초록 ▼

A surface roughness measuring method and apparatus for use in rail corrugations. The apparatus utilizes non-inertial sensors coupled to an on-board, real-time data processing unit. The method includes spacing a plurality of sensors along the surface at predetermined distances apart from one another,

A surface roughness measuring method and apparatus for use in rail corrugations. The apparatus utilizes non-inertial sensors coupled to an on-board, real-time data processing unit. The method includes spacing a plurality of sensors along the surface at predetermined distances apart from one another, relatively moving the sensors and the surface, sampling data from the sensors at fixed sample distance intervals L, storing data from the sensors measured over a region of the surface, converting the data into second finite difference data over the region, converting the second finite difference data into data representative of a space curve of the surface, and displaying the space curve representative data to provide an indication of surface roughness.

대표청구항 ▼

A method of measuring surface roughness comprising the steps of: (a) spacing a plurality of sensors along said surface at predetermined distances apart from one another, each of said sensors generating sensor-surface distance data, said spacing sleected such that the response characteristic of said

A method of measuring surface roughness comprising the steps of: (a) spacing a plurality of sensors along said surface at predetermined distances apart from one another, each of said sensors generating sensor-surface distance data, said spacing sleected such that the response characteristic of said plurality of sensors is non-zero for all wavelengths of surface roughness in excess of a predetermined folding wavelength, (b) relatively moving said sensors and said surface, (c) while relatively moving said sensors, sampling data from sensors at fixed sample distance intervals L, (d) storing data from said sensors measured over a region of said surface, (e) converting said data into second finite difference data over said region, (f) converting said second finite difference data into data representative of a space curve of said surface, and (g) displaying said space curve representative data to provide an indication of surface roughness. Apparatus for measuring surface roughness comprising: (a) a support, (b) at least two sensors coupled to said support, (c) means for relatively moving said support and surface to thereby move said sensors longitudinally along said surface, (d) means for sampling data outputs from said sensors at longitudinal distance intervals L, (e) said sensors responsive to surface roughness by measuring the component relative displacement of said sensors and surface in a direction perpendicular to said longitudinal relative motion direction, (f) means for coupling said sensors to said surface to enable said sensors to respond to said component relative displacement at first, second, third and fourth points spaced longitudinally along the direction of longitudinal relative motion, (g) said first and second points spaced apart by a distance mL, said second and third points spaced apart by a distance nL, and said third and fourth points spaced apart by a distance mL, m and n being integers having no common factors, (h) data processing means for processing said data outputs, said data processing means comprising a programmable digital computer operable for: (i) weighing data outputs of said sensors to form a first asymmetric cord offset (ACO) measurement defined by the point displacements m, n corresponding to a first ACO configuration for said first, second and third points, (ii) weighing data outputs of said sensors to form a second ACO measurement defined by the point displacements m, n corresponding to a second ACO configuration for said second, third and fourth points, said first and second ACO configurations being mirror images of one another about a plane midway between said second and third points, said first and second ACO measurements being insensitive to rigid body motion of said support, (iii) combining said first and second ACO measurements to form a first mid-cord offset (MCO) measurement corresponding to hypothetical points having relative displacements defined by m=n=1, and (iv) converting said first MCO measurement into data representative of a space curve of said surface, and (i) means for displaying said space curve representative data to provide a measure of surface roughness.