Effect of initial lateral separation on droplet rheological behaviors (Co = 0.15, Ca = 0.14): (a) motion behaviors (y0/R1 = 1.57, k = 1, scale bar = 300 μm); (b) motion behaviors (y0/R1 = 1.23, k = 1, scale bar = 300 μm); (c) relative trajectory; (d) droplet deformation.