A COMPARISON OF THE MOBILITY NUMBER AND BEKKER APPROACHES TO TRACTION MECHANICS AND RECENT ADVANCES IN BOTH METHODS AT THE N.I.A.E

摘要

There are three main methods available to the engineer who seeks to predict the performance of off-road wheeled vehicles. The first is the use of formal methods of plasticity to define the soil failure zones ahead of and behind the wheel, and hence to calculate wheel forces. Closed form solutions are not possible with this method and digital computers must be used to obtain a solution. This results in a cumbersome analysis which is not, as yet, suitable for practical application. The second and third methods are the Bekker traction mechanics and empirical equations based on the wheel mobility number. The development of the last two methods are outlined in this paper, the relative advantages and disadvantages of the two methods compared and recent work at N.I.A.E. on both methods discussed.