As demand grows for new in-vehicle features, a large number of
electronic control modules are being introduced in the automobile
to increase passenger's comfort, safety, entertainment and
overall performance. The performance parameters of features such as
electronic power steering, engine management systems, anti-lock
braking systems, airbag systems, transmission systems, navigation
and entertainment systems are monitored and controlled by
electronic control units (ECUs). Vehicle-level ECU testing for
small hardware or software changes is not practical and it is
expensive. Therefore, bench-level testing is an effective way to
ensure ECU functionality, as long as the tester is able to
effectively simulate vehicle conditions during the bench test.
Bench-level testing involves use of either static or
programmable simulators to simulate the required functionalities.
The programmable simulator is generally a better tool than the
static simulator because it is configurable. This paper gives an
overview of how MATLAB "Simulink® model can be used to
configure a programmable vehicle simulator. Simulink® is a powerful
modeling tool that provides an efficient way of simulating the
system under design. The modeled system can be converted into an
executable which can be deployed on to the target hardware
(simulator) and can be run in real time.
This paper explains about how to configure the vehicle simulator
for various functionalities using MATLAB -Simulink® model. This
paper focuses on the following functionalities: vehicle interface,
instrumentation support, supporting of periodic data acquisition
(DAQ) using CCP (CAN calibration protocol) and XCP (universal
calibration protocol), periodic data stimulation (STIM) using XCP,
simulation of fault conditions to test the ECU, simulation of
diagnostic test tool to read diagnostic trouble codes (DTC),
simulation of power waveform test tool, replay vehicle logs on the
hardware.
The simulator is used to test the ECU in a laboratory,
simulating the conditions that would occur if the ECU was in the
vehicle and exposed to real driving scenarios. Real-time Vehicle
logs can be replayed back on the ECU. When performing in-vehicle
testing, testers must provide diagnostic services to read the fault
and instrumentation tools to re-flash the software. In-vehicle
tests also must account for battery supply variations, necessary
diagnostics and have comprehensive vehicle logs to ensure test
repeatability. MATLAB -Simulin® modeling can be used to simulate
all such scenarios. This article explains simulation of
functionalities mentioned above, using MATLAB -Simulink\R
model.