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COVER STORY   AUTOMATED DRIVING








































          FIGURE 1 Six aspects of ADAS and autonomous vehicle simulation – linking via Ansys simulation platform (© Ansys)




          ing scenarios can be evaluated rapidly to   SOFTWARE AND ALGORITHM   ware, with model-based software develop-
          check whether the vehicle sensors, con-  MODELLING AND DEVELOPMENT  ment techniques makes the software
          trol algorithms and driving systems                                 robust, less error-prone and safe. Moreo-
          behave situationally as expected.   Simulations play a key role in software   ver, the model-based development of
          Ansys’s simulation platform software   development. Developing and testing sig-  embedded software along with an ISO
          connects all tools in the control loop,   nal processing routines, object recognition   26262 qualified code generator, signifi-
            FIGURE 2, to perform high-fidelity driving   functions, control algorithms and   cantly accelerates the development pro-
          simulations of autonomous vehicles.  Human-machine Interface (HMI) soft-  cess. The Safety Critical Application
                                                                              Development Environment (Scade) soft-
                                                                              ware development package in the Ansys
                                                                              simulation platform can incorporate third-
            Drive scenario model               Sensor models                  party machine learning software and neu-
            Creates a model of the virtual world and animates  “Observe” the surroundings in the virtual world of  ral network for the AI functions of ADAS
            motions of the test car and other objects in a  the drive scenario model and output processed
            test drive                         sensor signals                 and autonomous driving, FIGURE 3.
           – 3-D road and landscape model     – Sensing simulation
           – 3-D models of stationary and moving objects  – Signal processing  PMD  Cameras
           – Object sensory attributes (e. g. radar reflectivity)              FUNCTIONAL SAFETY ANALYSIS
           – Object motion definition
           – Motion simulation in time domain    Radar    Lidar    V2X
                                                                              ADAS and autonomous driving technolo-
                                    System model   GPS   Ultrasonic sensors   gies multiply the complexity of vehicle
            Vehicle dynamics model  Physics-based, high-fidelity               systems. They not only increase the num-
            Computes position, velocity and
            orientation of test vehicle  – Offline simulation                  ber of possible causes of failure but also
                                    – Real-time simulation    Signal proc. and sensor fusion  the number of failure cascade paths.
           – Vehicle mechanical model  – Test automation
           – Sub-models for vehicle attributes     Identifies objects and driving conditions from  ADAS and autonomous driving systems
                                                   sensor data
                                                                              inherently have consequences for safety –
                                                                              any failure can be catastrophic. Perform-
            Vehicle component models                                          ing functional safety analysis of such
            Uses actuator inputs and computes   Control algorithms and HMI
            response of vehicle sub-systems such as brakes   Makes main control decisions; displays critical   complex systems is tedious and error
            and steering                       information to the driver      prone. Therefore, automated functional
           – 3-D models of vehicle components  – Software lifecycle, model-based development,  safety analysis tools are indispensable to
           – Detailed multi-physics simulation     software testing, code generation
                                              – ISO 26262, functional safety  ensure safety of ADAS and autonomous
          FIGURE 2 Simulation of the control loop for autonomous driving (© Ansys)  driving systems. The Ansys simulation
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