A surgical system (50, 124) comprising: a surgical manipulator configured to support a surgical instrument and an energy applicator extending from the surgical instrument; at least one controller configured to: operate the surgical manipulator in a manual mode, in which the surgical manipulator responds to forces and/or torques a practitioner places on the surgical instrument to position the surgical instrument, or a semi-autonomous mode, in which the manipulator calculates the forces and torques necessary to move the surgical instrument along a predetermined tool path of travel; implement a feed rate calculator to calculate an instrument feed rate, wherein the instrument feed rate is a velocity at which a distal end of the energy applicator advances along a path segment of the predetermined tool path in the semi-autonomous mode and wherein the feed rate calculator calculates the instrument feed rate by adjusting a defined feed rate, being a primary input into the feed rate calculator; implement a force overrider to compare forces and/or torques applied to or output by the surgical instrument and/or energy applicator to a lower limit level and a higher limit level, and, when the lower limit is exceeded, implement the force overrider to generate a signal and output the signal to deactivate the surgical instrument and stop the advancement of the surgical instrument, and implement the feed rate calculator to adjust the defined feed rate based on the signal from the force overrider so that the instrument feed rate is zero, and when the higher limit level is exceeded, implement the force overrider to generate a signal and output the signal to transition the surgical manipulator from the semi-autonomous mode to the manual mode. a surgical manipulator configured to support a surgical instrument and an energy applicator extending from the surgical instrument; at least one controller configured to: operate the surgical manipulator in a manual mode, in which the surgical manipulator responds to forces and/or torques a practitioner places on the surgical instrument to position the surgical instrument, or a semi-autonomous mode, in which the manipulator calculates the forces and torques necessary to move the surgical instrument along a predetermined tool path of travel; implement a feed rate calculator to calculate an instrument feed rate, wherein the instrument feed rate is a velocity at which a distal end of the energy applicator advances along a path segment of the predetermined tool path in the semi-autonomous mode and wherein the feed rate calculator calculates the instrument feed rate by adjusting a defined feed rate, being a primary input into the feed rate calculator; implement a force overrider to compare forces and/or torques applied to or output by the surgical instrument and/or energy applicator to a lower limit level and a higher limit level, and, when the lower limit is exceeded, implement the force overrider to generate a signal and output the signal to deactivate the surgical instrument and stop the advancement of the surgical instrument, and implement the feed rate calculator to adjust the defined feed rate based on the signal from the force overrider so that the instrument feed rate is zero, and when the higher limit level is exceeded, implement the force overrider to generate a signal and output the signal to transition the surgical manipulator from the semi-autonomous mode to the manual mode. operate the surgical manipulator in a manual mode, in which the surgical manipulator responds to forces and/or torques a practitioner places on the surgical instrument to position the surgical instrument, or a semi-autonomous mode, in which the manipulator calculates the forces and torques necessary to move the surgical instrument along a predetermined tool path of travel; implement a feed rate calculator to calculate an instrument feed rate, wherein the instrument feed rate is a velocity at which a distal end of the energy applicator advances along a path segment of the predetermined tool path in the semi-autonomous mode and wherein the feed rate calculator calculates the instrument feed rate by adjusting a defined feed rate, being a primary input into the feed rate calculator; implement a force overrider to compare forces and/or torques applied to or output by the surgical instrument and/or energy applicator to a lower limit level and a higher limit level, and, when the lower limit is exceeded, implement the force overrider to generate a signal and output the signal to deactivate the surgical instrument and stop the advancement of the surgical instrument, and implement the feed rate calculator to adjust the defined feed rate based on the signal from the force overrider so that the instrument feed rate is zero, and when the higher limit level is exceeded, implement the force overrider to generate a signal and output the signal to transition the surgical manipulator from the semi-autonomous mode to the manual mode.