is consistently assigned to pincher movement in all orientations in this embodiment the forward pointing orientation is the only one in which joystick motions are not assigned to the robot 39 s x y and z motion control in any of the other five orientations an operator can move the robot arm in a direction by displacing the joystick in that direction thus xyz translational motions are rendered completely intuitive by the present invention in order to prevent assignment oscillations when pendant 11 is moved about an oblique orientation pendant 11 or alternatively interface 15 is provided with a low pass filter and schmitt trigger or some other digital or analog filtering means the present invention provides for innumerable variations the use of two mercury vial switches permits four pendant orientations to be distinguished the use of the three mercury vial switches as in the illustrated embodiment permits all six faces to be distinguished by the interface the present invention is compatible with a variety of controller types including basic two axis joysticks joysticks with rotation as used in the illustrated pendant 11 joysticks with vertical displacement and trackballs force sensing joysticks are provided for as a special case of displacement sensing joysticks since inevitably there is some joystick displacement when force is applied in simpler applications the controller could be a one dimensional slider or spring loaded wheel its function being assignable by controller reorientation the means for sensing orientation can be varied as can the external frame of reference for example the frame of reference could be inertial space with.