SAE BAJA PROJECT FRAME DESIGN Robert Golmon Advisor

SAE BAJA PROJECT FRAME DESIGN Robert Golmon Advisor: Dr. Lee Instructor: Cris Koutsougeras Et 494 - Senior Design Fall 2012

Introduction The Baja SAE project is a competition that simulates real-world engineering design projects and their related challenges. Engineering students are given the task to design and build an offroad vehicle that will survive the severe punishment of rough terrain.

Objectives The objective of my part of the baja project is to design and construct the chassis/frame of the vehicle from the ground up. Some challenges to are I need to keep the frame both light and strong while I try to keep the cost down. I will need to calculate the proper frame diameter and test the whole design by doing a stress analysis.

INVENTOR 2011 • To draw my frame I decided to use Inventor professional 2011. • Similar to auto cad but also has a FEM(finite element method) software built

Fall 2012 Add to my design by adding suspension mounts and other suspension components, using approved steering design. • Run stress analysis with FEM software on the new frame assembly. • After the design is approve I will need to build the frame •

Rear Suspension Design Four link suspension uses links to prevent the axle from moving side to side or back or forth while allowing it to go up and down as well as articulate. A well designed and tested four link will provide a superior translation to the ground and higher ride quality.

Four Link Design

Frame Analysis • For the analysis the weight of the driver an the weight of the engine were added where they connect to the frame. • I ran the analysis on different tubing sizes ranging from 1 x. 133 - 1. 25 x. 065 to find the smallest diameter pipe that would satisfy the max stress for the design factor.

Design Factor

Results Name � Minimum Maximum 0. 000 in 0. 014 in Displacement The tubing that satisfied the conditions and gave use the most weigh advantage was the 1. 25 x. 065 Sy/8. 7= 30043. 54/8. 7= 3453. 28 psi Displacement Forces � Fx -167. 671 lbforce 167. 330 lbforce Fy -25. 769 lbforce 26. 240 lbforce Fz -72. 074 lbforce 210. 373 lbforce Mx -163. 865 lbforce 169. 013 lbforce in in My -690. 276 lbforce 214. 525 lbforce in in Mz -56. 091 lbforce in 56. 071 lbforce in Smax -78. 571 psi 2983. 580 psi Smin -2759. 543 psi 723. 430 psi Smax(Mx) 0. 000 psi 1869. 558 psi Smin(Mx) -1869. 558 psi -0. 000 psi Smax(My) 0. 000 psi 2372. 986 psi Smin(My) -2372. 986 psi -0. 000 psi Saxial -247. 848 psi 723. 430 psi Normal Stresses

Final Frame Design • Material = 1020 Dom 1. 25 x. 065 tubing • Weight = 78. 7 lbs using 96 ft of tubing • Cost=$186. 24

Timeline September 12 - Proposal October 1 - have the altered design in cad October 27 - have the stress analysis for the new design December 1 – Constructed frame