What is HIL Testing?

Hardware-in-the-loop testing means the tests of real ECUs (electronic control units) in a realistic simulated environment. These tests are reproducible and can be automated which leads to 24/7 comprehensive testing in the laboratory, shortens validation times, and increases the range of test scenarios. Additionally testing critical corner cases can be done without creating safety problems for the device-under-test or the environment.

Advantages of HIL Testing
  • Test systems scalable from small to large
  • Simulation of the complete vehicle or integration of real components
  • Communication testing
  • Bus and restbus simulation

Typical HIL Test System

A HIL system comprises of the simulation hardware and the accompanying software. Connected to the system is the unit under test, which usually is one or more electronic control units (ECUs) containing new functions or ECU software to be tested. Depending on the use case, further real hardware components can be added to the test system, e.g., steering or the brake system.


Schematic overview of a typical HIL system with its components.

Test Management


    Data management and collaboration software with a focus on model-based development and ECU

Platform and I/O Configuration

  • ConfigurationDesk

    Configuration and implementation software for dSPACE real-time hardware

  • Bus Manager
    Bus Manager

    Configuration tool for LIN, CAN, and CAN FD bus simulation

  • dSPACE Ethernet Configuration Package
    dSPACE Ethernet Configuration Package

    With the dSPACE Ethernet Configuration Package, you can configure a dSPACE system as a simulation node in a service-oriented Ethernet network.

  • dSPACE FlexRay Configuration Package
    dSPACE FlexRay Configuration Package

    The dSPACE FlexRay Configuration Package is used to integrate dSPACE hardware as simulation or monitoring nodes in a FlexRay network.

Experimentation and Visualization

  • ControlDesk

    Universal modular experiment and instrumentation software for electronic control unit (ECU) development

  • ModelDesk

    Graphical user interface for parameterization, management, and simulation

Test Automation

  • AutomationDesk

    Powerful test authoring and automation tool for HIL testing of ECUs

SCALEXIO Real-Time and I/O Hardware


    The SCALEXIO LabBox is a compact, modular real-time system for desktop or rack-mount use.

  • SCALEXIO Rack System
    SCALEXIO Rack System

    The SCALEXIO rack system is very flexible due to extensive I/O features. All hardware is software-configurable, making it easy to adapt the system to changing project requirements.

SCALEXIO Customized System
    SCALEXIO Customized System

    The dSPACE SCALEXIO customized system is a highly versatile hardware-in-the-loop simulator that offers a comprehensive range of adaption and configuration options to meet customer-specific requirements.

  • Power HIL Systems
    Power HIL Systems

    Testing electric motor controllers, including power electronics with emulated motors and real currents.

  • Mechatronic Test Benches
    Mechatronic Test Benches

    dSPACE provides highly dynamic turn-key test benches for mechatronic components and systems.

Simulation Model

  • Automotive Simulation Models (ASM)
    Automotive Simulation Models (ASM)

    Tool suite for simulating the engine, vehicle dynamics, electrical system, and traffic environment


    The dSPACE solution for sensor-realistic simulation offers powerful visualization and physical computation functions for generating synthetic sensor data in virtual test drives.

Deep Dive – Test Phases and Test Systems in HIL Simulations

Function Testing

Function testing focuses on testing single or a few functions, including their interaction with ECU basic software. Since this kind of testing is typically an integral part of function development rather than final release testing, its focus lies on experimental usage, without systematic test automation. Hardware-in-the-loop (HIL) test systems for function testing therefore require versatile bus and network interfaces, restbus simulation on the behavior and protocol levels, or design-for-test interfaces (e.g., XCP). These types of tests are often performed by the function developers themselves and must fit on a developer’s desk.

ECU Component Testing

Typical applications for ECU tests range from software integration testing through fail-safe and fail-operational testing, to ECU release testing. Testing is therefore highly automated and based on ECU requirements to cover the high number of variants.

Test systems for ECU testing require scalable I/O and bus/network interfaces including electrical failure simulation. Furthermore, testing of buses and networks requires restbus simulation on the behavior and protocol level as well as extensive manipulation.

Testing of real components requires comprehensive plant models and simulation performance that can be increased accordingly. Ideally, the test system functions can be adapted to changing project requirements.

ECU Domain and Network Testing

ECU domain and network testing is characterized by end-to-end testing of distributed functions. This includes sleep or wake-up tests as well as fail-safe and fail-operational tests of the vehicle’s ECU network. The need for an extensive range of I/O channels as well as bus and network interfaces is characteristic for these kinds of test systems.

A multitude of plant models must be processed time-synchronously on several clustered real-time systems. To handle complex models and scenarios, strong simulation performance and multiprocessor capabilities are required. 

ECU network testing systems often run highly automated test programs around the clock, made possible by comprehensive test management systems.

Application Areas

The dSPACE HIL systems are suitable for a wide range of application areas, from automotive topics to aerospace to railway and marine.



  • Charging Technologies

    Develop and test smart charging technologies across various development phases, from software-in-the-loop (SIL) tests to hardware-in-the-loop (HIL) tests at the signal and power levels.

  • Battery Management Systems

    Developing and testing battery management systems for electric vehicles

  • Hydrogen Fuel Cells

    Developing and testing fuel cell technologies for electric vehicles

  • Power Management

    Developing and testing DC/DC converters and other power electronics components related to electric vehicles

  • Traction Motors

    The dSPACE development environment provides very flexible support for developing and testing drives for the vehicle main traction unit from the signal level to the full power level.

Autonomous Driving

  • dSPACE HIL for Autonomous Driving

    dSPACE offers a comprehensive portfolio for closed-loop and open-loop testing of high-performance computers (HPCs) for autonomous driving.

Automotive Core

  • Powertrains

    dSPACE offers hardware and software solutions for prototyping, developing, and testing all kind of powertrains systems.

  • Vehicle Connectivity

    No matter which communication technology you prefer – dSPACE solutions help you bring connected cars to the market faster.

  • Automotive Communication Systems

    dSPACE provides a broad range of software and hardware solution to cover topics such as restbus simulation, virtual bus simulation, or bus communication testing.

  • Body & Comfort Electronics

    dSPACE offers the right tools for developing and testing Body & Comfort Electronics in vehicles.

  • Chassis

    For the development and testing of new chassis control strategies, multiple components such as steering, braking, and wheel suspension have to be considered to achieve higher driving safety, comfort, and agility.

On- & Offroad Commercial Vehicles

  • Commercial & Off-Highway Vehicles

    Highly flexible and scalable development and test solutions for commercial vehicles such as trucks, buses and off-highway vehicles


  • Electric Flight

    Enabling the future of air transportation

  • Aircraft Systems

    Aircraft systems perform a multitude of safety-critical functions in all conceivable flight situations. Hardware and software products from dSPACE play a key role in ensuring the safe operation of these systems.

  • Space

    Shaping the future of space flight according to the highest standards

Industrial Automation and Transportation

  • Energy Industry

    Developing and testing technologies for the energy infrastructure

  • Rail Industry

    Develop and test alternative drives and autonomous driving for trains

  • Marine

    Develop and test alternative propulsion systems and autonomous driving for ships

  • Machinery and Power Tools

    Comprehensive solutions for machinery and power tools to bring ideas to life, ranging from control prototyping, model-based production software development, digital twins to test benches for full-power testing.

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What our customers say

Further Information


Our videos on HIL testing cover short feature demonstrations, interviews, and detailed technical introductions.

Watch our videos on HIL Testing

Use Cases

Our use cases give an even deeper insight of what you can do with hardware-in-the-loop systems.

Discover our HIL testing use cases

Success Stories

Our customers success stories give you an overview of the wide range of application scenarios dSPACE HIL simulators are being used in.

Read more about HIL success stories

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