in fig1 a typical prior art index table and computer controlled robot installation is illustrated . the index table assembly includes a base 10 mounted upon a floor plate 12 . the index table 14 is rotatably mounted upon bearings , not shown , so as to have a vertical axis of rotation , and work pieces , jigs and fixtures , not shown , are mounted upon the table work supporting surface 16 . the index table is adapted to be rotated by an electric motor , not shown , and selectively indexed to desired rotational positions about its axis . the computer controlled robot generally indicated at 18 is mounted upon support bracket 20 affixed to the floor plate 12 . the robot includes a collar 22 rotatably mounted upon the bracket 20 , and the robot consists of a plurality of pivotally interconnected arms 24 and 26 , each arm being associated with an appropriate motive means , such as a servo motor , whereby the pivotal motion of an arm may be accurately controlled . the outermost arm 26 is provided with a tool generally indicated at 28 , which may consist of a cutting tool , drill , welding electrode , or similar device commonly employed with robotic machine tools . control of the robot 18 and the rotation of the index table 14 , is by means of the programmed computers 30 and 32 located on the floor plate 34 . in the aforedescribed prior art arrangement the fact that the robot supporting bracket 20 is mounted alongside the index table 14 requires that the floor plate 12 be of relatively large size to adequately support both the index table and the robot apparatus , and it will be appreciated that the movement of the robot tool over the surface of the index table is always in an extended relationship , and in view of the rotative nature of work mounted upon the index table it is necessary for the tool to move through a rotative pass when operating upon index table mounted work pieces . also , the presence of the bracket 20 adjacent the table 14 and the robot overhang , limit access to the table 14 . the basic inventive concepts of the invention are best appreciated from fig2 and 3 . in these figures the index table base is represented at 36 , and the index table assembly includes a rotative index table 38 having a horizontally disposed work supporting surface 40 . the index table 38 is rotated by an electric motor , as later described , and electrical means , and index means , sense and determine the rotative position of the index table 38 about its axis of rotation , which is usually vertically oriented . the index table 38 is provided with a circular central opening 42 concentric with the table axis of rotation , and the cylindrical column 44 extends through the table opening having a longitudinal axis concentric and coaxial with the table axis of rotation . the column 44 is supported on the base 36 by the anchor plate 45 . at its upper end 46 , the computer controlled robot 48 is affixed to the column , and the robot may consist of a plurality of pivotally interconnected arms identical to the robot 18 shown in fig1 . the robot 48 is mounted upon a collar 50 rotatably mounted on the column upper end for rotation by the motor 51 wherein the computer arms may rotate relative to the column . as it is necessary that electrical conductors supply and control the robot , and as such conductors and connectors extend through the hollow column 44 , the robot arms can rotate through substantially 300 ° of rotation on the column and the tool 52 is capable of covering an area on the index table as represented by the dotted lines 54 of fig3 . the robot 48 may be of any conventional type , and includes an arm 56 which pivots about a horizontal pivot , and is rotated about its pivot by electric servo motor means generally indicated at 58 . the arm 56 includes a vertical pivot from which the l - shaped arm 60 extends , and a servo motor 62 determines the angular relationship of the arm 60 to the arm 56 . the tool 52 is mounted on the free end of the arm 60 . any type of computer controlled robot may be mounted upon the column 44 , and the disclosed and described type is that such as manufactured by miller electric manufacturing mfg . co . of appleton , wis ., model mrh - 5 , as used for arc welding purposes . as will be appreciated from fig4 and 5 , the index table base includes bearing structure 66 , fig4 supporting the index table 38 for rotation about its vertical axis , and the base also includes index apparatus which is electrically controlled including a detent 68 selectively cooperating with holes or recesses 70 defined on the underside of the work piece index table 38 for fixing the rotative position of the index table relative to the base , as is well known . rotation of the index table is accomplished by the electric motor 72 driving the transmission 74 which in turn associates with the worm gear 76 engaging the worm wheel 78 concentrically affixed to the index table 38 thus , energization of the reversible electrical motor 72 will rotate the index table 38 in the desired direction as long as the detent 68 is not located in a recess 70 . the rotative position of the index table is sensed by a plurality of electrical sensors 80 mounted on the base 36 , fig4 and 5 , sensing indicators 82 mounted on the underside of the table 38 . the position of the indicators 82 and the position of the sensors 80 is such that a desired angular position of the index table will produce an electric signal to indicate a predetermined rotative index table position . control of the robot 48 , and the rotation of the index table 38 , is through the computer apparatus schematically shown in fig2 at 84 . the computer 84 may be located at some distance from the index table 38 , for instance in the corner of a room , and the usual feedback sensors and the like associated with the robot 48 and its motors 58 and 72 will permit the robot arms 56 and 60 to be positioned as desired . additionally , the index table motor 72 , and the index table sensors 80 , and the index detent 68 are electrically connected to the computer 84 wherein the operations of these components is computer controlled and coordinated with the desired robotic movements . accordingly , by the desired programming , as well known in the art , the rotation of the index table 38 and the movement of the robot arms , can be sequential or simultaneously operated , as programmed . typically , a plurality of work holding jigs or fixtures schematically shown in fig2 only , at 86 are mounted upon the index table surface 40 upon which work pieces 88 are clamped . an operator standing at one location adjacent the index table 38 may load and unload the fixtures as they pass his station , and as the index table is rotated about its axis of rotation the robot tool 64 will perform the desired operations on the work piece . the central mounting of the robot 48 relative to the index table 38 permits the tool 64 to &# 34 ; follow &# 34 ; the work piece as it rotates with the index table with a smooth continuous movement , and the tool can rotate &# 34 ; ahead &# 34 ; or &# 34 ; behind &# 34 ; the work piece with respect to its rotation due to the index table movement with a minimum of difficulty since both table and robot are rotating about the same axis . hence , the central mounting of the robot with respect to the index table permits a versatility and accuracy of positioning of the robot relative to a rotatable movable work piece no heretofore known , and the combination of the index table and centrally mounted robot permits robotic operations to be accomplished faster and more accurately than previously attainable with similar apparatus wherein the robot is mounted relative to the index table as shown in fig1 . furthermore , the apparatus incorporating the invention is more concise than the prior art apparatus requiring significantly less floor space , and providing much improved access to the index table work supporting surface throughout its circumference . modifications to the inventive concepts may be apparent to those skilled in the art without departing from the spirit and scope of the invention .