Search found 24 matches

by Daniel Krueger
Wed Aug 10, 2016 5:14 am
Forum: OpenSim
Topic: Importing a CAD Model Into OpenSim
Replies: 2
Views: 580

Re: Importing a CAD Model Into OpenSim

Kathleen, what CAD-system do you use? I developed an extension for CREO (Pro/Engineer) that can convert open chain mechanisms to OpenSim multibody models. Please contact me if you want me to convert your assembly.
Daniel
by Daniel Krueger
Tue Apr 12, 2016 1:23 am
Forum: OpenSim
Topic: Decorative Geometry in GUI
Replies: 2
Views: 395

Re: Decorative Geometry in GUI

Thanks Ayman,
I think I' ll just wait for the 4.0 release. Since I have some students working with my models It wouldn't make sense to let them work with a pre-release. So we stick with 3.2.
At least I know that my implementation is correct.
Regards,
Daniel
by Daniel Krueger
Mon Apr 11, 2016 10:06 am
Forum: OpenSim
Topic: Decorative Geometry in GUI
Replies: 2
Views: 395

Decorative Geometry in GUI

Hi all, I recently implemented a custom force model component and implemented the ModelComponent method "generateDecorations()" to visualize my force within the GUI. However the decorations only show up within the OpenSim visualizer. The GUI seems to ignore them. Is there an alternative way to equip...
by Daniel Krueger
Sun Nov 08, 2015 6:01 am
Forum: Simbody: SimTK multibody dynamics API
Topic: sensitivity of jacobian transpose force mapping
Replies: 1
Views: 326

sensitivity of jacobian transpose force mapping

Hi all, I am working on an inverse kinematics solution that accounts for static equilibrium conditions. The goal is to find system configurations q that a) satisfy several kinematic tasks (e.g. reaching for an object) b) allow the system to be in static equilibrium meaning that in mobility space all...
by Daniel Krueger
Mon May 11, 2015 4:32 am
Forum: Simbody: SimTK multibody dynamics API
Topic: Constraint forces and implementation
Replies: 3
Views: 555

Re: Constraint forces and implementation

Ok, and here what I did with it so far: We are currently working on a project dealing with FEA simulations of human bones. Therefore we want to use force boundary conditions obtained from OpenSim models. This includes all muscle forces, joint reactions and constraint forces directly applied to a bod...
by Daniel Krueger
Mon May 11, 2015 4:09 am
Forum: Simbody: SimTK multibody dynamics API
Topic: Constraint forces and implementation
Replies: 3
Views: 555

Re: Constraint forces and implementation

This is Sherm's reply: 1) The Constraint base class methods can only deal with features common to all constraints, but a "point of application" only makes sense for certain constraints. Some constraints act on joint axes rather than bodies (couplers), some apply pure torques to bodies (orientation c...
by Daniel Krueger
Mon May 11, 2015 4:08 am
Forum: Simbody: SimTK multibody dynamics API
Topic: Constraint forces and implementation
Replies: 3
Views: 555

Constraint forces and implementation

The following two questions on Simbodys kinematic constraints were originally discussed between Sherm an me. However since others might be interested as well, I start this new topic: 1) In Simbody a constraint provides the method Constraint:getConstraintForcesAsVectors() to obtain the corresponding ...
by Daniel Krueger
Fri Oct 31, 2014 1:57 am
Forum: OpenSim
Topic: Kinect as input for model/motion
Replies: 4
Views: 1877

Re: Kinect as input for model/motion

Hello Everyone, we created a software to record motion sequences to opensim using the kinect device. It is not as easy as one might think. Since the KINECT SDK only gives you the spatial orientations of limbs as a rotation matrix, you have to determine the joint angles by decomposing this matrix int...
by Daniel Krueger
Thu Oct 23, 2014 2:48 am
Forum: OpenSim
Topic: any function to calc position of a point rel to ground?
Replies: 4
Views: 1546

Re: any function to calc position of a point rel to ground?

Hey Sina,
there is a more direct way of transforming the coordinates from a local cos to the global "ground" cos.
Take a look at the method: model.getSimbodyEngine().transformPosition(..)
Best Regards,
Daniel
by Daniel Krueger
Mon Oct 20, 2014 7:44 am
Forum: OpenSim
Topic: CMC results on "free" motions reasonable?
Replies: 1
Views: 930

CMC results on "free" motions reasonable?

Hi everyone, my colleague and me were currently discussing about CMC simulations. Out of curiosity I created a model of a simple 1-DOF pendulum with a coordinate actuator assigned to the pivot. We simulated 0.5 seconds of free swinging motion using the forward dynamic tool. Free means no excitation ...