Design and implementation of an upgraded electrical control system for the Vainu Bappu Telescope hydraulic platform

Abstract

This paper details the design, fabrication, and performance evaluation of a newly implemented hydraulic control system for the 2.3m Vainu Bappu Telescope (VBT) Cassegrain platform. The hydraulic platform is a critical infrastructure component used for instrument integration, maintenance during focal-mode transitions (Prime to Cassegrain), and providing observer access to the Cassegrain focus. The system architecture integrates 20 HP induction motors coupled with high-pressure oil pumps, a centralized reservoir, and solenoid-actuated control valves. Central to the upgrade is a custom engineered control panel featuring robust safety interlock logic to govern the vertical displacement of the platform. Following an expedited four-day fabrication and verification phase in October 2023, the system was commissioned and integrated into the VBT hydraulic pump room. Operational data collected from October 2023 through February 2026 demonstrates high system availability and reliability. The platform has supported critical telescope operations, including mirror re-aluminization and frequent instrument swaps, without functional failure. This longitudinal performance validates the control logic and hardware selection for heavy-duty astronomical support systems.