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Dependent components added to a double a-arm setup. Have I defined them correctly and will the TESTRIG play nice with them?

I am trying to analyse a kinematically cross-linked double a-arm suspension. I have crated a template and made the standard parts following the conventions used in the fsae_2018 template. The 'gel_lower_control_arm' and 'gel_upright' are conventional.
 
The 'gel_upper_control_arm' is now a big bell-crank that is attached to an additional part 'gel_crosslink_BC' which, in turn, is then attached to the frame through a mount: 'mtl_crosslink_BC_to_frame'. The bell-crank part of the gel_upper_control_arm is attached to a crosslink 'ges_crosslink_uca_l', which ties in to the 'ger_crosslink_BC' and vice versa. (I've attached a picture to help visualise).
 
These crosslinks make the system 'dependent' and essentially make a double a-arm setup behave like a beam (with regards to camber). With the above in mind I have a few questions.
 
  1. Does A/Car care if links pass through each other or will it just solve the system 'mathematically'?
  2. My assembly loads, but will not statically solve when attempting to simulate OWT or PWT within the 25 MAXIT. Could this be related to Q1?
  3. By making the system 'dependent' have I created an issue for the solver?
 
As is stands the symmetric parts are lca, uca, crosslink, upright, pushrods, dampers, springs and pushrod bellcrank. The single parts are the crosslinks. The crosslinks are attached using single spherical joints, everything else uses symmetric bushinsg and joints.
 
My mounts are:
lca_to_frame
crosslink_BC_to_frame
BC_to_frame (pushrod suspension)
damper_to_frame
tierod_to_steering
 
Hopefully the above makes some sense.
 
Woz

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  • Ok, I've placed convel joints at one end of the steering tierod (inner), one end of the pushrod (inboard) and at both ends of the damper. I've matched the alignments with the fsae_2018 model too. I've also removed the second revolute joint from the upper and lower control arms as well as my additional crosslink rocker. The model loads fine with no redundant constraints, but the OWT simulation still fails. The error relates to wheel force on the testrig?
     
    I've attache error message for info.
     
    Can anyone hint at why that might be?
     
    Woz
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  • Ok, I've placed convel joints at one end of the steering tierod (inner), one end of the pushrod (inboard) and at both ends of the damper. I've matched the alignments with the fsae_2018 model too. I've also removed the second revolute joint from the upper and lower control arms as well as my additional crosslink rocker. The model loads fine with no redundant constraints, but the OWT simulation still fails. The error relates to wheel force on the testrig?
     
    I've attache error message for info.
     
    Can anyone hint at why that might be?
     
    Woz
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