Hand-Held Force Magnifier for Surgical Instruments

We present a novel and relatively simple method for magnifying forces perceived by an operator using a tool. A sensor measures the force between the tip of a tool and its handle held by the operator’s fingers. These measurements are used to create a proportionally greater force between the handle and a brace attached to the operator’s hand, providing an enhanced perception of forces between the tip of the tool and a target. We have designed and tested a prototype that is completely hand-held and thus can be easily manipulated to a wide variety of locations and orientations. Preliminary psychophysical evaluation demonstrates that the device improves the ability to detect and differentiate between small forces at the tip of the tool. Magnifying forces in this manner may provide an improved ability to perform delicate surgical procedures, while preserving the flexibility of a hand-held instrument.