[Bug]: Constraint_models are not updated when building a reduced model

[aled96]

Hello,

I have imported an SDF robot model with a closed loop chain, this correctly generates the model with the associated constraint_models.

Now, I have to lock some joints with the buildReducedModel. However, this creates a misalignment with the constraint_models previously built since those are not updated according to the model reduction.

Is there a method to do this automatically or do I have to update the constraint_models by hand?

Thanks

pinocchio::sdf::buildModel(model_path, JointModelFreeFlyer(), model,  constraint_models);

// Get homing configuration of the full model
q0_full = neutral(model);

// Get list_of_joints_to_lock_by_id

// Build reduced model
buildReducedModel(model, list_of_joints_to_lock_by_id, q0_full, reduced_model);

[jorisv]

Hello,
Currently there is no method to do that. You have to do it manually.
The current constraint API will be discontinued in Pinocchio 4 and replaced by a more generic one.
You can turn this bug report into a feature request, so we could work on this kind of algorithm in Pinocchio 4.