Automotive Industry Insights

ASAM XIL

Description
The ASAM XIL standard (see https://www.asam.net/standards/detail/xil/ for details) defines interfaces that test automation tools can use to connect to and communicate with test benches. Since the ASAM XIL standard supports not only HIL but also MIL and SIL systems, it can be used in all phases of the development and test cycles. Test automation tools that are ASAM XIL compliant enable interoperability between different test tool and test bench vendors.

The standard provides two levels of abstraction that are built on top of each other: the test bench layer and the framework layer.

The test bench layer defines interfaces for access to different technical areas of a test bench, the so-called test bench ports.

Currently available ports are:
The model access port (MAPort) for access to the simulation model. It is possible to read and write parameters, to capture/record signals, and to generate signals.

The ECU measurement port (ECUMPort) and ECU calibration port (ECUCPort) provide access to measurement and calibration tools. They allow the reading and capturing/recording of measurement variables of an ECU as well as the reading and writing of internal calibration values of the ECU.

The network access port (NetworkPort) provides access to network communication, such as frames, PDUs, and signals on CAN or Flexray.

The diagnostic port (DiagPort) communicates with a diagnostic system to read data via diagnostic services from an ECU or functional group.

The electrical error simulation port (EESPort) controls electrical error simulation hardware. It allows different types of electrical errors to be set.

The framework layer is built on top of the test bench ports and provides access to the test bench at a higher level while abstracting more vendor-specific details and configuration options. The purpose of the XIL framework is to achieve effective decoupling between test cases and test benches to improve test reuse.

The XIL framework provides port-independent reading, writing, and capturing of variables, conversion of units and data types, mapping of variable identifiers, and configuration and life cycle management of the test bench ports. Therefore, the XIL framework uses functionality of the XIL test bench ports. The XIL framework also allows the configuration of data acquisition from different data sources, that is, from different XIL test bench ports. The time traces of variables from these different data sources are assembled on a common time basis.

With both XIL test bench and XIL framework, data capturing/recording can be performed based on memory for online processing or based on files into standardized measurement formats (ASAM MDF 4.0 or higher) for data reuse in a later process stage.

References
https://www.asam.net/standards/detail/xil/
https://www.asam.net/standards/detail/xil/wiki/

Status
The standard is well established. The current version is XIL 2.2. Version XIL 3.0 is under development (see https://www.asam.net/project-detail/asam-xil-v300/).
According to ASAM XIL 3.0.0 project page (https://www.asam.net/project-detail/asam-xil-v300/), these are the new features for XIL 3.0 to be developed:

• Introduction of a new value container with generic complex data types
• Introduction of a new test bench port for access to service-oriented communication (SOC): this covers tests of service provider or service consumer as well as integration tests in the network and storage of SOC data in ASAM MDF
• Traceability of test case execution, including logging of events
• Usage of complex setup routines to react to status events of the test system
• Monitoring of variables and states by streaming instead of polling
• Error injection modification to stimulate function signals
• Access to system description via an API
• Rework of the existing ECUM and ECUC test bench ports to one common ECU port
• Usage of the standard in Linux environments

All in all, these are many general improvements, but some have a strong relation to other standards and ADAS/AS development needs.

Current role and relevance with regard to ADAS/AD
Current relations to other standards:

ASAM MDF (Measurement Data Format)
Currently, the XIL standard requires that measurement results be stored in ASAM-MDF-compliant files of version 4.0 or higher.
XIL 3.0 is targeting a solution for the storage of complex data from service-oriented communication in MDF. This may overlap with current MDF activities on the support of image, radar, lidar, and sensor logging (see https://www.asam.net/project-detail/asam-mdf-image-radar-lidar-sensor-logging).

FMI (Functional Mock-up Interface)
XIL relates to the FMI standard in terms of variability of simulation variables.
Furthermore, the growing relevance of (distributed) cosimulation-based test systems raises challenges that are relevant to both standards and may require alignment (esp. regarding system configuration and simulation control).
The relation of FMI to the ASAM XIL standard needs to be evaluated.

Future relations to other standards:
AUTOSAR Adaptive Platform and SOME/IP
The future introduction of an XIL SOC (service-oriented communication) port will eventually have a strong relation to the standards AUTOSAR Adaptive Platform and SOME/IP (Scalable Service-Oriented Middleware over IP). However, it is expected that the new SOC port interfaces will encapsulate and abstract the technical details of these standards, similar to what is already being done today with the existing XIL test bench ports.

ASAM OSI
The increasing usage of ASAM OSI for environment models (coupling of sensors, agents, etc.) may raise the need for the XIL standard to extend its functionality accordingly to support MIL, SIL, and HIL testing for future AD applications. Especially the new data types and the binary data type used by OSI may need some adaptions allowing OSI data to be captured, recorded, or stimulated.
In addition, the specifics of configuring and controlling scenario-based environment simulations may raise further requirements of the XIL standard. The relation of ASAM OSI to the ASAM XIL standard needs to be evaluated.

Additional study group findings on ASAM XIL
The study group has identified interrelations between the standards FMI, ASAM MDF, ASAM OSI, and ASAM XIL as described in this section. The recommendation is to check on the coordination activities between the different standardization projects.