A control unit for a computer-assisted medical device comprising: one or more processors; and an interface configured to couple the control unit to a first input device (100, 230, 360, 520, 550, 555, 580); wherein the control unit is configured to: determine a reference point for the first input device (100, 230, 360, 520, 550, 555, 580); select a first virtual feedback model (410, 420, 430, 440) for the first input device (100, 230, 360, 520, 550, 555, 580) from among a plurality of VFMs (410, 420, 430, 440) for the first input device (100, 230, 360, 520, 550, 555, 580); configure one or more parameters of the first VFM (410, 420, 430, 440); determine a first position of the first input device (100, 230, 360, 520, 550, 555, 580) based on information from one or more first sensors associated with the first input device (100, 230, 360, 520, 550, 555, 580); determine a displacement between the first position and the reference point; determine a first feedback level for the first input device (100, 230, 360, 520, 550, 555, 580) based on the displacement and the first VFM (410, 420, 430, 440), wherein the first feedback level is zero until the displacement exceeds a threshold and the first feedback level is proportional to the displacement above the threshold; and send, based on the first feedback level, one or more first feedback commands to one or more first actuators associated with the first input device (100, 230, 360, 520, 550, 555, 580). one or more processors; and an interface configured to couple the control unit to a first input device (100, 230, 360, 520, 550, 555, 580); wherein the control unit is configured to: determine a reference point for the first input device (100, 230, 360, 520, 550, 555, 580); select a first virtual feedback model (410, 420, 430, 440) for the first input device (100, 230, 360, 520, 550, 555, 580) from among a plurality of VFMs (410, 420, 430, 440) for the first input device (100, 230, 360, 520, 550, 555, 580); configure one or more parameters of the first VFM (410, 420, 430, 440); determine a first position of the first input device (100, 230, 360, 520, 550, 555, 580) based on information from one or more first sensors associated with the first input device (100, 230, 360, 520, 550, 555, 580); determine a displacement between the first position and the reference point; determine a first feedback level for the first input device (100, 230, 360, 520, 550, 555, 580) based on the displacement and the first VFM (410, 420, 430, 440), wherein the first feedback level is zero until the displacement exceeds a threshold and the first feedback level is proportional to the displacement above the threshold; and send, based on the first feedback level, one or more first feedback commands to one or more first actuators associated with the first input device (100, 230, 360, 520, 550, 555, 580). determine a reference point for the first input device (100, 230, 360, 520, 550, 555, 580); select a first virtual feedback model (410, 420, 430, 440) for the first input device (100, 230, 360, 520, 550, 555, 580) from among a plurality of VFMs (410, 420, 430, 440) for the first input device (100, 230, 360, 520, 550, 555, 580); configure one or more parameters of the first VFM (410, 420, 430, 440); determine a first position of the first input device (100, 230, 360, 520, 550, 555, 580) based on information from one or more first sensors associated with the first input device (100, 230, 360, 520, 550, 555, 580); determine a displacement between the first position and the reference point; determine a first feedback level for the first input device (100, 230, 360, 520, 550, 555, 580) based on the displacement and the first VFM (410, 420, 430, 440), wherein the first feedback level is zero until the displacement exceeds a threshold and the first feedback level is proportional to the displacement above the threshold; and send, based on the first feedback level, one or more first feedback commands to one or more first actuators associated with the first input device (100, 230, 360, 520, 550, 555, 580).