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### Slow strong prismatic joint

Hi.

I'm having some problems modelling a slow and strong prismatic joint (real world screw joint). The problem seems to be that <velocity> is not being considered.

My joint looks like:

<xacro:macro name="small_extender" params="name rot:=1">
<xacro:small_ext name="${name}_inner" /> <xacro:small_ext2 name="${name}_outer" rot="${rot}" /> <joint name="${name}" type="prismatic">
<parent link="${name}_inner" /> <child link="${name}_outer" />
<axis xyz="0 0 1" />
<origin xyz="0 0 ${small_ext_height - 0.026}" /> <limit lower="-0.025" upper="0.0" effort="100.0" velocity="0.00045" /> <dynamics damping="1.0" friction="80" /> </joint> <gazebo reference="${name}">
<implicitSpringDamper>1</implicitSpringDamper>
</gazebo>
</xacro:macro>


And I'm controlling the joint through a Gazebo plugin that uses JointController and a position PID with SetPositionTarget. Currently I'm using <pid>10000.0 0 0 </pid> for parameters because the distance is quite small. When I set a position target for this joint it moves a lot faster than the <velocity> tag indicates, and it seems to be the case however I tune the PID. The rest of the robot should have the correct masses so I don't think that is the problem.