The NI Toolchain for Engine Testing and Control System Development Based on Single-Board RIO, LabVIEW and VeriStand

Giorgio Mancini, ALMA AUTOMOTIVE

"We used NI products to develop a fully functional toolchain for engine testing and control development in a reasonably short time."

- Giorgio Mancini, ALMA AUTOMOTIVE

The Challenge:

Developing a toolchain for engine development and testing, based on NI hardware and software solutions, that includes an engine control prototyping unit, a combustion analysis system, and a test bench control system.

The Solution:

Designing the Miracle2 rapid control prototyping platform for combustion analysis and engine control prototyping and using NI hardware and VeriStand software to design the test bench system.

Miracle2 is an extremely compact and full-featured programmable platform suitable for rapid control prototyping and smart data acquisition. Designed to fulfill the tasks usually required in automotive and motorsport applications with a form factor ideal for on-board installation, Miracle2 is our solution to real-time acquisition, processing, and control prototyping.

Among its distinctive features, Miracle2 is programmable with the typical LabVIEW toolchain (both the LabVIEW Real-Time Module and the LabVIEW FPGA Module). Miracle2 is also compatible with The MathWorks, Inc. MATLAB® software, The MathWorks, Inc. Simulink® software, and The MathWorks, Inc. Stateflow® software model execution, which allows the reuse of already available software not implemented in LabVIEW for model-based applications. Standard communication protocols are also implemented (CAN, Ethernet, RS232, XCP).

The hardware features a compact package (105 x 85 x 30 mm) and a lightweight CNC machined aluminum case (400 g), designed and tested to withstand use in environments with high vibration levels and wide temperature operation (-40 °C to 85 °C). An sbRIO-9651 System on Module (SoM), which includes Xilinx Zynq, a dual-core ARM Artix-7 FPGA on top and 512 MB RAM, powers Miracle2.


Figure 1 shows Miracle2 used as a combustion analysis system (called OBI). OBI is an extremely compact and full-featured combustion analysis system suitable for use on test benches and on board. It has been tested and validated in the demanding racing world. OBI works on up to a 12-cylinder engine (24 analog inputs overall), with direct connection to crankshaft position sensors, and without any crank angle adapter needed. It performs a real-time, cycle-by-cycle and cylinder-by-cylinder evaluation of combustion parameters, which are then published on high-speed CAN bus. 

We can easily integrate OBI with ETAS INCA, VECTOR CANape, ATI VISION, or any environment supporting CAN and XCP. OBI also features a user interface for in-cylinder pressure and combustion data monitoring.

When connected to the application engineer’s laptop, the OBI user interface allows real-time streaming of cylinder pressure signals over Ethernet and high-speed data acquisition for post-processing view and analysis. We can use OBI to develop and optimize the engine calibration both on test bench and on vehicle, thanks to the additional information regarding combustion. Furthermore, if the ECU receives the combustion analysis parameters, we can perform closed-loop combustion control. OBI is also a monitoring system, as it detects any limit value violations defined by the user and saves the raw data along with a pre-event and post-event history.

Alternatively, OBI is well suited for combustion analysis and control in vehicles or motorbikes as a stand-alone system because of its 32 GB onboard data storage, which enables complete exhaust or fuel economy driving cycles or even long-run tests to be recorded.

Figure 2 shows Miracle2 used as an engine control prototyping system. We used LabVIEW to develop the control system. Additionally, we could implement models based on Simulink using the LabVIEW Model Interface Toolkit, which means we can reuse models or control algorithms with their preferred toolchain. Thanks to XCP slave drivers implemented on Miracle2, we can use any tool compliant with XCP as a measurement and calibration interface.

We used VeriStand, running on a real-time desktop PC connected to a PXI and MXI-Express RIO chassis, to implement test bench control. We can use the test bench control system to monitor tests while controlling several actuators (linear motors for clutch and accelerator, water and oil temperature valves, and more) and logging data in Technical Data Management Streaming (TDMS) format using several channel groups. Figure 3 shows the test bench control system can log data directly from the transducers connected to the input boards and exchange data with other modules such as the ECU, OBI, linear air-fuel sensor, or NOx sensor controllers. I/O types include CAN/CANOPEN, RS232, current input, voltage input, thermistors, thermocouples, voltage output, timer/counters, digital I/O, and output switches. VeriStand native functions, such as alarm management and real-time procedures, boost system development, while we can easily develop custom devices with LabVIEW for more specific function management.



We used NI products to develop a fully functional toolchain for engine testing and control development in a reasonably short time. The biggest advantages are flexibility and time saved in the development of new algorithms and tools for engine development and testing.


Author Information:

Giorgio Mancini

Figure 1. Combustion Analysis System Layout: OBI runs on Miracle2, which publishes combustion parameters through CAN and XCP on Ethernet.
Figure 2. Engine Control Prototyping System Layout: Miracle2 is used as a full bypass ECU, with external power drivers for injection and ignition.
Figure 3. Test Bench Control System Layout: Developed using VeriStand, which runs on a real-time PC connected to a PXI and an MXI-Express RIO chassis