REPRESENTATION OF THE HUMAN OPERATOR AS A SAMPLED-DATA SYSTEM

AN EXPERIMENTAL AND THEORETICAL INVESTIGATION IS DESCRIBED WHICH LED TO THE FORMULATION OF A SAMPLED-DATA MODEL THAT ACCURATELY SIMULATES THE CHARACTERISTICS OF THE HUMAN OPERATOR IN A COMPENSATORY TRACKING TASK. THE TASK ACTUALLY STUDIED WAS RESTRICTED TO VISUAL SENSING OF ERROR AND MANUAL OUTPUT BY HORIZONTAL MOVEMENT OF A VERTICAL CONTROL LEVER. ERROR WAS DISPLAYED TO THE OPERATOR AS A PROPORTIONAL HORIZONTAL DISPLACEMENT OF A VERTICAL LINE ON A C. R. T. , AND HIS TASK WAS TO KEEP THIS LINE AS CLOSE AS POSSIBLE TO A CENTRAL ZERO-REFERENCE POINT, I. E. , TO TRACK THE INPUT WITH THE SMALLEST POSSIBLE ERROR. STUDY OF THE DISPLAY INDICATED THAT THE OPERATOR ACTED UPON SAMPLES OF POSITION AND VELOCITY ERROR TAKEN AT INTERVALS OF APPROXIMATELY 0.15S. THE NATURE OF THE OPERATORS' RESPONSES TO STEP AND RAMP INPUTS WAS IN ACCORD WITH THIS HYPOTHESIS AND LED TO THE INITIAL FORMULATION OF A SAMPLED-DATA MODEL. COMPARISON OF THE RESPONSES OF OPERATORS WITH THOSE OF THE MODEL IN A CONTINUOUS TRACKING TASK REVEALED SOME DEFICIENCIES AND THE MODEL WAS ELABORATED BY INCORPORATING FEEDBACKS TO SIMULATE MORE SOPHISTICATED PREDICTION. IT WAS CONCLUDED THAT, IN THE TASK STUDIED, THE BEHAVIOR OF THE HUMAN OPERATOR COULD BE CHARACTERIZED BY A RANDOM SAMPLING OF BOTH POSITION AND VELOCITY, FOLLOWED BY A COMPUTATION OF REQUIRED FUTURE HAND MOVEMENT (ACCORDING TO SOME OPTIMAL STRATEGY) DURING THE SUCCEEDING SAMPLING INTERVAL AND ITS SUBSEQUENT EXECUTION OVER THE NEXT SAMPLING INTERVAL. /AUTHOR/

• Supplemental Notes:
  • Vol 115, pp 342-354
• Corporate Authors:

  Iee Proceedings /UK

  ,    
• Authors:
  • Lange, G W
• Publication Date: 1968-2

Subject/Index Terms

• TRT Terms: Human beings; Information systems; Mathematical models; Operators (Persons); Randomization; Samples; Sampling; Tracking systems
• Uncontrolled Terms: Models; Operator
• Old TRIS Terms: Data systems; Tracking models
• Subject Areas: Data and Information Technology; Highways; Safety and Human Factors;

Filing Info

• Accession Number: 00222858
• Record Type: Publication
• Source Agency: Traffic Systems Reviews & Abstracts
• Files: TRIS
• Created Date: Sep 30 1994 12:00AM