Your team is tasked with designing the torsion rod for Caterpillar’s new dozer (see figure 1). The torsion rod is rigidly fastened at one end inside the chassis and the connected to the road wheel arm at the other. The intermediate supports keep the torsion rod stable (i.e., frictionless supports), but do not prevent twisting of the rod between the two ends. The initial design calls for a 5-inch diameter solid A36 steel torsion rod. Your team must check the initial design and determine if it meets the economical/strength/serviceability requirements (see Table 1).Your team will dsign the torsion rod with the assigned material to meet the economical/strenth/servieability requirements (see Table 1). Note: the current torsion rod design is solid but, you are not limited to a solid shaft. A procedural/numbers check is possible only for the economical/strength/serviceability requirements for the current 5-inch diameter solid steel (A36) torsion rod.Requirements for deliverable:Introduction and assumptions.General approach: discuss the design procedure you developed and how you ensured that the design requirements were met. You should present equations for the maximum actual shear stress, the allowable shear stress, the angle of twist, phi, the thermal elongation/contraction and the cost of the torsion rods.Provide a table that presents the required design values for A992 material: Outside radius and inside radius in 0.1 inch increments, andle of twist in degrees, max shear stress in ksi and total cos for 10 torsion rods). Additionally,, discuss the advantages and disadvantages of larger diameter shafts vs smaller diameter shafts with respect to cost, shear stress, and angle of twist.Provide conclusions and recommendations.Assumptions:The yield strength in shear is 50% of the yield strenth of the material in tension. The dozer will weight 60 tons and the stated factor of safety (FS) for each material will handle the increased laoding due to maneuver over rough terrain. The maximum allowable andle of twist is 7degrees. The dozer will have 5 road wheels on each side of the dozer requireing a total of 10 torsion rods.Determine the most efficient design providing the outside and inside diameter for the lowest cost design for your team specific to A992 material and determine the most efficient design from all four materials providing the outside diameter and inside diameter for the material that provides the overall lowest cost design.
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