pivot 54 to the distal pivotal connection 53 compared to the distance from the pivot 54 to the proximate pivotal connection 56 is the same ratio as that of the mass of the voice coil magnet and reaction mass 48 to that of the mass of the voice coil 46 flexure 50 and spindle 44 combined the second end of the intermediate connection member 55 is connected to the last connection member 57 which is affixed to the voice coil 46 it is to be noted that the voice coil 46 and said voice coil magnet coupled to said reaction mass 48 each simultaneously move in opposite directions along the z axis since the mass of said voice coil 46 spindle 44 and said flexure 50 is less than a mass of said voice coil magnet coupled to said reaction mass 48 the amount of their linear movements are in proportion to their masses for example if the combined mass of the voice coil 46 spindle 44 and said flexure 50 is 100 grams and the combined mass of said voice coil magnet coupled to said reaction mass 48 is 1000 grams then the voice coil 46 spindle 44 and said flexure 50 will move 10 times further and in the opposite z axis direction than the voice coil magnet coupled to said reaction mass 48 will move the decoupled force frame metrology frame design in conjunction with the balanced reactionary force drill unit attempt to bring all of the net reactionary forces derived form the positioning and drilling functions of the.