Generation of Combined Slip Brush Tire Model with Practical Data of 4 Wheel FWD Passenger Vehicle Tire
Problem set 2a- combines slip
This challenge tests your understanding of combined slip brush tire model
This exercise should be done in octave. Turn in your code
• Write an Octave script to show the effect of slip angles (2 through 10 deg in increments of 2) on the Fx vs Fy relationship.
• Use a slip ratio range of 0 to 1 (or 0 to 100%)
Use the combined slip brush tire model we developed in class. Develop your script based on the algorithm we looked at in class. These are your deliverables:
1. Plot showing the effect of different slip angles on Fx vs Fy relationship
2. Error free Octave code
3. Inference from the plot
Problem Set 2b – combined slip – abs and side force
This challenge tests your understanding of combined slip brush tire model
This exercise should be done in octave. Turn in your code
• Write an Octave script to calculate the effective cornering stiffness under different slip ratios (0, 0.15 and 1.0) and fixed slip angle
Use the combined slip brush tire model we developed in class. Develop your script based on the algorithm we looked at in class.
These are your deliverables:
1. Effective cornering stiffness values
2. Error free Octave code
3. Inference from the plot (hint: it is related to ABS and side force)
Problem Set 2c – pacjecka Mz
This challenge tests your understanding of curve fitting using the Pacjecka magic formula
This exercise should be done in octave. Turn in your code
The file “tire_test_data” contains slip angle and aligning torque data.
The file can be downloaded from here: https://drive.google.com/file/d/0B2S2ZJKcURAmd0Vrdm1pSDhUY1k/view?usp=sharing
Using the magic tire formulation, obtain fit coefficients so that your curve describes the tire test data accurately. Write a post-processing routine to
calculate the RMS error of the curve fit. Tune your coefficients so that the RMS error is less than 2.0 Nm. These are your deliverables:
1. Coefficients that meet the RMS criteria (10 points)
2. Plot showing the curve fit (10 points)
3. RMS calculation (10 points)
4. Error free Octave code
Answer set 2a-
Combined Slip:
Octave code-
https://drive.google.com/open?id=1d3Kwo1IIIZvTVutCBeM-hFUF24rt7LuL
Answer set 2b-
combined slip – abs and side force
Slip Ratio (SR) = 0
Cornering Stiffness= Y2-Y1/X2-X1 = 1429.25-0/3 =476.41N/deg =27296.66N/radian
SR=0.10
Cornering Stiffness= Y2-Y1/X2-X1 = 757.54-0/3 = 252.51N/deg =14467.94N/radian
SR=1.0
Cornering Stiffness= Y2-Y1/X2-X1 = 95.23/3 = 31.74 N/deg = 1818N/radian
Octave code-
https://drive.google.com/open?id=1-i0c3B_fxSW4hXEmkeg1vWzPRql415tj
Answer set 2c-
pacjecka Mz (Aligning Torque due to Pneumatic Trail)
Octave code-
https://drive.google.com/open?id=1XJgIVNH5MkRNGqD44-nJ4neWYEmsYmoW