• This forum is the machine-generated translation of www.cad3d.it/forum1 - the Italian design community. Several terms are not translated correctly.

design and optimization of a car circle

  • Thread starter Thread starter a.forte2
  • Start date Start date

a.forte2

Guest
Hello everyone, I introduce myself: My name is alex and I'm a mechanical engineering student. I have to do an optimization job, more than anything, on a rim of a car; I have already available the cad 3d on inventor, and this is where I will work. the things that are not clear to me are: which are actually the loads agents on the circle, and how to determine them quantitatively, because as only given I have practically only the mass of the car... I know that surely the circle must be able to withstand the weight of the car (amplified I believe from the suspensions), to endure loads due to the impact with various objects, and to resist the impact when for example a difference in altitude, that can be a hole or a small garden... But for example, I don't know if I have to consider the pair of brakes in case of braking, or other types of forces... once you understand the loads agents I think that then just put them on inventor and do static, dynamic and fatigue checks always on the software itself... thanks to who will help me a
 
You are a student ... the best weapon of any mechanical engineering student is the free body diagram.

in first approximation: parts from a vehicle (just one with two wheels so much the concept is that, it changes only the divide the forces by 2 or by 4), draw it in slope and write all the static and inertial forces that act.
then write the reactions to the contact point of the wheel with the ground and here is your loads on the circle.

then clearly the geometry of the suspensions will insert flexional components in the direction out of your sheet (camber, convergence etc.). so the problem becomes 3d ...but to solve it you have to know the suspension.. and then you no longer design a circle but you are a chassis area designer of a car house :d

already a two-dimensional setting with horizontal, vertical and torque loads in the rotation plane of the wheel, I think they give a good degree of approximation to be something academic.

if you struggle to set the free body diagram alone (grave) or simply want to do the cool and consider everything, know that the balance of force agents to the wheel is one of the great cornerstones of the vehicle mechanics. schematization finds it on any dedicated textbook.
 
Stan9411 said:
You are a student ... the best weapon of any mechanical engineering student is the free body diagram.

in first approximation: parts from a vehicle (just one with two wheels so much the concept is that, it changes only the divide the forces by 2 or by 4), draw it in slope and write all the static and inertial forces that act.
then write the reactions to the contact point of the wheel with the ground and here is your loads on the circle.

then clearly the geometry of the suspensions will insert flexional components in the direction out of your sheet (camber, convergence etc.). so the problem becomes 3d ...but to solve it you have to know the suspension.. and then you no longer design a circle but you are a chassis area designer of a car house :d

already a two-dimensional setting with horizontal, vertical and torque loads in the rotation plane of the wheel, I think they give a good degree of approximation to be something academic.

if you struggle to set the free body diagram alone (grave) or simply want to do the cool and consider everything, know that the balance of force agents to the wheel is one of the great cornerstones of the vehicle mechanics. schematization finds it on any dedicated textbook.
Click to expand...
Hello, first of all thank you very much for the answer... Unfortunately yes ahahahahah, I should also consider suspensions and treat the problem in a three-dimensional way, and that's exactly what makes me trouble... for a two-dimensional analysis I had followed exactly that pattern, a car placed on a sloped plane, and I had calculated static loads agents on the circle, but then I do not know how these change according to the geometry of the suspension, which in my case should be quadrilateral (or for simplicity I was told to be able to consider also a suspension to obliqui arms); Moreover I should also consider the dynamic loads that could act on the circle, such as the load that is created when you overcome a obstacle like a step, or the braking couple during braking precisely
 
Stan9411 said:
It's google scholar so nothing illegal I think. If not please admins to remove the post
Sixth link refers to pdf of a book that treats vehicle dynamics in the presence of obstacles. from page 30 onwards you should find some things that interest you.

definitely is a complex problem. take some time and throw out similar links. It's not something you can formalize on your own.
Click to expand...
All right, thank you so much for being interested and helping me... I just downloaded that book and these days I will try to study that part in depth and try to find a solution. . Thank you again!
 
a.forte2 said:
Hello everyone, I introduce myself: My name is alex and I'm a mechanical engineering student. I have to do an optimization job, more than anything, on a rim of a car; I have already available the cad 3d on inventor, and this is where I will work. the things that are not clear to me are: which are actually the loads agents on the circle, and how to determine them quantitatively, because as only given I have practically only the mass of the car... I know that surely the circle must be able to withstand the weight of the car (amplified I believe from the suspensions), to endure loads due to the impact with various objects, and to resist the impact when for example a difference in altitude, that can be a hole or a small garden... But for example, I don't know if I have to consider the pair of brakes in case of braking, or other types of forces... once you understand the loads agents I think that then just put them on inventor and do static, dynamic and fatigue checks always on the software itself... thanks to who will help me a
Click to expand...
stick to the evidence that must pass for its validation
search for the validation tests of the wheels, these considate all the load conditions to which your wheel is subjected and therefore dimension it so that these tests exceed
all other considerations will also be interesting, but what matters is that your wheel exceeds the validation tests provided by the rules
Hi.
 
Pierandrea58 said:
stick to the evidence that must pass for its validation
search for the validation tests of the wheels, these considate all the load conditions to which your wheel is subjected and therefore dimension it so that these tests exceed
all other considerations will also be interesting, but what matters is that your wheel exceeds the validation tests provided by the rules
Hi.
Click to expand...
hello, thank you very much for your intervention; I tried to search on the web the conditions in which the tests are carried out to obtain such certification, but honestly I did not manage to find documents or test reports already made that express everything clearly; as regards the analysis of the loads I think I have partially solved, I was told to consider as more dangerous load that deriving from the overcoming of an obstacle, and to dimensional in the first line the circle according to this, considering the other loads agents on the wheel, such as forces during the journey of a curve, as loads that go to stress fatigue the circle
 

Forum statistics

Threads
44,997
Messages
339,767
Members
4
Latest member
ibt

Members online

No members online now.
Total: 1 (members: 0, guests: 1)
Back
Top