Bio-mimetic fibrillar adhesives,inspired from geckos feet,rely on van der Waals forces to attach on various surfaces.Arrays of fibrils in the nano-meter scale can reach deeply into every corner of the contacting surfaces and create strong adhesion through summation of van der Waals forces at every contact point.To ensure a large number of fibrils hold grip on the contacting surfaces,geckos utilize a "Load-Drag-Pull"(LDP)sequence of movement to comb the hair of their feet onto the surfaces.The LDP movement inspired a measurement method that can be implemented with a scanning probe microscope.This method measures the shear-induced adhesion of the fibrillar adhesives and has been proven that the additional dragging movement increases the adhesion forces.In this article,we expand the investigation of shear induced adhesion of bio-mimetic fibrillar adhesives in different configurations,including different fibril lengths and surface treatments.The shear induced adhesion in twelve different configurations of fibrillar adhesives are measured using the scanning probe technique.Four types of samples are prepared in terms of fibril lengths,i.e.fibrils lengths at~0.1 m,~0.5 m,~1 m and~2.5 m.Fibril diameters are non-uniform but all in sub-micron size.In the surface treatment variations,the fibrillar adhesives are coated by silane molecules either with or without water in the coating process.Together with the fibrils treated with no surface modification,three types of fibrils are prepared in terms of surface treatments.Each of the 12 samples is measured at 4800 different locations using the LDP method by a scanning probe microscope.Large amount of experimental measurements enable statistical analysis of the trend among different sample types.The adhesion properties of such nano-fibrillar adhesive are studied thoroughly to enlighten future developments of bio-mimetic fibrillar adhesives and their use in different applications.