Terms and definitions

Co-simulation

Type of Functional Mockup Unit (FMU).
Co-simulation FMUs contain their own numerical solver. This importing tool sets the FMU inputs, asks the FMU to step forward a given time, and reads the FMU output after the step is completed. With OSMP, models are packaged as valid FMI-2.0 FMU for co-simulation.

Ego vehicle

Externally controlled vehicle used for scenario descriptions.
For evaluation of automated driving systems, the ego vehicle is the vehicle that is controlled by the system-under-test. For human-driver experiments, the ego vehicle is the vehicle that is driven by the human driver.

Environmental effect model

Information set that deals with effects and phenomena caused by, for example, shadows and occlusions, weather effects, the physics of a sensor, or the pre-processing of raw sensor data. An environmental effect model has a SensorView message as input, which comes from the environment simulation, and a SensorView message as output. The output is sent to the sensor model.

FMI (Functional Mockup Interface)

Free standard that defines a container and an interface to exchange dynamic models using a combination of XML files, binaries, and C code zipped into a single file.

FMU (Functional Mockup Unit)

Simulation model that adheres to the FMI standard.

GroundTruth

Information set that describes the whole simulated environment around any simulated vehicle. It is based on data available to the simulation environment.

Logical model

Logical models consume SensorData messages and produce SensorData messages.

Examples: - Sensor-fusion model: Combines the output of multiple sensor models to produce data with less uncertainty - Fault-injection model which, contrary to a sensor-fusion model, may be used to increase uncertainties

Object coordinate system

Local coordinate system whose origin may be identical to the center of the object’s bounding box. If the origin is not identical to the center of the object’s bounding box, the object documentation provides the actual definition.

OSI (Open Simulation Interface)

Specification for interfaces between models and components of a distributed simulation. OSI has a strong focus on environmental perception of automated driving functions. It also specifies interfaces for modeling traffic participants.

OSMP (OSI Sensor Model Packaging)

Specifies how models that use Open Simulation Interface (OSI) in simulation environments are packaged in accordance with the Functional Mock-up Interface 2.0 (FMI 2.0).

Sensor coordinate system

Coordinate system for all entities that are part of SensorData. The origin is the mounting position of the physical sensor or a virtual mounting position, depending on the OSI message.

Sensor model

From OSI’s perspective, a sensor model refers to the part of a sensor system model that includes processing algorithms at an object detection level. Sensor models consume SensorView messages and produce SensorData messages. Sensor model output does not represent raw data but detected features or classified objects.

SensorView

Information set that is derived from ground truth and used as input to sensor models, environmental effect models, or traffic participant models.

Traffic participant model

Information set that models the dynamic behavior of moving objects by deciding how to change position, orientation, and other states of the dedicated moving object. To do this, it reacts on input given by SensorView and TrafficCommand resulting in TrafficUpdate as output.

Global coordinate system

Coordinate system for all entities that are part of ground truth. The global coordinate system is an inertial x/y/z-coordinate system. The origin is the global reference point that is determined by the environment simulation. This reference point may be derived from map data or other considerations.