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Doubt regarding compliance matrix calculation error in suspension analysis

I have read online help regarding this matter and understand that whenever we perform a standard event (for eg Suspension Analysis-----> Steering, which I am trying on one of the projects), the compliance matrix is calculated for every Joint and then various elements of this matrix are used for calculating different requests such as Ride rate, ride steer and a number of other parameters. The model which I have built has a number of idealized constraints (Convel, spherical, revoulte, fixed joints in the steering template). I have tried to replace as many fixed joints in the suspension templates as possible with bushes to see if it worked, but the problem still persists. There are also no redundant constraints in the model. I have also double checked the communicators that I have used and ensured that none of the parts are inadvertently connected to the ground. without the matrix, none of the requests which use this matrix are being calculated. The model I am trying to simulate is that of a tandem axle front suspension with bell-crank equalizing links and twin steering. I have also taken a look at the same assembly from the shared truck database. There seem to be quite a lot of idealized constraints in that model, but still there seems to be no issue when I simulate a similar steering event using that model. Can anybody suggest any corrections I may be able to incorporate into my model to make it work?
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  • Adding to Alexis comments: There are multiple messages about ride stiffness being too large. I've seen two things in the past that could cause this: 1) Unrealistically high suspension spring rates. If these are too large, the suspension behaves like it's almost locked up, which causes problems with the compliance matrix calculations. 2) If the suspension spring rate is reasonable, but the rotational bushing rates are too high, then the suspension can also behave like it is locked up.
     
    It's less likely that mass is a problem here, but it's still a good practice to put in reasonable values for mass and inertia.
     
    As a test, I would apply vertical inputs (either force or displacement) to the wheels as a function of time, and then plot wheel vertical force vs. wheel vertical deflection, and ensure the basic wheel rate are reasonable (the slope of the force vs. deflection curve).
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  • Adding to Alexis comments: There are multiple messages about ride stiffness being too large. I've seen two things in the past that could cause this: 1) Unrealistically high suspension spring rates. If these are too large, the suspension behaves like it's almost locked up, which causes problems with the compliance matrix calculations. 2) If the suspension spring rate is reasonable, but the rotational bushing rates are too high, then the suspension can also behave like it is locked up.
     
    It's less likely that mass is a problem here, but it's still a good practice to put in reasonable values for mass and inertia.
     
    As a test, I would apply vertical inputs (either force or displacement) to the wheels as a function of time, and then plot wheel vertical force vs. wheel vertical deflection, and ensure the basic wheel rate are reasonable (the slope of the force vs. deflection curve).
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