I would like to ask how would you calculate the wheel rates in pushrod suspension ? What angle should be used for the damper ?

Many thanks

HI Gary,

The installation ratio is a calculated ratio of the installation of your suspension. It is specific to your car. Please see our article covering installation ratio and how to calculate it.

Many Thanks

Hi Sayyed, thanks for the comment. That sounds very interesting. Unfortunately this is not something we would be able to help with but is something that your university can hopefully provide the resources for.

Thanks

Hi John, thanks for the comment. With a fixed rear beam axle the roll centre is located in the centre of the axle. From there the equations should work the same for you.

Thanks

Hi Tim, thanks for the comment. Obtaining roll angle is a task that requires quite a lot of measurement equipment. However, this is the best route for accurately calculating roll moment. The other route would be to draw out your roll centres with a scale drawing or on CAD and then use G data from a data logger to apply to the COG and therefore calculate roll moment using this data.

Thanks

My understanding of changing the roll centre height means that we are changing the moment arm for weight to be transferred under lateral acceleration, so if we increase the roll centre height that effectively means there is a greater moment arm for the weight to be transferred through which would result in a lower roll stiffness

I read the other article that was posted about roll centre and roll moment, but this would suggest the only way to calculate it would be to know the chassis roll angle at a particular lateral acceleration, then calculate the chassis stiffness by calculating the torque (with the variable being the change in distance between to CoG and the roll centre), but obtaining the roll angle seems like quite a difficult task

Thank you!

I’m PhD student in mechanical engineering in dynamic, vibration and control field.

I found a mathematical method based on virtual work principles for the wheel-rate and wheel-shock exact analytical calculations.

I want to experimentally verify my method but I don’t have any equipment such as sensors, actuators and etc.

Can your institute help me to do this verification?
There is a big gap in this subject, so we will be able to publish a valuable paper.

Hi, thanks for the comment. The manual route would be best for you to measure the wheel displacement and spring displacement at the same time whilst working the wheel through full travel. You can then calculate wheel rate with the known spring rate and the installation ratio.

Thanks

Hi Martin, thanks for the comment. Please see our article on anti-roll bars which takes you through your question.

https://suspensionsecrets.co.uk/anti-roll-bars-2/

Best Regards !