Point Constraint for Kinematics
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Eva Maddox
- Posts: 1
- Joined: Thu Nov 15, 2018 3:24 pm
Point Constraint for Kinematics
Has anyone implemented a point constraint on the toes of a model before running inverse kinematics? The model keeps sending the toes through the ground instead of bending more at the knees and hips.
Tags:
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Carmichael Ong
- Posts: 401
- Joined: Fri Feb 24, 2012 11:50 am
Re: Point Constraint for Kinematics
It sounds like you could first try different marker tracking weights in IK.
- Does it look like the experimental marker data for the toes actually goes into the ground? If so, then you might not trust the toe markers as much as weight them lower than the hip and knees that you might trust more.
- Do the experimental marker data for the toes look correct relative to the ground, but your IK solution doesn't track the foot well? Consider increasing the weights on the foot markers to track them better.
One other note: The floor in OpenSim is drawn roughly at y = 0 for visualization purposes. It would be good to check that your experimental setup also has the floor at y = 0, and if it doesn't, adjust accordingly.
- Does it look like the experimental marker data for the toes actually goes into the ground? If so, then you might not trust the toe markers as much as weight them lower than the hip and knees that you might trust more.
- Do the experimental marker data for the toes look correct relative to the ground, but your IK solution doesn't track the foot well? Consider increasing the weights on the foot markers to track them better.
One other note: The floor in OpenSim is drawn roughly at y = 0 for visualization purposes. It would be good to check that your experimental setup also has the floor at y = 0, and if it doesn't, adjust accordingly.