1459839929-4cc4f820-40f5-4d0e-9a7b-b7e4f07c9338

Methods and apparatus for providing an adjustable balancing force are provided. The surface of the bearing pad can have two sides or four sides, can have spacing within the surface, or can be solid. The apparatus can switch optionally or automatically the above first, second and third modes and interactively designate the region to which the dodging processing is applied or the region to which the dodging processing is applied in the different intensity.