VSRs

VSR is an acronym used in multiple fields. In security and video technology, VSR stands for Video Surveillance Recorder, a device that records video from surveillance cameras for storage and playback. VSRs may be standalone units, or integrated into a network video recorder (NVR) or digital video recorder (DVR) system. They support analog or IP cameras, retain footage on local drives or network storage, and provide features such as time stamping, search by time or event, and remote viewing.

In control theory and systems engineering, VSR can denote Variable Structure Regulator (or Variable Structure System), a class of controllers based on switching between different system structures to maintain stability and performance in the presence of uncertainties. Typical implementations involve sliding-mode control, designed to achieve robustness against parameter variation and disturbances. Challenges include chattering and implementation complexity; designers address these with boundary layers, higher-order sliding modes, or smoothing strategies.

Other uses include Very Small Reactor in energy discussions, referring to compact modular reactors, sometimes called very small reactors. In other domains, VSR can stand for different phrases; the meaning depends on context.