1. STEERING SYSTEM for MINI BAJA CAR
Benjamin Genre
Advisor: Dr. Ho-Hoon Lee
Dr. Cris Koutsougeras
ET 493 Senior Design Project II
Fall 2017

2. Goals of Project
Construct a steering system for a mini baja car whose design lowers steering error.
Acquire and assemble parts in the most cost effective way.
Test and record results.

3. Importance of Steering Design
Proper steering design aids in comfort of the driver.
It helps to reduce skidding and wear on the tires
Normally follow the Ackerman Steering Principle

4. Ackerman Steering Principle
States that the axial lines of all the wheels should meet at the same point.

5. Steering Error
When the projections of the two front wheels do not meet at the same point on the rear axle’s axis.
Steering error will occur with the use of commercial parts.
Ackermann Steering Error

6. By changing the distance from the front axle to the rack, the steering error also changes.
The distance from the front axle to the placement of the rack-and-pinion is the main design point.
Rack and Pinion System

7. Background
Last semester a c-program capable of calculating steering error was created.
There were two frame design teams, so the program helped by allowing quick and flexible calculations.

8. Flow Chart Program made with Microsoft Visual Studio.
At the start of the program, the user is asked to input the constants of the design. These include:
Length from front axle to rear axle.
Width of car.
Length of the rack and pinion.
Length of steering arm.
Angle between steering arm and wheel.
Maximum displacement of rack.
Initial value of S (the distance between the front axle and rack.)
Maximum value of S.

9. Flow Chart Everything is calculated as a function of S.
Prints values of S, lt, θl, θr, and es.
S is increased and then compared to Smax.
If S < Smax, the calculations start over with new value for S
If S > Smax, then the program ends.

10. Steering Error Output for Frame 1
Table Frame 1
Steering Error Output for Frame 1
s (in)
lt (in)
Ol (rad)
Or (rad)
es (in)

11. Cost Analysis *Maximum cost if available part are unusable ac425020-12
QTY
Cost Each
Cost
11-inch Rack and Pinion
425145 1 $
Double U-Joint $
Tie rods
425120 2 $ $
Steering Shaft Coupler
425251 $ $
Tie Rod Clevis
425120CV $ $
Splined Shaft
 ac 3 $ $
Steering Wheel
GSW187 $
Steering Knucle Set
MA_319997 $
*Maximum cost if available part are unusable

12. Parts 11” Rack-and-Pinion Double U-Joint Tie Rods
Steering Shaft Coupler
Splined Shaft

13. Deliverables Confirm dimensions of steering design.
Evaluate available resources.
Create a cost analysis of steering parts needed.
Acquire all parts for steering system.
Assemble parts together.
Test assembled parts with original design values.

14. Timeline Timeline Deliverables Early Sept. –Mid Sept.
-Confirm dimensions of design.
-Evaluate avalible resources.
Mid Sept.- Early Oct.
-Create cost analysis for steering parts.
-Gather steering parts.
Early Oct.- Mid Oct.
-Begin assembling.
Mid Oct.- Early Nov.
-Continue assembling parts
-Test and compare assembled parts with orginal design.
Early Nov.- Early Dec.
-Record data.
-Perform final test of steering and fine tune.