Abstract: An apparatus includes a sample stage, a cantilever mount, a cantilever-force detector, a cantilever feedback system, and a sample stage feedback system. The sample stage is configured for holding a sample. The cantilever mount is configured for mechanically fixing a mechanical cantilever having a scanning tip. The cantilever-force detector is configured to produce an electrical cantilever-force error signal. The cantilever feedback system is configured to electromechanically drive the mechanical cantilever in a manner responsive to the cantilever-force error signal. The sample stage feedback system is configured to electromechanically displace the sample stage in a manner responsive to the cantilever-force error signal. The cantilever feedback system and the sample stage feedback system are connected to receive the cantilever-force error signal in parallel.