Successfully reported this slideshow.
We use your LinkedIn profile and activity data to personalize ads and to show you more relevant ads. You can change your ad preferences anytime.
Analysis of Passive Quarter Model Suspension
System;
enhanced adaptation to Semi-Active control
By: Matthew Fenech
Tutor: ...
Vehicle Suspensions
Aims of a Suspension System
•Vehicle Isolation from road disturbances
•Link between the road and the v...
Types of Suspension Systems
•Passive
•Active
•Semi-Active
• EH
• ER
• MRF
Scopes and Objectives ofWork
• Research of passive & semi-active Suspension Systems
• Mathematical modelling
• Data acquis...
Mathematical Modelling
Sprung Mass
Unsprung
Mass
Road
Mathematical Modelling (Free body Diagram)
𝐹𝑠 = 𝑀 𝑦 (Upward Direction)
y =
1
M1
[−ksy + ksx − csy + csx]
Sprung Mass
Mathematical Modelling (Free body Diagram)
𝐹𝑠 = 𝑀 𝑦 (Upward Direction)
x =
1
M2
[k 𝑠 y − x + C 𝑠 y − x − k 𝑢𝑠 x − r − C 𝑢𝑠...
SIMULINK® Passive Model
ParametricValues
ModelValues
M1 Sprung Mass 287kg
M2 Unsprung Mass 35kg
Ks Sprung Mass Stiffness 25500N/m
Kus Tyre Stiffne...
Semi-Active adaptation
• Skyhook control
• ON-OFF algorithm 1. Fa = cSad(y − x)
2. cSad =
cmax, if ca > cmax
ca, if cmin <...
Semi-Active damping control
SIMULINK® Responses: Displacement, Step
Passive 0.07115 m
Semi-Active 0.05778 m
SIMULINK® Responses: Displacement, Bump
Passive 0.01727 m
Semi-Active 0.01865 m
SIMULINK® Responses: Acceleration, Step
Passive 14.64 m/s2
Semi-Active 9.417 m/s2.
SIMULINK® Responses: Acceleration, Bump
Passive 13.13m/s2
Semi-Active 7.165m/s2
SIMULINK® Responses:Wheel Deflection, Step
Passive 0.006366m
Semi-Active 0.018m
SIMULINK® Responses:Wheel Deflection, Bump
Passive 0.0495 m
Semi-Active 0.02501 m
Rig Design
Passive SuspensionTest Rig
Recommendations
• Rig improvement
• Cam Actuator, Motor Driven
• LVDT
• Acceleration Measurement
• Structure Improvement
•...
Conclusion
Step Input
Displacement (m) Acceleration (𝐦/𝐬 𝟐
) Wheel Deflection (m)
Passive 0.07115 14.64 0.006366
Semi-Acti...
Thank you for your attention!
Questions?
Comfort Specs iso2631
Magnitude of OverallVibrationTotalValue Discomfort Response
< 0.315ms−2 Not uncomfortable
0.315 ms−2...
Costs
€118.51
€497.32
€59.46
€6.00
Costs
Raw Material Components Literature Services
Model Mass Acquisition
Model & Specs WEIGHT
Toyota Aygo, 1.0ltr, 5 Speed, 3 Door 1240kg
Ford Fiesta, 4-Dr, sedan 1169kg
Vw...
Spring Selection (Sprung Mass)
Spring-Sprung
Mass
(Kg)
Natural
Freq.=1.5Hz
Stiffness
(N/m)
Stiffness
(N/mm)
Static Deflect...
Spring Selection (Unsprung Mass)
Spring Unsprung
Mass
(Kg)
Natural
Freq.=16Hz
K (N/m) K
(N/mm)
Static Deflection
(m)
Body
...
Rig 5Kg response
SIMULINK® Responses: RMS, Bump
Rig 0.5 Kg Response
Rig 0.5 Kg Response
-20
-10
0
10
20
30
40
50
60
70
80
0 0.5 1 1.5 2 2.5 3 3.5 4 4.5 5
Displacement(m)
Time (sec)
Test 1 Te...
SIMULINK® Responses: RMS, Step
Upcoming SlideShare
Loading in …5
×

Analysis of passive quarter model suspension system; enhanced adaptation to semi-active control.

1,627 views

Published on

Analysis of passive quarter model suspension system

Published in: Automotive
  • Be the first to comment

Analysis of passive quarter model suspension system; enhanced adaptation to semi-active control.

  1. 1. Analysis of Passive Quarter Model Suspension System; enhanced adaptation to Semi-Active control By: Matthew Fenech Tutor: Ing.Claire Seguna
  2. 2. Vehicle Suspensions Aims of a Suspension System •Vehicle Isolation from road disturbances •Link between the road and the vehicle •Supporting the vehicle’s static weight
  3. 3. Types of Suspension Systems •Passive •Active •Semi-Active • EH • ER • MRF
  4. 4. Scopes and Objectives ofWork • Research of passive & semi-active Suspension Systems • Mathematical modelling • Data acquisition (real) to be put in the model (20mph)(tyre) • Math models generation on SIMULINK® • Hardware Design Stages • Semi-Active Control Study • Semi-Active Model • Data analysis of both systems and the rig response
  5. 5. Mathematical Modelling Sprung Mass Unsprung Mass Road
  6. 6. Mathematical Modelling (Free body Diagram) 𝐹𝑠 = 𝑀 𝑦 (Upward Direction) y = 1 M1 [−ksy + ksx − csy + csx] Sprung Mass
  7. 7. Mathematical Modelling (Free body Diagram) 𝐹𝑠 = 𝑀 𝑦 (Upward Direction) x = 1 M2 [k 𝑠 y − x + C 𝑠 y − x − k 𝑢𝑠 x − r − C 𝑢𝑠 𝑥 − r ] Unsprung Mass
  8. 8. SIMULINK® Passive Model
  9. 9. ParametricValues ModelValues M1 Sprung Mass 287kg M2 Unsprung Mass 35kg Ks Sprung Mass Stiffness 25500N/m Kus Tyre Stiffness 145000N/m Cs Sprung Damping 2500Ns/m Cus Tyre Damping 0 fn sprung Sprung Natural Frequency 1.5Hz fn unsprung Unsprung Natural Frequency 16Hz
  10. 10. Semi-Active adaptation • Skyhook control • ON-OFF algorithm 1. Fa = cSad(y − x) 2. cSad = cmax, if ca > cmax ca, if cmin < ca < cmax cmin, if ca < cmin 3. ca = cskyy y−x , only valid when y y − x > 0 , otherwise ca=cmin
  11. 11. Semi-Active damping control
  12. 12. SIMULINK® Responses: Displacement, Step Passive 0.07115 m Semi-Active 0.05778 m
  13. 13. SIMULINK® Responses: Displacement, Bump Passive 0.01727 m Semi-Active 0.01865 m
  14. 14. SIMULINK® Responses: Acceleration, Step Passive 14.64 m/s2 Semi-Active 9.417 m/s2.
  15. 15. SIMULINK® Responses: Acceleration, Bump Passive 13.13m/s2 Semi-Active 7.165m/s2
  16. 16. SIMULINK® Responses:Wheel Deflection, Step Passive 0.006366m Semi-Active 0.018m
  17. 17. SIMULINK® Responses:Wheel Deflection, Bump Passive 0.0495 m Semi-Active 0.02501 m
  18. 18. Rig Design
  19. 19. Passive SuspensionTest Rig
  20. 20. Recommendations • Rig improvement • Cam Actuator, Motor Driven • LVDT • Acceleration Measurement • Structure Improvement • Further Frequency analysis
  21. 21. Conclusion Step Input Displacement (m) Acceleration (𝐦/𝐬 𝟐 ) Wheel Deflection (m) Passive 0.07115 14.64 0.006366 Semi-Active 0.05778 9.417 0.018 % Improvement 18.79% 35.6% -64.3% Bump Input Displacement (m) Acceleration (𝐦/𝐬 𝟐 ) Wheel Deflection (m) Passive 0.01727 13.13 0.0495 Semi-Active 0.01865 7.165 0.02501 % Improvement -7.3% 45.4% 49.47%
  22. 22. Thank you for your attention!
  23. 23. Questions?
  24. 24. Comfort Specs iso2631 Magnitude of OverallVibrationTotalValue Discomfort Response < 0.315ms−2 Not uncomfortable 0.315 ms−2 < 0.03 ms−2 Slightly uncomfortable 0.8 ms−2 < 1.6 ms−2 Fairly uncomfortable 0.5 ms−2< 1 ms−2 Uncomfortable 1.25 ms−2 < 2.5 ms−2 Very uncomfortable 2.0 ms−2 < Extremely uncomfortable
  25. 25. Costs €118.51 €497.32 €59.46 €6.00 Costs Raw Material Components Literature Services
  26. 26. Model Mass Acquisition Model & Specs WEIGHT Toyota Aygo, 1.0ltr, 5 Speed, 3 Door 1240kg Ford Fiesta, 4-Dr, sedan 1169kg Vw Polo 1030kg Bmw, 1-series, 116i 1350kg Citroen C2, 1.4i 956kg Average 1149kg
  27. 27. Spring Selection (Sprung Mass) Spring-Sprung Mass (Kg) Natural Freq.=1.5Hz Stiffness (N/m) Stiffness (N/mm) Static Deflection (m) 1 9.425 88.83 0.09 0.1104 2 9.425 177.65 0.18 0.1104 3 9.425 266.48 0.27 0.1104 4 9.425 355.31 0.36 0.1104 5 9.425 444.13 0.44 0.1104
  28. 28. Spring Selection (Unsprung Mass) Spring Unsprung Mass (Kg) Natural Freq.=16Hz K (N/m) K (N/mm) Static Deflection (m) Body mass 1.125 100.531 11369.78 11.37 0.0010 1 2.25 100.531 22739.57 22.74 0.0010 2 3.375 100.531 34109.35 34.11 0.0010 3 4.5 100.531 45479.14 45.48 0.0010 4 5.625 100.531 56848.92 56.85 0.0010 5
  29. 29. Rig 5Kg response
  30. 30. SIMULINK® Responses: RMS, Bump
  31. 31. Rig 0.5 Kg Response
  32. 32. Rig 0.5 Kg Response -20 -10 0 10 20 30 40 50 60 70 80 0 0.5 1 1.5 2 2.5 3 3.5 4 4.5 5 Displacement(m) Time (sec) Test 1 Test 2 Test 3
  33. 33. SIMULINK® Responses: RMS, Step

×