Caster Angles in Shopping Carts: How to Control Wheel Paths

Click For Summary
SUMMARY

The discussion focuses on the mechanics of caster angles in shopping carts and their effect on wheel alignment. A positive caster angle allows wheels to return to a straight path due to the vertical pivot axis being positioned behind the wheel axis, while a negative caster angle leads to instability. The principles discussed are applicable to both shopping carts and race cars, emphasizing the importance of caster displacement in steering dynamics. A reference to a Wikipedia article on caster angle provides additional context for understanding these concepts.

PREREQUISITES
  • Understanding of caster angle mechanics
  • Familiarity with force diagrams
  • Basic knowledge of wheel alignment principles
  • Experience with vehicle dynamics, particularly in race car setups
NEXT STEPS
  • Research "Caster angle effects on vehicle handling" for deeper insights
  • Study "Force diagrams in mechanical systems" to visualize concepts
  • Explore "Shopping cart wheel design" for practical applications
  • Investigate "Race car suspension geometry" to understand advanced caster setups
USEFUL FOR

Automotive engineers, race car drivers, mechanical designers, and anyone interested in the physics of steering dynamics and wheel alignment.

Charles123
Messages
131
Reaction score
0
Can you draw a force diagram to explain how a positive caster angle makes wheels return to a straight line in a shopping kart (as an example), while a negative caster angle would have the opposite effect.
Thx
 
Physics news on Phys.org
Charles123 said:
Can you draw a force diagram to explain how a positive caster angle makes wheels return to a straight line in a shopping kart (as an example), while a negative caster angle would have the opposite effect.
Thx

For this question you don't want the PF crowd, you want the people who set up and drive race cars.
 
A shopping cart wheel uses a caster displacement, the pivot axis is vertical, and the wheel axis is behind the pivot axis, so that if the wheel if off to the side, it gets pushed back to straighten it up when the cart is pushed forwards.

A car uses an angled pivot to get a similar caster effect. Wiki article:

http://en.wikipedia.org/wiki/Caster_angle
 
I understand the idea, but I would like to see a force diagram of it. Thx
 

Similar threads

Undergrad Realistic steering wheel angle when car follows points along a path
  • · Replies 21 ·
Replies
21
Views
3K
Undergrad Solving Wheel Coming to a Stop: FBD, Friction & Hysteresis
  • · Replies 22 ·
Replies
22
Views
5K
Undergrad How Does Changing Mass and Spring Force Affect Watch Oscillators?
  • · Replies 11 ·
Replies
11
Views
2K
Graduate How does a 1-wheeled motorcycle turn?
  • · Replies 16 ·
Replies
16
Views
3K
Undergrad Question about an example in Newton's Principia
  • · Replies 1 ·
Replies
1
Views
1K
Undergrad A perfectly stiff wheel cannot roll on a stiff floor?
  • · Replies 116 ·
4
Replies
116
Views
13K
Undergrad Finding the max angle of a longboard deck before the wheels slip
  • · Replies 8 ·
Replies
8
Views
2K
Graduate Modeling the damping of a physical rigid pendulum
  • · Replies 1 ·
Replies
1
Views
2K
Graduate Can Weight Transfer Cause a Car to Stay in a Stuck Position?
  • · Replies 14 ·
Replies
14
Views
3K
Undergrad The wheel on old Horse-Cart problem
  • · Replies 13 ·
Replies
13
Views
12K