Simultaneous positioning and operation of multiple probe drives for inverse mirror experimental plasma device

An innovative instrumentation technique is developed to enable precise and efficient positional scans with motorized probe diagnostics, distributed axially and radially in Inverse Mirror Plasma Experimental Device (IMPED). The developed system automates diagnostic operations by positioning the probes, triggering the conditioning circuits, and acquiring and archiving structured data. A client-server based architecture is implemented and structured into discrete hierarchical layers enabling efficient remote operation and control over the Ethernet network. At the top layer, a supervisory node integrates multiple diagnostic probe drive units distributed over the local area network and implements positional scans using a programmatic input table in integration with the data acquisition system. The intermediate layer consists of embedded Transmission Control Protocol server nodes developed for each probe drive overseeing drive status, trajectory execution, and fault-tolerant operation. This layer communicates using the Standard Commands for Programmable Instruments, which are integrated through distributed embedded nodes. The bottom layer involves real-time servo controllers executing precise probe drive motion in closed loop control. The developed control technique of positional scan allows experiments with a user-defined extensive range of spatial locations with sub-millimeter precision (±0.2 mm). This system presently integrates 12 distributed motorized probe drives, allowing for simultaneous spatial positioning. For IMPED, a typical radial scan of 80 mm with 40 uniform steps is executed in ∼150 s. This automation enhances the reproducibility and efficiency of machine operation by significantly reducing the diagnostic time compared to manual operation. Scalability and flexibility of the architecture allow for future expansion, making it adaptable to similar scientific experiments.