How can Simdriveline's 'Vehicle Body' component distinguish between front and rear wheels?

I am using a Vehicle Body (Simdriveline) to represent a car with double tires in Simscape. At the moment, I connected the H-ports of the 8 wheels to the H-port of the Vehicle Body, to represent the fact that they al have the same linear speed. How can the Vehicle Body know which wheels are front wheels and which ones are rear wheels? It needs to know this to calculate the force distribution that is given as an output.

Answer 1

[Sebastian Castro]

You need to use the NR and NF ports in the Vehicle Body block and connect them to the N ports of the tire blocks you want to be rear/front wheels, respectively.

These ports compute the normal force at the rear and front wheels, which is determined by the acceleration of the vehicle body and the dimensions (distance from C.G. to each axle).

Also, note the Number of wheels per axle variable in the Vehicle Body block. This makes sure that the normal force is scaled accordingly depending on how many wheels you have. For example, if there are 4 wheels in an axle the force value is divided by 4 so each wheel gets 1/4 of the force.

From the documentation: If the [above] input is a two-element array, the first number is the front-axle wheel count and the second number the rear-axle wheel count. For example, if the input is the array [2,1], then the front axle is assumed to have two wheels and the rear axle one wheel.

- Sebastian