How to calculate forces on a wheel

In summary: This is based off the assumption that the forces on the wheel are constant, and that the load is distributed evenly across the wheels. Additionally, it is assumed that the wheel is symmetrical about the axle, which is not always the case. With regards to increasing the wheel size, this would presumably result in an increase in the load per wheel, and therefore an increase in the rolling resistance.
  • #1
Maertens
2
0
I have seen a lot of different formulas about the forces acting on a wheel. So now I don't know what to use.

So, I have a vehicule with 4 wheels ( Ø 200 x 50mm) with a load of 900KG. I want to know 3 things:
1. What power I need to start the vehicle to move.
2. What power I need for constant speed 6km/h? The rolling resistance.
3. What force ( pressure) the wheel gives on the floor? When the wheel stand still and when the wheel is rolling? In N/mm².


The wheelcore is made in cast iron and the tread is polyurethane 92 shore A. Tread can be Rubber 68 shore A. The wheel can also be completely made in polyamide 72 shore D.
The floor can be concrete, wood, linoleum.

What are the influences when we double the wheels?
What are the influences when we increase the diameter by 2?

I'm almost sure it's impossible to calculate this. But, I'm satisfied when I have a good 'direction'.
 

Attachments

  • Forces on wheel.pdf
    35.5 KB · Views: 306
Physics news on Phys.org
  • #2
I've never done this type of problem but I think you would need to know what losses were involved when you compressed and released the tyre material. In theory (ideal spring) there are no losses. In the real world tyres are heated by the process an that represent a loss that has to be overcome.
 
  • #3
There are some promising empirical answers on the wikipedia page
http://en.wikipedia.org/wiki/Rolling_resistance#Depends_on_diameter

"For pneumatic tires on hard pavement, it is reported that the effect of diameter on rolling resistance is negligible (within a practical range of diameters).[31][32]"

For doubling the number of wheels, my best guess would be that since the rolling resistance seems to be modeled on a linear coefficient, doubling the wheels (and therefore halving the load per wheel) would have no first order effect.
 

1. How do you calculate the weight of a wheel?

To calculate the weight of a wheel, you need to know its mass and the acceleration due to gravity. The formula for calculating weight is weight = mass x acceleration due to gravity. Therefore, if you know the mass of the wheel, you can multiply it by the acceleration due to gravity (9.8 m/s^2) to find its weight in Newtons (N).

2. How do you calculate the force on a wheel during rotation?

The force on a wheel during rotation can be calculated using the formula F = m x a, where F is the force, m is the mass of the wheel, and a is the acceleration. The acceleration in this case is the centripetal acceleration, which can be calculated using the formula a = v^2 / r, where v is the linear velocity of the wheel and r is the radius of the wheel. Therefore, to calculate the force on a wheel during rotation, you need to know the mass of the wheel, its linear velocity, and its radius.

3. How do you calculate the frictional force on a wheel?

The frictional force on a wheel can be calculated using the formula F = μ x N, where F is the frictional force, μ is the coefficient of friction, and N is the normal force. The normal force is the force exerted by the surface on the wheel, and it is equal to the weight of the wheel. Therefore, to calculate the frictional force on a wheel, you need to know the coefficient of friction and the weight of the wheel.

4. How do you calculate the torque on a wheel?

The torque on a wheel can be calculated using the formula T = F x r, where T is the torque, F is the force acting on the wheel, and r is the radius of the wheel. The force in this case can be any force acting on the wheel, such as the weight, frictional force, or applied force. Therefore, to calculate the torque on a wheel, you need to know the force acting on the wheel and its radius.

5. How do you calculate the net force on a wheel?

The net force on a wheel can be calculated by adding all the forces acting on the wheel in the same direction. For example, if there is an applied force, frictional force, and weight acting on the wheel, you would add them all together to find the net force. The net force is important because it determines the acceleration of the wheel according to Newton's second law, F = ma. Therefore, to calculate the net force on a wheel, you need to know all the forces acting on the wheel and their respective directions.

Similar threads

Replies
11
Views
5K
  • Classical Physics
3
Replies
95
Views
4K
  • Classical Physics
4
Replies
116
Views
10K
  • Introductory Physics Homework Help
Replies
4
Views
524
Replies
23
Views
2K
Replies
22
Views
1K
  • Mechanics
Replies
24
Views
2K
  • Mechanical Engineering
Replies
18
Views
4K
  • Mechanics
Replies
16
Views
2K
Replies
8
Views
2K
Back
Top