Body Orientation and Perceptual-Motor Performance

A number of investigations have been conducted on changes in controldisplay relations as factors affecting performance. Control-display relations refer to relations between changes of the control and corresponding changes of the display with reference to some coordinate system. Directional relations between control and display are thus a function of apparatus construction; the presence of the subject is not necessary for this description. The simplest way to describe spatial directional relations between control and display on the Toronto Complex Coordinator (TCC) ( 5 ) using an airplanetype stick control is to regard the control pivot as the centre of a fixed dock face, with the 12 o'dock position always pointing toward the display. In the 12 o'clock position, control-display directional relations are defined by saying that the movement of the stick toward 12 o'clock moves the display light up, and movement toward 3 o'clock moves the light to the right. With the clockface fixed, when the control-unit is rotated 90' clockwise, an upward movement of the display-light is now effected by a movement of the control-stick to the right (toward the 3 o'clock position), when rotated 180°, by a movement of the control-stick away from the display (toward the 6 o'clock position), and when rotated 270' by a movement of the control-stick to the left (toward the 9 o'dock position). Accordingly, the control-display directional relations may be stated by stating the clock-face number toward which a movement of the control-stick moves the light in an upward direction. Thus far, consideration has been given to a method of describing the relation between control and display. The same clock-face designation can be