CWU RC Baja
Steering and Suspension
Fall Presentation
Winter Presentation
Spring Presentation
Engineering Report
Alternate design 1
Figure 1. First Design of front suspension and steering. Utilizes Single axle suspension and electric servo.
Alternate design 2
Figure 2. Second design of front and rear suspension, utilizes solid rear axle with trailing arms; as well as independent front suspension with an electronic servo.
Initial Idea
Figure 3. View of finished and assembled vehicle.
Intro:
The purpose of this website is to share the design, analysis, manufacturing, budget, schedule, and results of the engineering project. The objective of this project was to create a remote-controlled car that was capable of performing well in a variety of circumstances. Three competitions that were tested at the end were straight line racing, slalom racing, and a Baja course race. The scope for this half of the project was suspension and steering, another engineer was in charge of drivetrain and chassis. The suspension and steering consisted of three smaller complex systems; These systems were the front independent suspension, rear solid axle suspension, and the front steering system.
An engineers job is to apply knowledge of math, physics, and materials to solve problems. This project is nothing short of an engineering problem. The engineers in charge of this project not only designed the complex systems that made the car work properly, but they also did an analysis for each component. The engineer in charge of suspension and steering ensured that the bulkhead pin holes wouldn’t break under shear or that the tie rods wouldn’t buckle or bend when the car suspension absorbs various terrain these two specific analyses were done using statics and mechanics of materials. Many more analyses were done that involved dynamics, statics, mechanics of materials, kinematics, and fatigue analysis.
Results:
Table H1 Testing resutls
Above are the results from each test the engineer performed. The device passed both deflection tests and failed the shock compression test after a 2-foot drop. More information can be found below
Table H2 Drop test shock compression results
The table above shows the results from the drop test. As shown on the testing page each shock bottomed out after the drops. Therefore the shock compression was set to a maximum for each trial. This meant that the device failed this test, to remedy the issue the engineer had to order stiffer shock springs.
Figure 21 Force vs Deflection graph for lower control arm
The graph above shows the deflection of the lower front control arms after loads up to 175lbs were applied. The requirement was that the control arm deflected less than 0.0625" after a 20lb load was applied. In actuality the control arm only deflected 0.02" after a 175lb load, there for this test was a success.
Figure 22 Force vs deflection for rear trailing arm
The graph above shows the force vs deflection graph for the rear trailing arms. The trailing arms were required to deflect less than 0.0625" under a 8.5lb load. The test shows that the trailing arm only deflected 0.0624" under a 253.5lb load. Therefore this test was a pass.