Development of Start Feel Index of a Forklift Truck

지게차 출발감각 평가지수 개발

  • Published : 2002.01.01


In this paper the start fuel index was developed to estimate ride quality of a forklift truck during the start motion. Through the consultation with test drivers, definition of start feel was made, and three parameters were selected to describe the start motion. They are engagement shock in the forwarding direction, vertical and pitch vibration respectively. To find out the relation between the measured motion and the subjective fueling, both the subjective rating and the measurement of vehicle motions were performed simultaneously. The correlation analysis between the two kinds of results showed start fuel was expressed by the measured accelerations with accuracy and reliability, Use of the new index has advantages of not only evaluating start fuel only by the measured signals but providing the consistent results which are not affected by physical and mental state of a test driver. Usefulness of the new index was confirmed by verification test on four new forklift trucks of a same model, which showed the order of preference by the index was coincided that by subjective evaluation.


Start Feel Index;Frequency Weighting;Subjective Rating;Psychophysical Law;Pitch and Bounce of a Vehicle


  1. Kozawa, Y., Sugimoto, G. and Suzuki, Y., 'A New Ride Comfort Meter,' SAE Technical Paper, No.86-430
  2. Smith, C. C., 1976, 'The Prediction of Passenger Riding Comfort from Acceleration Data,' Research Report 16, Department of Transportation, The University of Texas at Austin, 1976
  3. Guilford, J. P., 1954, Psychometric Methods, 2nd ed., McGraw-Hill
  4. Chen, C. T., 1999, Linear System Theory and Design, 3rd ed., Oxford University Press
  5. Stevens. S. S., 1986, Psychophysics: Introduction to Its Perceptual, Neural, and Social Prospects, New Brunswick
  6. Cucuz, S., 1994, 'Evaluation of Ride Comfort,' International Journal of Vehicle System Design, Vol. 15, No, 3/4/5, pp. 318-325
  7. International Organization for Standardization, 1997, Mechanical Vibration and Shock-Evaluation of Human Exposure to Whole-body Vibration, ISO 2631-1
  8. Ebe, K. and Griffin, M. J., 2000, 'Quantitative Prediction of Overall Seat Comfort,' Ergonomics, 43(6), pp. 791-806
  9. Braun, S. ed., 1986, Mechanical Signature Analysis-Theory and Application, Academic Press
  10. Ebe, K. and Griffin, M. J., 2000, 'Qualitative Models of Seat Discomfort Including Static and Dynamic Factors,' Ergonomics, 43(6), pp. 771-790
  11. Jang, H.-K. and Greffin, M. J., 'Effect of Discomfort Associated with Differential Vertical Vibration at the Seat and Feet,' Journal of Sound and Vibration, 229(9), pp. 273-286, 2000
  12. Jang, H.-K. and Griffin, M. J., 'The Effect of Phase of Differential Vertical Vibration at the Seat and Feet on Discomfort,' Journal of Sound and Vibration, 223(5), pp. 785-794, 1999
  13. Howarth, H. V. C. and Griffin, M. J., 1988, 'The Frequency Dependence of Subjective Reaction to Vertical and Horizontal Whole-Body Vibration at Low Magnetudes,' Journal of Acoustical Society of America, 83(4), pp. 1406-1413
  14. Daniel, W. W., 1990, Applied Nonparametric Statistics, 2nd ed., PWS-Kent Publishing Company
  15. Griffin, M. J. and Whitham, E. M., 1980, 'Discomfort Produced by Impulsive Whole-body Vibration,' Journal of Acoutical Society of America, 68(5), pp. 1277-1284
  16. Griffin, M.J., 1990, Handbook of Human Vibration, Academic Press