Search found 81 matches

by David John Saxby
Wed Oct 23, 2013 4:47 am
Forum: OpenSim
Topic: Displacement of reference frames
Replies: 5
Views: 1259

Re: Displacement of reference frames

Hi Spencer, I'm not sure which model of the lower limb you are using, but many models include a knee joint that is composed of n rotational dof's and two splines (ant/post and superior/inferior) coupled to the flexion or first rotation of the knee. The combination of free rotation and coupled spline...
by David John Saxby
Sun Sep 22, 2013 12:34 am
Forum: OpenSim
Topic: Scale a Model with a Script
Replies: 3
Views: 823

Re: Scale a Model with a Script

Hey Ursula, I would be careful using Matlab to parse, edit, compile xml's for execution in OpenSim. I don't know the exact reason for this, but OpenSim does not provide a grammar for the xml's it uses, so you are guessing a bit when you edit/create them. This leads to problems with command line exec...
by David John Saxby
Wed Sep 18, 2013 11:50 am
Forum: OpenSim
Topic: Full body model and opening problems.
Replies: 1
Views: 220

Re: Full body model and opening problems.

Hi,

Check that your system path includes the OpenSim bin (where the .dll's are located).

The path will be ('Where you installed OpenSim"\OpenSim 3.01\bin).

It sounds like this may not be in your system path. If not, add the above path to variable list.

David
by David John Saxby
Sat Aug 31, 2013 9:55 pm
Forum: OpenSim
Topic: Scaling problem - RASI & LASIS issue
Replies: 3
Views: 708

Re: Scaling problem - RASI & LASIS issue

Hi KT, Regarding the java error I am not totally sure. I believe though that you must tick the scale model box for the model adjuster to run. I think this is due to some requirements in the cost function that the adjust markers uses. The Osim developers would know why. Its not a problem though, you ...
by David John Saxby
Wed Aug 28, 2013 9:33 pm
Forum: OpenSim
Topic: Scaling problem - RASI & LASIS issue
Replies: 3
Views: 708

Re: Scaling problem - RASI & LASIS issue

Hi, You are describing a common problem. Scaling is performed by applying a scale factor to the body by dimension or uniformly across dimensions. You could determine the virtual marker positions in your generic/unscaled model, and compare this with your experimentally measured inter-ASIS to determin...
by David John Saxby
Thu Aug 15, 2013 3:53 pm
Forum: OpenSim
Topic: OpenSim 3.1 - Specifying log file location
Replies: 5
Views: 808

Re: OpenSim 3.1 - Specifying log file location

Hi Shaun,

That is also how my code runs. Some the API execution commands (maybe all not sure) require the path to the directory as input argument. While the write location doesn't seem modifiable, so it probably uses the cd as default.

Glad its working

David
by David John Saxby
Mon Aug 12, 2013 2:51 am
Forum: OpenSim
Topic: OpenSim 3.1 - Specifying log file location
Replies: 5
Views: 808

Re: OpenSim 3.1 - Specifying log file location

Hi Shaun,

Are you running Windows 7? Are you running Matlab in Administrator mode? I think the permissions might be different between operating systems, not sure though.

David
by David John Saxby
Wed Aug 07, 2013 5:37 pm
Forum: OpenSim
Topic: OpenSim 3.1 - Specifying log file location
Replies: 5
Views: 808

Re: OpenSim 3.1 - Specifying log file location

Hi Shaun, I had a similar issue. I wanted to write the log file for each given operation, rather than overwrite. What I did was (see below example from a scaling operation): % Check for the log file test4linscalelog = dir(fullfile(subjectDir, '*out.log')); % Condition for copying log if ~isempty(tes...
by David John Saxby
Thu Jul 11, 2013 7:39 pm
Forum: OpenSim
Topic: Markerset influence on Scaling results
Replies: 3
Views: 1007

Re: Markerset influence on Scaling results

Hi Alice, A range of marker sets are possible, with IK allowing fewer markers than that required in segment based modelling but also permitting redundant marker sets where IK solves an over determined problem. For both scaling and IK, I would say the issue is going to be the fidelity between your vi...
by David John Saxby
Tue Jul 09, 2013 9:01 pm
Forum: OpenSim
Topic: muscle analysis vs direct API computation
Replies: 3
Views: 646

Re: muscle analysis vs direct API computation

Hi All,

To update:

Success with direct computation of muscle lengths and moment arms, the outputs now match the analyze API exactly.

Thanks very much for the help,

David