the rotor shaft assembly consists of a bearing mounted shaft 484 a frameless motor rotor 486 and a harmonic drive wave generator 488 all rigidly connected as an assembly the second structural assembly consists of a harmonic drive rigid spline 490 a slip clutch assembly shown generally at 492 and a second outer tube 493 also attached to the second structural assembly in the preferred embodiment are a wire tube disk 494 and a wire passage tube 496 the pitch joint of fig1 operates in the following manner when the frameless motor stator 478 is energized the rotor shaft assembly which consists of items 484 486 and 488 as well as portions of the brake assembly explained below rotate within the confines of bearing 482 and wave generator 488 because the harmonic drive flexspline 480 is rigidly affixed to the first outer tube 474 via the torque bridge 479 the rotation of the wave generator 488 forces rotation of the rigid spline 490 relative to the first structural assembly the rotational motion of the rigid spline 490 is transmitted via a slip clutch to the second structural assembly through the slip clutch assembly 492 thus causing rotation of the slip clutch assembly 492 the second outer.