Car test, and vibrations problem

Click For Summary
SUMMARY

The discussion centers on evaluating the performance of shock absorbers in three cars with identical mass and springs but different shock absorber configurations. The analysis concludes that the third car, exhibiting critical damping, provides the best ride quality by quickly returning to its original state after encountering a bump. The first car, with worn-out shocks, demonstrates excessive vibrations, while the second car offers a compromise between comfort and stability. The key takeaway is that changes in acceleration, or jerk, significantly impact passenger comfort.

PREREQUISITES
  • Understanding of vehicle dynamics and suspension systems
  • Familiarity with concepts of damping and vibration analysis
  • Knowledge of acceleration and its effects on ride comfort
  • Basic physics principles related to motion and forces
NEXT STEPS
  • Research "Critical Damping in Suspension Systems" to understand optimal shock absorber performance
  • Explore "Vibration Analysis Techniques" for assessing vehicle comfort
  • Study "Vehicle Dynamics and Handling" to learn about the impact of suspension on driving experience
  • Investigate "Shock Absorber Testing Methods" to evaluate performance metrics
USEFUL FOR

Automotive engineers, suspension system designers, and anyone involved in vehicle performance optimization will benefit from this discussion.

Mohamed BOUCHAKOUR
Messages
15
Reaction score
0

Homework Statement


in tests to choose the most comfortable shock absorbents, 3 cars are used, with the same mass "m", and the same springs, but different shock absorbents. the graphs show the changes in car height when passing over a bump (y=0 being the normal state of the car).
9.png

.
.
.
-Witch car has the best shock absorbent?
(P.S: I'm not sure if I've got the correct translation for "shock absorbents", but i hope you'll get what i mean)

Homework Equations



The Attempt at a Solution


As far as i know, it's the changes in motion that cause discomfort not the movement itself, so, for the 3rd car, it returns almost immediately to it's original state, and for the 1st it vibrates violently, so both would be quite bad.
as for the 2nd, it's a compromise between the two, it ensures a smooth transition to the normal state.

i don't know if it's the correct answer, or I completely missed the point.
 

Attachments

  • 9.png
    9.png
    7.1 KB · Views: 430
Physics news on Phys.org
Changes in acceleration (jerk) are felt as unpleasant, constant acceleration is a smaller issue.
2 or 3 - hard to tell, I guess 2 is better. 3 will be very bad initially, while 2 has some bouncing later.
 
Case 1 corresponds to shocks which are worn out and if driven over a road with a periodic contour could result in a loss of control. I experienced this on the old bridge across Biloxi Bay which was later destroyed by Katrina. Case 2 represents shocks with a bit of wear. Case 3 is a case of critical damping or new shocks which give the best ride.
 
  • Like
Likes   Reactions: scottdave

Similar threads

  • · Replies 37 ·
2
Replies
37
Views
4K
Replies
13
Views
2K
Replies
2
Views
2K
  • · Replies 3 ·
Replies
3
Views
5K
  • · Replies 1 ·
Replies
1
Views
3K
Replies
4
Views
3K
Replies
5
Views
10K
Replies
1
Views
3K
  • · Replies 5 ·
Replies
5
Views
2K
  • · Replies 1 ·
Replies
1
Views
4K