How to make the vehicle mass variable?

I was an occasional user of SimDriveline (Generation 1) and now I try to build a new model from the beginning (on the new version (Generation 2) by understanding all the components and relations in between.

My question is about modeling a working machine (handling equipment) and here the container weight is also included in our driving cycles. So, the vehicle mass is not constant as in the "vehicle body" block. I might add a "mass" to the translational mechanical port of the vehicle body (H) but I couldn't figure out to make it conditional (as the var_load=1, then add the load mass). One way can be engaging the mass by using a friction clutch, but then it should be interpreted as inertia.

I tried to explain in a specific case, but the case can be extended to different applications. Are there any other ideas regarding my question. Thanks in advance.

Evrim

Answer 1

[Steve Miller]

The mass of the vehicle can be made adjustable - see the documentation

https://www.mathworks.com/help/physmod/sdl/ref/vehiclebody.html

The block has an option to include an externally-defined mass and an externally-defined inertia. The mass, inertia, and center of gravity of the vehicle body can vary over the course of simulation in response to system changes.

[Stefano Conti]

How I can define the input of the new CG? The guide say that the input must be a 2-element vector but I don't understand how i can model a 2-element vector in Simulink. I also don't understand with what criterion to define the two values of the position vector to be given as input to the CG port.

[Etelka]

You can define it in workspace then use it in simulink with a constant block.