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Bushing Force not being applied

Posted: Wed Feb 20, 2019 8:35 am
by cjszero
Hello everyone, I am a newbie. I defined an exoskeleton and the body's bushingforce like this, but it didn't work. What is the problem?
<BushingForce name="BackJointBushing">
<isDisabled>false</isDisabled>
<!--One of the two bodies connected by the bushing.-->
<body_1>chair_less_lower</body_1>
<!--The other of the two bodies connected by the bushing.-->
<body_2>tibia_r</body_2>
<!--Location of bushing frame on body 1.-->
<location_body_1>0.0317473 -0.105805 -0.0503612</location_body_1>
<!--Orientation of bushing frame in body 1 as x-y-z, body fixed Euler rotations.-->
<orientation_body_1>0 0 0</orientation_body_1>
<!--Location of bushing frame on body 2.-->
<location_body_2>0.0400457 -0.127228 0.0159831</location_body_2>
<!--Orientation of bushing frame in body 2 as x-y-z, body fixed Euler rotations.-->
<orientation_body_2>0 0 0</orientation_body_2>
<!--Stiffness parameters resisting relative rotation (Nm/rad).-->
<rotational_stiffness>10000 10000 10000</rotational_stiffness>
<!--Stiffness parameters resisting relative translation (N/m).-->
<translational_stiffness>100000 100000 100000</translational_stiffness>
<!--Damping parameters resisting relative angular velocity. (Nm/(rad/s))-->
<rotational_damping>100 100 100</rotational_damping>
<!--Damping parameters resisting relative translational velocity. (N/(m/s)-->
<translational_damping>0.01 0.01 0.01</translational_damping>
</BushingForce>

Re: exoskeleton

Posted: Wed Feb 20, 2019 9:53 am
by jimmy
but it didn't work
DIdn't work how? What do you use it in (IK, ID, FWD)? What did you expect and what did you get?

Re: Bushing Force not being applied

Posted: Wed Feb 20, 2019 11:45 pm
by cjszero
Thank you very much for your reply.
I designed an exoskeleton that supports the body's weight. I want to use opensim to simulate changes in muscle strength before and after wearing the exoskeleton. I have imported the exoskeleton into the opensim Leg6Dof9Musc model. Although I have defined the bushingforce between the exoskeleton and the human body, the exoskeleton is not bound to the human body and they cannot move at the same time. Do you have any good suggestions? Looking forward to your reply