An Embedded Real-Time Traffic Simulation Environment on Vehicle-In-Loop Framework for Autonomous Driving
Typ
Examensarbete för masterexamen
Program
Embedded electronic system design (MPEES), MSc
Publicerad
2021
Författare
CHANDRASHEKAR, VARSHA
WANG, XINYUAN
Modellbyggare
Tidskriftstitel
ISSN
Volymtitel
Utgivare
Sammanfattning
Autonomous driving(AD) and Advanced Driver Assistance (ADAS) functions are
rapidly evolving. Extensive testing of these systems is necessary at every stage of
development. To ensure high performance and safety of ADAS and AD, the development
of test technology has to happen at least at the same pace to support
development. In order to cater to a more realistic testing, Vehicle-in-loop (VIL)
methodology integrates a real vehicle into a virtual traffic environment to validate
the vehicle’s behaviour. This is both safe and resource efficient. Since it involves
both physical/real actors and virtual actors from the simulator, for a timely execution
of a test scenario we need a closed loop simulation, with each actor on the test
track and simulator being aware of one-another. Closed loop simulation requires
updating of trajectories dynamically to each actor based on their dynamic positions
to be able to execute a defined traffic scenario. There needs to be synchronized flow
of information to and from the actors in real time. In this thesis, we worked on the
development of a server on an embedded real time hardware platform. The server is
a centralized controller steering test targets along given real time updated trajectories.
This server is capable of controlling all the test targets by communicating with
them via User Datagram Protocol (UDP) over Wi-fi, in a synchronized manner to
provide for a closed loop simulation in real time as a part of VIL. We also studied an
existing traffic simulator developed in Simulink and analyzed the different sources
of latencies in the system. These latencies lead to scenarios failing to execute in
real time due to synchronization errors. As an approach to solving these timing
issues, we deployed this simulator onto the same real time platform as the server.
The test results showed that the server could steer a Radio Controlled (RC) car in
synchronization with the virtual actor generated by the simulator both in open loop
and closed loop. Synchronization was achieved by making all the actors refer to a
global time stamp and by reducing latencies in the simulator to meet all real time
execution constraints.
Beskrivning
Ämne/nyckelord
VIL , Closed-loop , Server , Simulator , Real-Time systems , Hardware Platform , UDP