Simulation method of the ATP driver-machine interface based on MDA

MDA is the collection of a series of Standards (MOF, UML, CWM and XMI)
and Technology (CORBA, Java, C++, etc.), which are the basis for supporting
MDA [2]. The core idea of MDA is to form a CIM (Computation Independent
Model) based on users’ needs, including the development purposes, performance
and requirements of the software to be developed in the system development
process [3]. According to the CIM model, using the above standards and
technology, the platform-independent, highly summarized models are abstracted
and concrete, which are called PIMs (Platform Independent Models). Then, the

transform rules are defined based on the specific implementing technology
platform. The PIM is transformed to the PSM through the defined transformation
rules and tools, and the PSM will be converted into executable code
automatically.
The development process of the MDA-based system is shown in Fig. 1.
Using MDA, the system development process is detached from the building
process of two models: one is the establishment of the PIM; the other is the
establishment of the PSM, and the key technology is the conversion between
the PIM and the PSM. In the beginning of the system development, the PIM
should be established, which is independent of the specific implementation
technology and platform and is the high-level abstraction of the system. Then,
according to the transformation definition, the PIM is converted into the PSM,
which is closely related with the specific implementation technology and
platform. The framework of the MDA includes the PIM, PIM description
language, transformation rules, PSM, PSM description language and several
other elements . In traditional software development processes, the model
represents not only the demand, but also the realization of specific
technologies. Using MDA, models are classified into PIM, representing
demand, and PSM, representing the realization of specific technologies, and

therefore, the demand and technologies are related.
To develop an ATP driver-machine interface simulation system, the
requirement must be analyzed above all, and the function of the ATP drivermachine
interface could be described using UML. On top of this, the PIM was
established, which did not contain any platform-related details. In the description
of the PIM, the demand should be summarized and summed up; restraint
describing language should be used to achieve the transformation. After the
completion of the PIM description, the PIM was mapped to a particular
simulation development platform, and then the PSM was obtained. The PIM-to-
PSM transformation rules were divided into two parts. One part is to carry out
the communication function, since the core function of the ATP driver-machine
interface is to accomplish communication with the Vehicle Computer . In
order to ensure the accuracy of communication, the automatic conversion mode
was used in this part . The other part is to complete the construction of the
modules and interaction among the modules according to the definition of the
ICV model. The manual mode was used in this part. The PSM was generated by
a combination of these two conversion methods and then the ultimate simulation
system was completed.
The comparison between the MMI development framework and the MDA
development framework is shown below.

Simulation systems of rail line

Safety assessment of rail systems

Re-design of application of the core system for the specified rail lines

Design and development of the core systems

railway control systems and their core systems

JavaScript objects

animation loop using requestAnimationFrame