ measurement modules directly to a PC or scheduling remote, automated data collection from the GRANITE™10. Real-time monitoring and control simplify the entire data-acquisition process, while robust error-checking ensures data integrity. We can even help you post your data to the Internet.

Testing Possibilities

Our data-acquisition systems have been instrumental in testing the following:

Field Testing

• Chassis monitoring
• Road noise
• Vehicle speed
• CAN bus data acquisition
• Environmental conditions
• Performance
• Temperature monitoring

Laboratory Testing

• Extreme temperature environments
• Large channel counts
• Chamber parameters
• Component longevity/durability
• Chassis monitoring