A PC-based data acquisition system supervisor for wind tunneltests

摘要

CIRA's "Instrumentation and Data Acquisition" group has developedan application software, working on a distributed environment, toautomate the repetitive wind tunnel tests and to control the dataacquisition process and visualise the data, from locations remote to thecontrol room. Pressure acquisition subsystems of the CIRA transonic windtunnel (PT-1) have been integrated, co-ordinated and controlled bysoftware modules running on different PCs operated by Windows 95/NT. Asoftware module called "Server", running on a local PC (Controller)which directly interacts with the electronic device through the relevanthardware interface, receives and sends messages for configuration &control. Each controller works as a server and export data by aDataSocket Server. A software module called "Integrator", running on aremote PC and connected to the controller PCs through a LAN link, worksas client of the different servers from which receives messagescontaining information about subsystems. The integrator co-ordinates theoperations of subsystem configuration, configuration upload,calibration, data acquisition, data recording and data visualization.The integrator can automate the entire process for pitch&pause orpitch sweep tests using a software mechanism to trigger the datarecording at the achievement of a specified condition configured by theoperator. The communication between client and servers is implemented bymeans of TCP/IP messages. One more module, called "Viewer", allows theuser to have a real-time display of the acquired data in the format heprefers: numerical display, time history or histogram (a way torepresent a group of channels simultaneously to show, for instance,pressure distributions). Different sets of data channels can be showedby different instances of the viewer running concurrently on the same PCor on different PCs located remotely to the data servers (customeroffices) and connected to the LAN