Method of Estimating the Volumetric Carrying Capacity of a Truck Body

Abstract

A method for estimating the effective volumetric capacity of a truck body includes establishing a side-to-side profile of a generic load model by extending load side lines upward at a predetermined material angle of repose from the upper edge of the side walls of the truck body and a front-to-rear profile by extending a front load line upward from the upper edge of the front wall and a rear load line upward from at or near a rear edge of the floor at the predetermined material angle of repose. Load plateau lines having predetermined dimensions are established and the height of the plateau lines is determined. A top profile of the generic load is then created and the shape of the load plateau is adjusted into a closed curve shape. A final three-dimensional generic load model is formed and the volume of load model is calculated.

1 . A method for estimating the volumetric capacity of a truck body having a pair of side walls, a front wall and a floor, comprising the steps of:
 (a) establishing a side-to-side profile of a generic load model by extending a load side line upward at a predetermined material angle of repose from the upper edge of each of the side walls of the truck body to a peak;   (b) replacing the peak of the generic load model side-to-side profile with an side-to-side load plateau profile line of a predetermined width while maintaining the load side lines at the predetermined material angle of repose;   (c) establishing a front-to-rear profile of a generic load model by extending a front load line upward from the upper edge of the front wall of the truck body at the predetermined material angle of repose and a rear load line upward from at or near a rear edge of the floor of the truck body to a peak;   (d) replacing the peak of the generic load model front-to-rear profile with a front-to-rear load plateau profile line of a predetermined length while maintaining the front and rear load lines at the predetermined material angle of repose;   (e) adjusting the final height of the load plateau profile line in the front-to-rear profile and side-to-side profile of the generic load to the lesser of the height of the load plateau profile line in the side-to-side profile as produced in step (b) and the height of the load plateau profile line in the front-to-rear profile as produced in step (d);   (f) creating a top, profile of the generic load from the side-to-side and front-to-rear profiles of the generic load produced in step (e), the top profile of the generic load having a polygonal-shaped load plateau;   (g) adjusting the shape of the load plateau by defining a final outer boundary of the load plateau as a dosed curve inscribed in the polygonal-shaped load plateau from step (f);   (h) contouring the side load lines produced in step (a) and the front and rear load lines produced in step (c) below the final outer boundary of the load plateau into a generally conically shaped surface in which the sides of the conical shaped surface are still inclined at the predetermined material angle of repose to form a final three-dimensional generic load model defined by the load plateau from step (g) and where the generally conical shaped surface intersects the side walls; front wall and floor of the truck body; and   (i) calculating the volume of the final three-dimensional generic load model.   
     
     
         2 . The method of  claim 1  wherein the predetermined width of the side-to-side profile of the load plateau line of step (b) equals the predetermined length of the front-to-rear profile of the load plateau line of step (d). 
     
     
         3 . The method of  claim 2  wherein the predetermined width and predetermined length equal 20% of the distance between the side walls of the truck body. 
     
     
         4 . The method of  claim 1  wherein the predetermined material angle of repose is 26.6.degree. 
     
     
         5 . The method of  claim 1  wherein the step of contouring the side load lines and the front and rear load lines comprises the steps of extending a plurality of contour lines downward at the predetermined material angle of repose at equal angular intervals around the final outer boundary of the load plateau until the contour lines intersect the truck body, extending contact lines between the points where adjacent pairs of contour lines intersect the truck body, and extending contour planes between each adjacent pair of the contour lines from the final boundary of the load plateau to the respective contact line. 
     
     
         6 . The method of  claim 1  wherein the load side lines in step (a) are extended upward from the upper inner edge of the side walls of the truck body. 
     
     
         7 . The method of  claim 1  further including the step of selecting the predetermined material angle of repose.