Apparatus and related methods for assisting tool use includes one or more motors, a wrist support and a shaft coupled to the one or more motors. The shaft includes a coupling to couple to a tool to enable a user resting a hand with the wrist on the wrist support to hold and manipulate the tool with one or more fingers. The apparatus can include a controller configured to: receive position data indicative of a position of an active end of the tool； receive constraint data indicative of one or more regions of space in which the active end should not be positioned； and process the position and constraint data to control the one or more motors to bias the active end out of a region indicated by the constraint data when a position indicated by the position data is within the region indicated by the constraint data.
