Data Acquisition for Vehicle Testing

The SmartSolo Scientific Data-Acquisition System was designed with vehicle testing in mind. As SmartSolo's most computationally powerful data-acquisition system, the M1000 is the core of the vehicle testing data-acquisition network. Providing four general-purpose CAN channels, the M1000 is CAN bus and CAN FD compatible. When integrated with the M1000 measurement modules, a complete system is capable of measuring temperature, strain, pressure, load, and many other parameters. The M1000 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 M1000 CAN bus allows time-synchronized storage of vehicle computer data with independently measured data from the M1000 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 M1000 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 M1000 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 SmartSolo Scientific measurement modules can be distributed throughout the vehicle. Each module is connected to a central SmartSolo DAQ. This networking capability decreases the quantity and lengths of the sensor cables between the sensors and the SmartSolo. Fewer sensor cables reduce cost, improve system simplification, and lessen the risk of signal corruption from noise.

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

1. The SmartSolo Scientific has a built-in GPS and precision master clock.

a. The pulse-per-second signal from the GPS is accurate to 1 µs. If enabled, the SmartSolo Scientific 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.

b. 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 M1000 and measurement modules, the measurements are all synchronized to the master clock of the M1000 (sourced by either the GPS or precision on-board clock) via the CAN Peripheral Interface (CPI) or Ethernet Peripheral Interface (EPI) measurement buses.

a. 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.

b. 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 M1000 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 M1000 DAQs is compatible with almost every commercially available sensor, our systems give you the freedom to use the sensors that best meet your application. M1000 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, 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 M1000 measurement modules directly to a PC or scheduling remote, automated data collection from the M1000. 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