Балашов eucass 2013 (Лекции 2014-2015), страница 4

Real-time test execution environment which provides: Distributed execution of TCs on several instrumental computers; Data exchange and time synchronization between the instrumental computers; Remote access for the TCs to the onboard interface adapters on different instrumental computers throughthe testbench Ethernet network; Data exchange between tests and SSH systems; Data exchange between tests and the tested RTA devices; Access of tests to the channel monitoring results; Interaction with the experiment control subsystem; Recording of the testing results in the form of testing logs and testing events traces.4. Experiment control subsystem which supports user’s interaction with tests, in particular for interactive testing.5.

Subsystem for online visualization of the testing process and results, which is closely integrated with theexperiment control subsystem.6. Experiment results processing subsystem which supports: Display of the testing results in the form of testing logs, time diagrams, parameter value graphs, channelmonitoring logs; Generation of reports on the testing results.8A FAMILY OF TESTBENCHES TO SUPPORT TESTING OF REAL-TIME AVIONICS SYSTEMS7.Server subsystem which supports: Version control for the testing scripts’ source code, testbench configurations, testing logs; Interaction with the onboard interfaces database; Remote access to the testbench repository from all testbench computers.Access to all the listed subsystems is provided to the user through the Integrated development environment.6. Architecture of testbenches based on the FT toolsetThe FT toolset described in Section 5 is used in Sukhoi design bureau for over seven years as the main software toolfor testing of RTA systems.

Architecture of FT toolset-based testbenches, including typical components and schemeof their composition, evolved through years of toolset industrial application. The present section describes thisarchitecture.An FT toolset-based testbench typically includes the following components: Instrumental computers intended for running tests and performing data exchange with the RTA systemthrough onboard interface channels (presently, MIL STD-1553B, ARINC 429 and Fibre Channel); Specialized signal simulation hardware (SSH) systems operating under control of instrumental computers; Workstations for test engineers and RTA software developers; Server responsible for centralized functions such as testbench repository keeping and sharing, userauthentication, etc; Network of onboard interface channels connecting RTA devices to instrumental machines and SSHsystems, and RTA devices with each other; Auxiliary equipment, including systems for power supply and cooling, technological networks, racks, etc.Structural scheme of a typical FT toolset-based testbench is shown in Figure1.InstrumentalcomputersAvionicsdevicesWorkstationsOnboardchannelsnetworkSSH systemServerEthernetnetworkFigure 1: Structural scheme of an FT toolset-based testbenchThe number of instrumental computers, workstations, number and types of the onboard interface channels aredefined by the specifics of the RTA system under test, as well as by the tasks of the particular testbench.All computers of the testbench (workstations, server, instrumental computers, SSH systems) run the Linux operatingsystem.

In particular, instrumental computers and SSH systems run Linux with real-time extensions.In addition to the Ethernet network, the instrumental computers are connected by the time synchronization network.It connects LPT ports of the computers and transfers precise time signals from the “master” computer to the othercomputers. Time synchronization protocol guarantees deviation between computers’ clocks of no greater than 10 us.An example of SSH system is the television signal simulation hardware (SSH TV).

It is a multiple-computer systemintended for generating, sending, receiving and recording high-speed video streams simultaneously through severaloptical channels. SSH TV operates as a source of test video data for the RTA system video processing devices, aswell as a recorder for output of these devices.

SSH TV is also utilized for testing the onboard display devices.9V.V. Balashov, M.V. Chistolinov, R.L. SmelianskyStatic (individual frames) and dynamic (video sequences) test streams are prepared in advance, prior to the start oftesting. Selection of the video stream to be sent to a particular channel at the given time is performed by the testingscript running on an instrumental computer, or by the user through the online experiment control tool.7. The family of testbenches for RTA systems testingThis section describes the industrial application of the FT toolset presented above. A family of FT toolset-basedtestbenches was developed for Sukhoi, each of the testbenches aimed at a particular activity (or a group of activities)of the RTA system lifecycle.

Complexity of a testbench corresponds to the complexity of the RTA subsystem to betested on the testbench.Testbenches used in Sukhoi are integral parts of the technology for data control system (DCS) development. DCSincludes the central computer, a set of display devices, and some auxiliary devices. DCS onboard channel networkincludes: Several MIL STD-1553B channels connecting the DCS to other RTA devices; Dozens of ARINC 429 channels for data exchange with legacy devices; A Fibre channel network for high speed data exchange, including transfer of video data.Main representatives of the testbench family, as well as their tasks, are described below.

All the testbenches share thecommon architecture described in Section 6. As a total, the family of testbenches covers all the testing activitiesmentioned in Section 2.1. Testbench for testing and debugging of an individual RTA device’s software. This testbench is intended forworking with a single RTA device, for instance with the most complex one – the central computer. The main purposeof the testbench is debugging the RTA device’s software on the target hardware, as well as preparation of the deviceto integration with other RTA devices.

For final checks of the device’s readiness for integration with other devices,an approved set of tests should be used.Due to the necessity to support only the interfaces provided by the particular RTA device, the number ofinstrumental computers in this testbench is usually small, and SSH systems are implemented in single-computerconfigurations. This enables composition of all testbench hardware, together with the RTA device, into a single rack.Sharing of hardware resources between testing and monitoring tools helps to keep hardware requirements low.A “unified” testbench for working with different RTA devices from a specified set is organized in a similar way.Instrumental computers of such testbench cover all types of external interfaces provided by devices from the set, innumbers sufficient for working with every single device from this set.The testbench can be used for testing and debugging of software on a partially equipped RTA device, for instance acentral computer with only some of processor and communication modules installed.

This approach is reasonable fordevelopment of particular subsystems of the RTA device software.2. Testbench for testing and debugging the software of several connected RTA devices. This testbench is intended forworkout of communication between two or several directly connected RTA devices, for instance the centralcomputer and a display device. The testbench can also be used for performing some activities of debugging thesoftware of these devices.

This testbench is similar by hardware structure to the one described above.Monitoring tools are used on this testbench to explore the communication between RTA devices comprising the RTAsubsystem under test.As in the previous case, it is possible to create a testbench intended for workout of different sets of RTA devices. Thecentral computer and one of several display devices from the DCS may serve as examples of such sets.Working out the inter-device communication between devices of an RTA subsystem is an intermediate step tointegration of the whole RTA system. Use of this testbench relieves the “main” RTA system integration testbenchfrom tasks of detecting and fixing the issues of co-operation between most intensely communicating devices.3. Testbench for RTA system integration and acceptance testing.

This testbench is intended for stepwise integrationof the whole RTA system, as well as for acceptance testing of the system. The testbench supplies test data to allexternal input interfaces of the RTA system and obtains the responses from all external output interfaces. In addition,monitoring of all inter-device channels must be supported.As it is required to work out the complete inter-device communication protocols, the testbench includes a largenumber of instrumental computers (5-6 and more, depending on the RTA system characteristics) and full scalemultiple-computer SSH systems.During the acceptance testing of an RTA system software version, an approved test set for this version is used.4. Testbench for development of testing scripts.

This is an auxiliary testbench used solely for test developmentpurposes. The testbench contains several workstations and a server connected by Ethernet network.Debugging of tests is performed on workstations using such features of the FT toolset as support for virtual onboardinterfaces and tests execution in user input expectation mode.10A FAMILY OF TESTBENCHES TO SUPPORT TESTING OF REAL-TIME AVIONICS SYSTEMS5.

Testbench for acceptance testing of series-produced RTA systems. This testbench is intended for performingacceptance tests for RTA system sets before their installation onboard the aircraft. Second purpose of this testbenchis diagnostics of RTA devices which are subject to reclamations. The instrumental hardware of this testbench isessentially the same as for the testbench for RTA system integration and acceptance testing.The testbench includes a completely tested “reference” set of RTA devices. On arrival of a device subject toreclamations, this device replaces the corresponding reference device, and a batch of tests is automatically executedto examine the device under question.