Abstract
A procedure for correction of calibration curves for creep of foam rubber in contact pressure measurement using a recently developed optical measurement system is presented. The critical part of this system is the foam rubber, which is placed between the tire and an illuminated glass plate. The image intensity of the contact area obtained from the system is directly related to the deformation of the foam rubber placed under the tire. Since the foam rubber used in this system is viscoelastic in nature, the pressure obtained using the calibration assuming no viscoelastic effect may give erroneous values. In the present study, an attempt is made to investigate the effect of creep of the foam rubber on the measurement of contact pressure and develop a procedure to correct the error that occurs due to creep in the foam rubber. An exponential model is proposed that demonstrates the viscoelastic deformation for the kind of loading that takes place in this application. An illustrative example is presented in which it is shown that the errors that occur due to delayed measurement could be as high as 10 percent.
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Chacko, S.R., Sivakumar, S.M. A procedure for correction of creep in foam rubber optical pressure measurement techniques. Experimental Mechanics 39, 125–131 (1999). https://doi.org/10.1007/BF02331115
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DOI: https://doi.org/10.1007/BF02331115