Techniques for controlling position of an end effector of a robotic device relative to a virtual constraint

A method of operating a system comprising a robotic device including an end effector and one or more joints to position the end effector in a plurality of degrees of freedom, a navigation system configured to track an actual position of the end effector, and one or more controllers configured to perform the steps of:

• identifying a condition wherein the actual position of the end effector has been constrained by a virtual constraint;
• determining a home position of the end effector, the home position is a position the end effector would be located without regard to the virtual constraint;
• evaluating an anticipated movement of the end effector from the actual position to the home position;
• detecting that the anticipated movement would cause an anticipated collision between the end effector and the virtual constraint;
• computing a target position of the end effector that evades the anticipated collision, wherein the target position is spaced apart from the actual position and located along the virtual constraint;
• and
• controlling the one or more joints of the robotic device to slide the end effector from the actual position to target position along the virtual constraint.