초록 ▼

A microprocessor-based interactive apparatus to compute coefficients of static and dynamic friction for a test surface using deceleration data of a weighted block sliding to a rest on the test surface. The apparatus provides an accessible graphical display of the recorded deceleration data which com

A microprocessor-based interactive apparatus to compute coefficients of static and dynamic friction for a test surface using deceleration data of a weighted block sliding to a rest on the test surface. The apparatus provides an accessible graphical display of the recorded deceleration data which comprises a series of relative time values and associated block acceleration values. A movable cursor permits the user to interactively select the point on the surface for which the coefficient of friction is to be computed. The computed coefficient is then displayed on the graphics display device with the deceleration plot. The cursor may then be redisplayed and moved horizontally with respect to the graphical plot of the deceleration data so that another coefficient of friction may be computed and displayed for a different selected point.

대표청구항 ▼

A method of determining the coefficient of dynamic friction of a surface, comprising: imparting an impulse to a block standing on the surface and having a bottom surface of a known test material, sensing the acceleration of the block at a series of times; generating a series of analog signals propor

A method of determining the coefficient of dynamic friction of a surface, comprising: imparting an impulse to a block standing on the surface and having a bottom surface of a known test material, sensing the acceleration of the block at a series of times; generating a series of analog signals proportional to the instantaneous acceleration of the block, each analog signal being generated at a separate such time; converting each analog signal to a digital signal; communicating the digital signals to a microprocessor; recording the value of each digital signal together with its respective time relative to initially imparting the impulse to the block; displaying a plot of acceleration against time using the recorded digital values and their respective times; selecting a time for which a coefficient of friction is to be computed; determining an average acceleration at the selected time by using a plurality of recorded digital values of acceleration following the selected time; computing the coefficient of friction by dividing the computed average acceleration by the acceleration of gravity; and displaying the computed coefficient of friction on the video display.