The alignment of the equatorial and orbital axes in the substellar regime and possible formation mechanisms that responsible for such alignment have received increasing attention in recent years (e.g., Harding et al. (2013a);Harding et al. (2013b);Dupuy et al. (2016) ). Prior to that, Many studies have shown the rotational evolution of interstellar clouds and the spin and orbital properties of solar-type binaries (Weis (1974);Abt and Levy (1976);Bodenheimer (1978);Fekel Jr (1981);Hale (1994);Albrecht et al. (2011)). (Hale (1994)) found the separation between solar-type binary components of 30-40 AU or less would have reasonable coplanarity with respect to orbit and equators. Similar to these studies, Weis (1974) showed the orthogonal alignment between rotation axes and orbital planes over a wider range of spectral classes B-F.On the other hand, the spin of close BH-NS binaries is significantly misaligned with respect to the orbital axis (Kalogera (2000)). studies by Jensen et al. (2004) suggested that disks in wide binaries (200 – 1000 AU)are aligned with each other within 20 degrees but not perfectly coplanar. In the case of an exoplanet, spin-orbit alignment of exoplanets system such Kepler-25c appears to be aligned with the stellar spin axis (Campante et al. (2016)). Thus, it appears that the spin-orbit alignment is common, since all
of the components are from the same region of a molecular cloud. However, there are exceptions at all orbital separations(Albrecht et al. (2011); Harding et al. (2013b)). Binaries are the key to understanding VLM dwarfs as they provide the rare opportunity to directly determine masses and provide necessary reference points for the direct calibration of models. VLM binary dynamical masses have been extensively studied via high-resolution adaptive optics (hereafter AO) imaging (Bouy et al. (2004); Bouy et al. (2008); Dupuy et al. (2010); Konopacky et al. (2010)), and references therein) and proved an invaluable resource in understanding the limitations of theoretical models. After that, Konopacky et al. (2012) measured v sin i for individual components of 11 very low mass (VLM) binaries with spectral types between M7.5 to L7.5, based on observations taken with the near-infrared spectrograph, and the Keck II laser guide star adaptive optics system. Rotational velocity is an important diagnostic parameter for stellar objects, offering a window into the angular momentum evolution of a given source. A star rotation can provide important clues to its formation and can furnish diagnostics of its interior structure and evolution. For instance, measurements of rotational velocity have been shown to correlate strongly with stellar activity, possibly driving the magnetic dynamo responsible for generating this activity (Browning (2008)). In addition, rotational velocities have been shown to correlate with the age of a system, offering a tool for estimating stellar ages (Delfosse et al. (1998)).