The adaptive optics (AO) technology unfolds the capabilities of ground-based telescopes and opens new horizons. A cost-effective and resilient laser-guided single conjugated adaptive optics system offers the opportunity to a significant number of existing 1-4 meter telescopes. This opens the door for medium-sized telescopes to pursue cutting-edge scientific research that may be challenging to achieve with larger observatories due to a scarcity of time for various survey observations. The medium-class telescope, equipped with adaptive optics along with advanced image processing, provides unprecedented image quality in terms of spatial resolution (sub-arcsec), high cadence with high SNR.

Here, we present a robust Rayleigh scattered laser-guided single conjugated adaptive optics system called SALTO, which was designed, built, and tested in the Belgian countryside on a 1-meter class telescope and an automated robotic adaptive optics system called iRobo-AO for IUCAA 2m telescope. These projects aim to demonstrate the possibility of rejuvenating the scientific goals of medium-class telescopes with AO technology. This talk discusses the overall study of the design of the AO system, from the optics to the control system. It also includes a description of the integration and calibration of SALTO along with successful on-sky results at 1.55µm under 2-3'' seeing. We also present our recent work on non-common path aberration correction at the Subaru telescope and high-spectral resolution interferometry BIFROST/Asgard instrument. The Asgard instrument suite is being designed as a guest instrument for the VLTI, representing a new generation of instruments that leverage long-baseline interferometry to perform spectroscopy and nulling.