Error in using CMC and ForwardTool in Upper limb model

[Alex Priamikov]

Good day,

I'm trying to use CMC and Forward tool for UpperLowerBodySimple model.

But I got an error java.lang.RuntimeException: SimTK Exception thrown at SmallMatrixMixed.h:878:
Error detected by Simbody method lapackInverse(Mat<>): Matrix is singular so can't be inverted (Lapack getrf info=3).
(Required condition 'info==0' was not met.)

at org.opensim.modeling.opensimModelJNI.OpenSimContext_getActivation(Native Method)
at org.opensim.modeling.OpenSimContext.getActivation(OpenSimContext.java:173)
at org.opensim.view.MuscleColorByActivationFunction.getColor(MuscleColorByActivationFunction.java:23)
at org.opensim.view.LineSegmentMuscleDisplayer.updateGeometry(LineSegmentMuscleDisplayer.java:180)
at org.opensim.view.LineSegmentMuscleDisplayer.setApplyColoringFunction(LineSegmentMuscleDisplayer.java:80)
at org.opensim.view.SingleModelVisuals.setApplyMuscleColors(SingleModelVisuals.java:345)
at org.opensim.view.motions.MotionDisplayer.setupMotionDisplay(MotionDisplayer.java:277)
at org.opensim.view.motions.MotionDisplayer.<init>(MotionDisplayer.java:229)
at org.opensim.view.motions.JavaMotionDisplayerCallback.<init>(JavaMotionDisplayerCallback.java:113)
at org.opensim.tracking.ForwardToolModel$ForwardToolWorker.<init>(ForwardToolModel.java:107)
at org.opensim.tracking.ForwardToolModel.execute(ForwardToolModel.java:375)
at org.opensim.tracking.AnalyzeAndForwardToolPanel.pressedApply(AnalyzeAndForwardToolPanel.java:619)
at org.opensim.tracking.BaseToolPanel.actionPerformed(BaseToolPanel.java:130)
at org.netbeans.core.windows.services.NbPresenter$ButtonListener.actionPerformed(NbPresenter.java:1327)
at javax.swing.AbstractButton.fireActionPerformed(AbstractButton.java:1995)
at javax.swing.AbstractButton$Handler.actionPerformed(AbstractButton.java:2318)
at javax.swing.DefaultButtonModel.fireActionPerformed(DefaultButtonModel.java:387)
at javax.swing.DefaultButtonModel.setPressed(DefaultButtonModel.java:242)
at javax.swing.plaf.basic.BasicButtonListener.mouseReleased(BasicButtonListener.java:236)
at java.awt.Component.processMouseEvent(Component.java:6288)
at javax.swing.JComponent.processMouseEvent(JComponent.java:3267)
at java.awt.Component.processEvent(Component.java:6053)
at java.awt.Container.processEvent(Container.java:2041)
at java.awt.Component.dispatchEventImpl(Component.java:4651)
at java.awt.Container.dispatchEventImpl(Container.java:2099)
at java.awt.Component.dispatchEvent(Component.java:4481)
at java.awt.LightweightDispatcher.retargetMouseEvent(Container.java:4577)
at java.awt.LightweightDispatcher.processMouseEvent(Container.java:4238)
at java.awt.LightweightDispatcher.dispatchEvent(Container.java:4168)
at java.awt.Container.dispatchEventImpl(Container.java:2085)
at java.awt.Window.dispatchEventImpl(Window.java:2478)
at java.awt.Component.dispatchEvent(Component.java:4481)
at java.awt.EventQueue.dispatchEventImpl(EventQueue.java:643)
at java.awt.EventQueue.access$000(EventQueue.java:84)
at java.awt.EventQueue$1.run(EventQueue.java:602)
at java.awt.EventQueue$1.run(EventQueue.java:600)
at java.security.AccessController.doPrivileged(Native Method)
at java.security.AccessControlContext$1.doIntersectionPrivilege(AccessControlContext.java:87)
at java.security.AccessControlContext$1.doIntersectionPrivilege(AccessControlContext.java:98)
at java.awt.EventQueue$2.run(EventQueue.java:616)
at java.awt.EventQueue$2.run(EventQueue.java:614)
at java.security.AccessController.doPrivileged(Native Method)
at java.security.AccessControlContext$1.doIntersectionPrivilege(AccessControlContext.java:87)
at java.awt.EventQueue.dispatchEvent(EventQueue.java:613)
at org.netbeans.core.TimableEventQueue.dispatchEvent(TimableEventQueue.java:148)
[catch] at java.awt.EventDispatchThread.pumpOneEventForFilters(EventDispatchThread.java:269)
at java.awt.EventDispatchThread.pumpEventsForFilter(EventDispatchThread.java:184)
at java.awt.EventDispatchThread.pumpEventsForHierarchy(EventDispatchThread.java:174)
at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:169)
at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:161)
at java.awt.EventDispatchThread.run(EventDispatchThread.java:122)

How can I fix it, or also maybe could you provide some data and settings files(if I'm not using the right one)?

Best,
Alex

[Ayman Habib]

Hi Alex,

As the stacktrace indicates, the exception you ran into occurs trying to color the muscles using Activations. Reason you get this singularity could be that the muscles are not initialized properly, or external loads not applied correctly leading to very large forces and infinite accelerations. Other possible culprit would be missing mass properties which you need to full specify if you're running CMC and/or ForwardTool.

Hope this helps,
-Ayman

[Alex Priamikov]

Hi Ayman

Can it also occur, because I disabled some muscles and blocked some angles?
Also can you provide example configuration for this model?

Best regards,
Alex

[Alex Priamikov]

I figure out that I don't have mass properties for my bodies, think the problem comes from this side.