CONCLUSION 



173 



case, the same methods of evaluation may 

 be used. Experienced operators, represent- 

 ing a fair sample of the population that uses 

 the equipment, should be studied by means 

 of the time and motion techniques of micro- 

 motion analysis, eye movement recording, 

 opinion survey, etc. Up to the present time, 

 these procedures have been applied with 

 some success to the evaluation of aircraft 

 cockpits (7) and radar consoles (24, 34) but 

 their use should be extended to other types 

 of equipment. 



Usually only minor changes can be intro- 

 duced in current equipment without getting 

 into the problem of complete redesign. But 

 wherever possible, they should be made, and 

 then the equipment should be re-evaluated 

 for efficiency of operation. In cases where 

 changes are not feasible, it may be possible to 

 recommend changes in the training of op- 

 erators or changes in the procedures they 

 follow in working the equipment. For ex- 

 ample, one study has shown that the cockpit 

 of the DC 4 is poorly arranged for the exist- 

 ing procedures of checking out the instru- 

 ments and controls before take-off (7). It 

 was pointed out that this difficulty could be 

 rectified by changing the sequence in which 

 the pilot makes his checks (Fig. 10). In 

 another case, it was suggested that the ac- 

 curacy of reaching for controls in the cockpit 

 could be improved without redesign of equip- 

 ment by training pilots in "bhnd reaching." 



Conclusion 



From the foregoing discussion, it is appar- 

 ent that more research is needed on problems 

 of panel layout. At the present time, a good 

 start has been made toward specifying hu- 

 man requirements in the design of panels. 

 General principles and some quantitative 

 data are available on six major aspects of 

 panel layout: (1) the practical limits of the 

 working area, including the position of the 

 operator and the orientation of the panel, (2) 

 the optimal location of controls and displays, 

 (3) the importance and frequency of use of 

 controls and displays, (4) the patterning of 



controls and displays, (5) the distribution of 

 work over the body parts, and (6) the con- 

 fusion of controls and of displays. It should 

 be remembered, however, that the research 

 to date represents only a start in the solution 

 of practical problems. Psychological experi- 

 ments must be able to give the design en- 

 gineer complete quantitative data on hu- 

 man performance as a function of all the 

 important factors in panel layout. Further- 

 more, since it is unUkely that we will be able 

 to design equipment panels that incorporate 

 the optimal specifications for all factors at 

 once, it is of practical importance to know, in 

 each case, how performance varies over a 

 wide range of conditions deviating from some 

 optimal design or arrangement. Only then 

 will it be possible to design equipment in 

 keeping with the self-evident principle that 

 performance is a joint function of all the 

 factors in panel layout. 



Of equal importance with the study of 

 human capacity is the investigation of the 

 problems involved in the practical apphca- 

 tion of research knowledge to panel design 

 problems. The basic problem here is the 

 development of techniques for measuring 

 and evaluating human performance in com- 

 plex man-machine situations. Some head- 

 way has been made in adapting the time 

 and motion techniques of industry for meas- 

 uring performance on certain kinds of equip- 

 ment. But this work must be extended to 

 other types of equipment, and new tech- 

 niques must be developed if all the major 

 aspects of human performance are to be as- 

 sessed. The importance of developing valid 

 criteria and methods for evaluating the suita- 

 bihty of panel layouts in terms of the effi- 

 ciency of human performance cannot be 

 overemphasized. Without adequate evalua- 

 tion techniques, the successful appUcation of 

 research knowledge to practical equipment 

 problems is virtually impossible. 



References 



1. Barnes, R. M. Motion and time study. 

 New York: John Wiley, 1940. 



