Design resolution

Design resolution is the theoretical smallest commanded movement implied by a positioning mechanism's drive components. For a screw drive, it can be calculated from screw pitch, reduction gearing and motor or encoder increments. It is not automatically the minimum incremental motion that the final load executes repeatedly.^[ref]

For an original ideal drive, let a lead screw advance $p=0.50\mathrm{mm}$ per revolution, with 50 motor revolutions per screw revolution and 2000 resolved counts per motor revolution. One count corresponds toDoubling the count resolution to 4000 per motor revolution gives theoretical $q=2.5\mathrm{nm}$ without changing the screw. That calculation does not halve friction or remove backlash. A controller may display both increments even if the load moves only after several such commands have accumulated.

Keep the location and counting convention of the feedback sensor explicit. Counts at a motor shaft, counts at a screw and directly measured load position are different observations. A gearbox can introduce compliance between them. Pair the design calculation with an independent motion test to establish operational performance. A smaller theoretical increment also does not by itself establish absolute positioning accuracy or a smaller measurement uncertainty.