Aerospace engineers run simulation tests over ISDN network to visualize and discuss experiments

Madrid, 02 November 98 Intensive interchange of concept design information, test results, and task distribution on an international basis between industrial aerospace companies, universities and aerospace research institutes still happens via phone calls, fax and mail transmissions, or physical meetings. In order to reduce time consuming, expensive travels and to organize work practices in a efficient way, the Spanish aerospace leader Casa has launched the Esprit funded ACATAD project within the CEPBA-TTN division for the development of advanced communications and computer supported collaborative work (CSCW) tools. Together with four other partners, Casa will perform three experiments of tele-testing and mechanical analysis to assess the impact of ISDN networked communication on the time- and cost-related aspects of commercial product design.

In order to establish Advanced Communications Applied to the field of Aerospace Development (ACATAD), first a network infrastructure has to be set up to interconnect the different partner sites by means of Integrated Services Digital Network (ISDN) lines, which deliver speeds up to 2 MBps, according to the individual needs. The central component consists of an ISDN router, installed at each site, to interlink the Local Area Networks (LAN) through the implementation of ISDN on the Wide Area Network (WAN) and of an Ethernet interface on the LAN side. This type of ISDN network provides the essential mechanisms for data encryption and security, including firewall features, as well as the possibility to work on heterogeneous computer platforms.

The experiments are performed via COVISE, the Collaborative Visualization and Simulation Environment, which acts as an integration platform for the partners to share applications and discuss simulation and test results. This distributed software environment has been developed at the Rechenzentrum Universität Stuttgart (RUS) to be run on the different Silicon Graphics (SGI) partner workstations, equipped with proprietary SGI InPerson audio- and videoconferencing tools and whiteboards. Project co-ordinator Casa has organized two testing cases to measure within three different experiments the impact of the advanced communications with integrated CSCW tools on the established working practices in the fields of mechanical analysis and tele-testing.

The first test of structural analysis will be realized between Casa and GTD, one of its subcontractors, which is based in Valencia as a specialist in engineering services. GTD has to provide finite element method calculations by means of the NASTRAN software programme on computer aided design (CAD) models and load cases, developed by Casa. Once the simulations are performed, the results are viewed and examined on the COVISE platform by both partners to see if any modifications or refinements have to be applied in a following rerun of the calculations. For this purpose, COVISE includes a special ReadNastran module to display variables in stress and force.

The second experiment relates to thermal analysis on Casa models with the THERMICA software package and is executed by subcontractor Envision, an engineering services company in Madrid. The resulting calculations have to be written in THERMICA-VIF format to be visualized by COVISE as colours mapped on the model's geometry. The data includes the various degrees of absorption, reflection, emission and transmission as well as the temperature distribution. The third experiment involves the tele-testing of data, retrieved from the DYNAWORKS database, that is developed by Intespace, a European research institute, headquartered in Toulouse.

The test data is produced via sensor inputs during various runs after which the values are mapped onto the geometrical model of the specimen in order to view the results. The last experiment differs from the first two tests in that it makes no use of results proceeding from simulation programmes. The implementation of a collaborative and computer supported working platform of the same kind as provided by the ACATAD project team allows the aerospace experts at the participating sites to facilitate research, testing and engineering activities. A similar scenario would be quite useful to the automotive industry too. The project has a duration of 15 months and will take an end in February 1999. More details are to be found on the ACATAD homepage.

Leslie Versweyveld