plots the three dimentional of grasping.
usage: grasp(input1,input2, dist1, dist2) % indicates the plotting of
grasp based on four arguments.
arguments: (input)
input1 - unsigned integer number for linspacing through x_axis.
input2 - unsigned integer number for linspacing through y_axis.
dist1 - the first distance for mesh. The input must be an integer.
dist2 - the second distance for mesh. The input must be an integer.
DEFAULT: dist2=0;