Tuesday, January 26, 2016

Software testing: What to do with a Virtual Object-under-test?

Since its first version, ISOLAR-EVE allows for the configuration and generation of a Virtual ECU directly out of an AUTOSAR configuration. And from this very first version, we at ETAS understood that a Virtual ECU is just an object-under-test, and the key aspect in the virtualization of the testing activities is to be able to integrate it into a testing environment in order to perform the necessary tasks.

That’s why ISOLAR-EVE development is consistently going into the direction of more openness and integration possibilities. For this we’re using a unique technology, which can be seen as the wiring harness of the Virtual ECU: the Virtual Devices. I wrote more about this in a previous blogpost. Thanks to this technology, an ETAS Virtual ECU generated by ISOLAR-EVE can be integrated in potentially all testing environments.

With the development of ISOLAR-EVE V3, released in December 2015, we improved further the “cabling” possibilities of the Virtual Object-under-test. Many options were available already with the V2.2, like the connection to Simulink, the FMU V1 generation, or the coupling to CANoe.

Following consistently the same development plan, we now provide:
  • An integrated interface to the model-based testing tool RT2. Test scenarios developed with ETAS-RT2 can then directly be applied to the ETAS Virtual ECU, without further manual configuration
  • The possibility to use the CANoe connection between 2 different PCs. Thanks to this, it is no longer required to have EVE and CANoe licenses available on the same PC to connect the Virtual ECU to a Virtual ECU network
  • The support of FMI V2.

Furthermore, testing activities are part of the development process and should be possible in an integrated environment whenever the user needs. For instance, it shall be possible to test a software architecture easily as soon as possible. For this, we are now integrating ISOLAR-EVE with the ETAS Authoring Tool ISOLAR-A.It is therefore now possible to generate a Virtual ECU and test it at any time during the software design phase, assuming the internal behavior of the Software Components is available, e.g. ETAS ASCET or Simulink models, or directly as C-Code.

Tuesday, January 5, 2016

Test your battery management controllers without batteries!

Are you a developer sitting next to batteries all day long as your work on your test code? Did you have to age your batteries to test your controls? How often do you have to change the batteries in your pack? Save yourself the hassle and the risk of working with batteries with the help of the ETAS Battery Cell Simulator.

The ETAS Battery Cell Simulator [BCS] is fully compatible with ETAS’ LABCAR Hardware-in-the-Loop [HiL] system to simulate every input/output on your controller. Battery Packs up to 200 series cells can be replaced by hardware and a model simulating your individual battery cells. Each cell parameter is controlled independently with ranges of 0 V and 0.85 – 8 V with an accuracy of 500 uV in less than 4 ms with a maximum source current of 3 A. Each cell simulator is built with a load feature allowing use in active and passive balancing topologies with a maximum sink current of 2.5 A with an accuracy of 2 mA. These currents can be combined with use of a dual or quad mode putting 2 cells or 4 cells in parallel, respectively. Dual mode provides a source current of up to 6 A and a sink current of up to 5 A, whereas quad mode provides a maximum source current of 12 A and a maximum sink current of up to 10 A.

The high-precision current measurement system built into an individual cell can reach an accuracy of 10 uA with a resolution of 305 nA providing you a very accurate balancing and leakage current measurement. The BCS also comes with an integrated Coulomb measurement per cell to compare with your device under test algorithm at an accuracy of 2 x 10-7 As.

Each cell contains a built in feature of voltage sensing to compensate for the resistance losses between the HiL and the device under test. The BCS is also capable of injecting faults through integrated fault simulation units providing you open circuit, short circuit, polarity reversal, and external voltage injection to two external voltages reducing your need to spend hours manually creating these scenarios on your test bench.

As your cells charge and discharge the temperature of your battery pack fluctuates. ETAS has your back here. Modular thermistor simulators can easily be built into your system to replicate the 0 Ω – 8 Ω characterized reactions of your NTC or PTC resistors in your pack with an accuracy of 1 Ω.

Here’s something else to think about. With the seamless integration of the BCS into the LABCAR system, you can now create models to simulate your device with a user-friendly graphical interface. These models can be imported from MATLAB, ASCET, and C-code allowing you the flexibility to use any tool that compiles to C-code with minimal modification, and then you can link your inports and outports from each module to one another or to the HiL hardware devices. Once built, this allows your host computer to communicate to a simulation target in the LABCAR called the real-time PC [RTPC] which controls all of the HiL hardware with a cycle time down to 10 us. If required, FPGA models can be integrated to reduce the time below 1 us. The LABCAR architecture is built on a standard PCIe interface allowing the connectivity of 3rd party devices which may be required for your controller.

This sounds too good, doesn’t it? Try this. ETAS LABCAR HiL systems are capable of running LABCAR-AUTOMATION, a graphical software package that allows you to develop test cases, manage them, and execute them to ensure high software quality on your devices without the need of manual testing providing more economic and reproducible results. AUTOMATION is fully integrated with LABCAR, data logging, fault insertion modules, evaluation of the J1699 OBD protocol, fault memory access, and can be used with many 3rd party devices. Also, all .Net compatible languages for test case programming, such as C# and Python, are supported.

Additional equipment from ETAS allows you to integrate your system more seamlessly, have access to the signals, and create additional fault simulations to your cell or temperature wires. Simple harness sets are available to connect between your HiL and your controller by connecting the open ended wire cell wire and voltage sensing wire to your BMS controller. A break-out box is available to prove you with access to signals in between the HiL and your controller. This grants you the ability to insert manual faulting and easier access to troubleshoot your controller. In hand with the break-out box, a cell simulation isolation node cable is available for single cell measurement and cell cascading.

For additional information or to schedule a demonstration, please contact us at 1-888-ETAS-INC or sales.us@etas.com or just comment below.