This paper discusses the elements, techniques, and characteristics of a practical computer program developed for designing progressive traffic-signal-system timing plans. The elements discussed include directional travel distance variations, directional and sectional speed differences, band widths, offsets, cycle lengths, progressive speeds, and splits. The computer program, written in Fortran iv programming language, converts all speed and distance units to travel time units. The timing plan resulting in the greatest efficiencies is then determined from a time-travel time diagram. The program favours the directional band widths in proportion to the desired relative band widths and prints a series of tables which indicate, from the ranges specified for the numerous variable elements, the optimum timing plan.
Abstract