SimTK: OpenSim: [#1715] changing orientations of weld_constraint femur_sensor/femur does not update/behave properly

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Date:
2012-08-23 23:40

Priority:
3

State:
Open

Submitted by:
Mark Finch (mfin032)

Assigned to:
Michael Sherman (sherm)

Summary:
changing orientations of weld_constraint femur_sensor/femur does not update/behave properly - especially sign changes.

Detailed description
changing orientations of weld_constraint femur_sensor/femur does not update/behave properly - especially sign changes.
changing orientations of weld_constraint femur_sensor/femur does not update/behave properly - especially sign changes.

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Date: 2012-10-20 04:50 Sender: Michael Sherman The problem is that the orientation constraint equations used for the Weld constraint in Simbody are satisified when the axes are parallel or antiparallel. For assembly they depend on the initial conditions being closer to parallel. Until this is fixed, the best workaround is to make sure that your initial conditions are set so that Weld constraints are oriented in roughly the right direction (say within 60 degrees) prior to the start of an assembly or IK run.
Date: 2012-10-20 02:09 Sender: Ayman Habib This's the assembly problem in Simbody where axes can be opposing but assembly succeeds.. -Ayman

Field	Old Value	Date	By
resolution_id	100	2012-10-20 04:50	sherm
assigned_to	aymanh	2012-10-20 02:09	aymanh

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