An actuator having electronically controllable tactile responsiveness which is flexibly programmable to facilitate provision in a single actuator of torque-position characteristics, such as a selectable number of detents per actuation through its full operative path. A rotary actuator facilitates provision in a single actuator, of torque versus angular position characteristics, such as a selectable number of detents per revolution. The actuator is in communication with a servo motor having a position encoder which outputs position information to a controller that has access to torque-position relation information. The controller outputs a digital torque signal, in accordance with the torque-position relation information, which is converted to an analog current signal applied to the servo motor to generate torque in the servo motor. The torque, presenting a tactile response to a human interacting with the actuator, is sensed as a detent or a plurality of detents. Similarly, an exercise machine actuator and a linear/joystick actuator are implemented having controllable tactile responsiveness that is electronically controllable in accordance with a selectable torque profile.