Hello,
My question concerns the wrist model. I infer there is no experiment for it, and if one wants to make it functional, must do all the work going through marking the forearm, hand, recordings coordinates, fill in xml files with appropriate settings, etc - right? Or, are these available somewhere?
Thank you!
Dana
wrist model
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Sam Hamner
- Posts: 58
- Joined: Tue Jun 26, 2007 5:03 pm
RE: wrist model
Hi Dana,
The wrist model is used in Tutorial #2 to simulate a tendon transfer surgery, which came from a study by Herrmann & Delp in 1999. You can find the tutorials under the "Help" menu in OpenSim.
I am not sure what you mean by "functional" but the wrist model is used only for kinematic analysis, that is, there are no dynamic properties such as mass or inertia, associated with the model. However, SimTK includes a library of neuromuscular biomechanics models: https://simtk.org/project/xml/downloads.xml?group_id=95
Included is a full upper extremity model developed by Kate Holzbaur, which includes a more complete set of muscles for the arm and shoulder as well as mass properties. Currently it is a SIMM model, but you can import it into OpenSim using the "Import SIMM Model" option located under the "File" menu.
Cheers,
Sam Hamner
--
Graduate Student
Neuromuscular Biomechanics Lab
Stanford University
The wrist model is used in Tutorial #2 to simulate a tendon transfer surgery, which came from a study by Herrmann & Delp in 1999. You can find the tutorials under the "Help" menu in OpenSim.
I am not sure what you mean by "functional" but the wrist model is used only for kinematic analysis, that is, there are no dynamic properties such as mass or inertia, associated with the model. However, SimTK includes a library of neuromuscular biomechanics models: https://simtk.org/project/xml/downloads.xml?group_id=95
Included is a full upper extremity model developed by Kate Holzbaur, which includes a more complete set of muscles for the arm and shoulder as well as mass properties. Currently it is a SIMM model, but you can import it into OpenSim using the "Import SIMM Model" option located under the "File" menu.
Cheers,
Sam Hamner
--
Graduate Student
Neuromuscular Biomechanics Lab
Stanford University
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Kaan Divringi
- Posts: 3
- Joined: Tue Jan 27, 2009 11:10 am
RE: wrist model
Hi Sam,
Sorry for replying to your topic that's over a year old but I took a closer look at the upper extremity model developed by Kate Holzbaur and did not find any mass properties. Looking through the original paper, the methods section doesn't mention anything about defining masses in the model. I'm willing to accept that the original model never had masses in the first place, but just in case: did you come across mass properties for this model in some other context?
Sorry for replying to your topic that's over a year old but I took a closer look at the upper extremity model developed by Kate Holzbaur and did not find any mass properties. Looking through the original paper, the methods section doesn't mention anything about defining masses in the model. I'm willing to accept that the original model never had masses in the first place, but just in case: did you come across mass properties for this model in some other context?
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Domenico CAMPOLO
- Posts: 1
- Joined: Tue Feb 16, 2010 7:43 am
RE: wrist model
Hi,
I'm new to OpenSIM and I would be very interested in simulations of the wrist/upper limb dynamics.
At this moment, I'm interested in 'synthetic motion', so I would like to pre-determine the kinematics of each joint (without using markers and motion-capture data).
My understanding it that I can create a .mot file with various columns, the first being time and the rest all the names listed in GENCOORDS section of the joint file.
Is this correct?
At least it seems to work for the arm26 model (that comes with OpenSIM) as it generates an InverseDynamics .sto files that makes sense.
When I try with the 'Wrist' or the 'Upper Extremity' models I got strange results such as 1.#QNAN000000000000000 values for the moments.
From your posts, it seems to be clearly due to the lack of mass properties in the original model.
Since I cannot find any updated model (with masses), I have tried adding manually some mass properties here and there (the main segments: humerus, ulna, radius) but nothing seems to change.
I would be grateful for any suggestion.
Thanks very much for your attention,
Domenico
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Domenico (mimmo) CAMPOLO
School of Mechanical & Aerospace Engineering
Nanyang Technological University - Singapore
I'm new to OpenSIM and I would be very interested in simulations of the wrist/upper limb dynamics.
At this moment, I'm interested in 'synthetic motion', so I would like to pre-determine the kinematics of each joint (without using markers and motion-capture data).
My understanding it that I can create a .mot file with various columns, the first being time and the rest all the names listed in GENCOORDS section of the joint file.
Is this correct?
At least it seems to work for the arm26 model (that comes with OpenSIM) as it generates an InverseDynamics .sto files that makes sense.
When I try with the 'Wrist' or the 'Upper Extremity' models I got strange results such as 1.#QNAN000000000000000 values for the moments.
From your posts, it seems to be clearly due to the lack of mass properties in the original model.
Since I cannot find any updated model (with masses), I have tried adding manually some mass properties here and there (the main segments: humerus, ulna, radius) but nothing seems to change.
I would be grateful for any suggestion.
Thanks very much for your attention,
Domenico
------
Domenico (mimmo) CAMPOLO
School of Mechanical & Aerospace Engineering
Nanyang Technological University - Singapore