Calculating/Simulating Vehicle Braking Force

[Gazzoo]

Hi All,

I know this type of question has been asked many times but I need help to clarify for myself if I'm doing the right thing. So here goes...

I am trying to simulate/understand the forces on a vehicle as it is traveling on a road. In particular as it is traveling up hills. So if I have my equations correct the primary negative or braking force would be gravity and would be tangential to the inclined plane. This would be calculated using

F = mg sin(ang)

So for an inclined plane/road at 10 deg, and a 3000kg vehicle the tangential gravitational force would be

F = 3000 x 9.81 x sin(10) = 5110.47 N

So is it correct to assume that this force is applied at the wheel contact surface which may have a radius of say 0.2m producing a torque of

T = F x R = 5110.47 * 0.20 = 1022.09 Nm

So in order to mimic this same force/torque using the car brakes they would need to generate a total negative braking torque of the same amount right?

Do I need to bother with speed/momentum in any manner when trying to calculate this braking force as well as the vehicle is traveling up the incline?

Thanks for your help!

 

[esalihm]

first part is correct, it is mg*sin(ang)

you are talking about a car, a car has tires and tires cause friction
if the car is moving without sliding (I assume this is the case here) you need to consider static friction too, it is static because the contact point of the tire does not move relative to the inclined plane.

the breaks produce a torque that compensates for both of those
and let life stay as simple as it is do not consider any momentum in any of these cases

 

[m2003]

I would say that your calculations and understanding of the forces on a vehicle are correct. The primary negative or braking force on a vehicle traveling up an inclined plane would indeed be gravity, which can be calculated using the equation F = mg sin(ang). This force would be applied at the wheel contact surface and would produce a torque, which can also be calculated using T = F x R, where R is the radius of the wheel. In order to mimic this same force using the car brakes, they would need to generate a negative braking torque of the same amount.

However, it is important to consider other factors such as speed and momentum when calculating the braking force on a vehicle. The vehicle's speed and momentum will affect how quickly it can come to a stop and the amount of force required from the brakes. Additionally, other forces such as air resistance and friction from the road surface should also be taken into account.

In order to accurately simulate the forces on a vehicle traveling on an inclined plane, it may be necessary to use more complex equations and models that take into account these other factors. It is always important to consider all variables and factors when conducting scientific simulations or calculations.