My friend I'd recommend 2 books. The first is Milliken - Racecar vehicle dynamics. Or my book The Dynamics of the Race Car. Both will give you an excellent grounding.
No. The reason for this is the pushrod force is dictated to by the spring. When you do the numbers, the results come out the same as when you didn't do it with the pushrod. I hope this helps!
No you don't. The primary reason for this it is reacted by the spring and it takes the vertical load. For an extended analysis I did the numbers on it and it turned out to be exactly the same. Also this visualisation produces spot on roll correlation every time! I hope this helps.
I'm not sure if I understood correctly, but it seems like a method similarly used in The Racing and High-performance Tire by Paul Haney, pages 219-221. Except, in Haney's approach, F_L and F_R have a direction parallel to their respective IC lines and are directly applied at the RC (which you said isn't fully correct). Having the force vectors directed along these lines, the jacking force can be quickly derived. I am quite confused about force application points for suspension geometry tbh. In your video, for example, why would translate tyre forces directly below the c.g. and not at the respective ICs or at the RC?
Hello and welcome to the ChassisSim TH-cam channel. Remember all vehicle motion revolves around forces and moments about the centre of gravity. We need to take a step back here. I want you to go to the 3:47s mark and then take a Free Body Diagram. Run through those numbers and then cross reference it to the asymmetric case. You'll then see the power of the force based approach. However one thing I will say about having F_L and F_R always parrallel to the IC doesn't always apply. However work through the FBD proof and you'll see it comes out in the wash.
Hello, What would you recommend would be a good starting point for someone who wants to understand race car vehicle dynamics? I have been doing some reading already but would like a solid foundation. Are books like tune to win a good start?
Hey Guys. Sorry about those multiple responses. When I made those comments TH-cam seemed to be having a bad hair day and wasn't telling me those responses were being uploaded! Anyway wolfragee this should answer your questions!
I really don't believe this is right. All you are doing is finding the kinematic roll centre after taking account of suspension movements. That does not make it the force based roll centre. I have been using the method you are presenting here for 25 years, it is still only an approximation of the true force based roll centre location. If you read about how designers do calculate the real force based roll centre you have to include data about the steering arms (which transmit part of the cornering force) and tyre performance as a minimum.
Patrick if you actually follow the video closely you'll see the force based roll centre derivation right there. To keep things simple I've just used a simple 2D visulaisation but re watch it again. The late Bill Mitchell (founder of WinGeo) did a paper on this back in 2006, and the work seen here is a continuation of this. I also outline the maths of this in my racecar engineering articles and my book the dynamics of the racecar.
However the ultimate proof of the pudding is in the eating. The following link shows actual vs simulated, www.chassissim.com/blog/chassissim-news/what-makes-chassissim-unique No grip factors and the simulation is fully transient. I should also add that was a non downforce cars. So my question to you is that if this approach is not valid how can this correlation be achieved?
ChassisSim I admit I'm afraid I really wouldn't have a clue how to do that, but I have read what other chassis designers have said about force based roll centre calculation and it is not this, you need to understand how the tyre response varies with load and include that in the force calculation. Maybe they have deliberately tried to make it sound even more complicated by including the steering arm, I don't know, but they seem to believe it is significant enough to alter the result?
Pat - There is actually a really simple way of doing this and proving it to yourself. For an applied force F in any mechanical system there a movement of say del_x. All those sum up to the applied forces plus what ever geometry effects kick in. Then if the suspension arm has a cross sectional area say 4 times that of the steering arm, which is taking the bulk of the force? Also when you get home pop your head under the car and look at the relative bulk of lower control arm to the steering rod. This will answer your questions in spade.
Just saying this to help you improve your videos, but you are using the word basically as a crutch word, you go to it a lot and takes the listener. Just have listen and you'll notice it.
Valuable insight - however. Please prepare your speech, and practice it before you record it. The repeated words, basically, etc. very very distracting from the content. You've got a lot to offer, just concentrate on the delivery and oral presentation. Good job mate keep it up. Please re-do the narrative and repost - love to see your progress. ! Cheers Garret.
No. The reason for this is the pushrod force is dictated to by the spring. When you do the numbers, the results come out the same as when you didn't do it with the pushrod. I hope this helps!
No you don't. The primary reason for this it is reacted by the spring and it takes the vertical load. For an extended analysis I did the numbers on it and it turned out to be exactly the same. Also this visualisation produces spot on roll correlation every time! I hope this helps.
No you don't. The primary reason for this it is reacted by the spring and it takes the vertical load. For an extended analysis I did the numbers on it and it turned out to be exactly the same. Also this visualisation produces spot on roll correlation every time! I hope this helps.
No you don't. The primary reason for this it is reacted by the spring and it takes the vertical load. For an extended analysis I did the numbers on it and it turned out to be exactly the same. Also this visualisation produces spot on roll correlation every time! I hope this helps.
No you don't. The primary reason for this it is reacted by the spring and it takes the vertical load. For an extended analysis I did the numbers on it and it turned out to be exactly the same. Also this visualisation produces spot on roll correlation every time! I hope this helps.
No you don't. The primary reason for this it is reacted by the spring and it takes the vertical load. For an extended analysis I did the numbers on it and it turned out to be exactly the same. Also this visualisation produces spot on roll correlation every time! I hope this helps.
![[UNCUT] "บอสณวัฒน์" แฉ! แหล่งซุกเงินแก๊งบอส ขยันผิดที่ไม่กี่ปีก็เข้าคุก l คนดังนั่งเคลียร์ l17ต.ค.67](http://i.ytimg.com/vi/BL56qIfXYZM/mqdefault.jpg)
My friend I'd recommend 2 books. The first is Milliken - Racecar vehicle dynamics. Or my book The Dynamics of the Race Car. Both will give you an excellent grounding.
No. The reason for this is the pushrod force is dictated to by the spring. When you do the numbers, the results come out the same as when you didn't do it with the pushrod. I hope this helps!
No you don't. The primary reason for this it is reacted by the spring and it takes the vertical load. For an extended analysis I did the numbers on it and it turned out to be exactly the same. Also this visualisation produces spot on roll correlation every time! I hope this helps.
I'm not sure if I understood correctly, but it seems like a method similarly used in The Racing and High-performance Tire by Paul Haney, pages 219-221. Except, in Haney's approach, F_L and F_R have a direction parallel to their respective IC lines and are directly applied at the RC (which you said isn't fully correct). Having the force vectors directed along these lines, the jacking force can be quickly derived.
I am quite confused about force application points for suspension geometry tbh. In your video, for example, why would translate tyre forces directly below the c.g. and not at the respective ICs or at the RC?
Hello and welcome to the ChassisSim TH-cam channel. Remember all vehicle motion revolves around forces and moments about the centre of gravity. We need to take a step back here. I want you to go to the 3:47s mark and then take a Free Body Diagram. Run through those numbers and then cross reference it to the asymmetric case. You'll then see the power of the force based approach.
However one thing I will say about having F_L and F_R always parrallel to the IC doesn't always apply. However work through the FBD proof and you'll see it comes out in the wash.
do we need to include the forces from the push rod in the calculation of forced based roll center?
Hello, What would you recommend would be a good starting point for someone who wants to understand race car vehicle dynamics? I have been doing some reading already but would like a solid foundation. Are books like tune to win a good start?
Hey Guys. Sorry about those multiple responses. When I made those comments TH-cam seemed to be having a bad hair day and wasn't telling me those responses were being uploaded! Anyway wolfragee this should answer your questions!
Sir r these undergraduate level??
No you don't. The reason for this is the pushrod is effectively an extension of the spring.
Is the data and dynamics race engineering website still available?
Yes it is. www.dataanddynamics.com.au/
Yes it is still up - Here is the link - www.dataanddynamics.com.au
basically
I really don't believe this is right. All you are doing is finding the kinematic roll centre after taking account of suspension movements. That does not make it the force based roll centre. I have been using the method you are presenting here for 25 years, it is still only an approximation of the true force based roll centre location. If you read about how designers do calculate the real force based roll centre you have to include data about the steering arms (which transmit part of the cornering force) and tyre performance as a minimum.
Patrick if you actually follow the video closely you'll see the force based roll centre derivation right there. To keep things simple I've just used a simple 2D visulaisation but re watch it again. The late Bill Mitchell (founder of WinGeo) did a paper on this back in 2006, and the work seen here is a continuation of this. I also outline the maths of this in my racecar engineering articles and my book the dynamics of the racecar.
In terms of your comment on steering arms do the compatibility numbers and you'll see where the bulk of the forces are transmitted.
However the ultimate proof of the pudding is in the eating. The following link shows actual vs simulated, www.chassissim.com/blog/chassissim-news/what-makes-chassissim-unique
No grip factors and the simulation is fully transient. I should also add that was a non downforce cars. So my question to you is that if this approach is not valid how can this correlation be achieved?
ChassisSim I admit I'm afraid I really wouldn't have a clue how to do that, but I have read what other chassis designers have said about force based roll centre calculation and it is not this, you need to understand how the tyre response varies with load and include that in the force calculation. Maybe they have deliberately tried to make it sound even more complicated by including the steering arm, I don't know, but they seem to believe it is significant enough to alter the result?
Pat - There is actually a really simple way of doing this and proving it to yourself. For an applied force F in any mechanical system there a movement of say del_x. All those sum up to the applied forces plus what ever geometry effects kick in. Then if the suspension arm has a cross sectional area say 4 times that of the steering arm, which is taking the bulk of the force? Also when you get home pop your head under the car and look at the relative bulk of lower control arm to the steering rod. This will answer your questions in spade.
Just saying this to help you improve your videos, but you are using the word basically as a crutch word, you go to it a lot and takes the listener. Just have listen and you'll notice it.
Valuable insight - however. Please prepare your speech, and practice it before you record it. The repeated words, basically, etc. very very distracting from the content. You've got a lot to offer, just concentrate on the delivery and oral presentation. Good job mate keep it up. Please re-do the narrative and repost - love to see your progress. ! Cheers Garret.
No. The reason for this is the pushrod force is dictated to by the spring. When you do the numbers, the results come out the same as when you didn't do it with the pushrod. I hope this helps!
No you don't. The primary reason for this it is reacted by the spring and it takes the vertical load. For an extended analysis I did the numbers on it and it turned out to be exactly the same. Also this visualisation produces spot on roll correlation every time! I hope this helps.
No you don't. The primary reason for this it is reacted by the spring and it takes the vertical load. For an extended analysis I did the numbers on it and it turned out to be exactly the same. Also this visualisation produces spot on roll correlation every time! I hope this helps.
No you don't. The primary reason for this it is reacted by the spring and it takes the vertical load. For an extended analysis I did the numbers on it and it turned out to be exactly the same. Also this visualisation produces spot on roll correlation every time! I hope this helps.
No you don't. The primary reason for this it is reacted by the spring and it takes the vertical load. For an extended analysis I did the numbers on it and it turned out to be exactly the same. Also this visualisation produces spot on roll correlation every time! I hope this helps.
No you don't. The primary reason for this it is reacted by the spring and it takes the vertical load. For an extended analysis I did the numbers on it and it turned out to be exactly the same. Also this visualisation produces spot on roll correlation every time! I hope this helps.