# How to set SDF 1.4 surface properties in URDF

Hi all,

Can anybody tell me how to set the following SDF 1.4 parameters,

<surface>

<bounce>
<restitution_coefficient>
<threshold>
</bounce>

<friction>
<ode>
<mu>
<mu2>
<fdir1>
<slip1>
<slip2>
</ode>
</friction>

<contact>
<collide_without_contact>
<ode>
<soft_cfm>
<soft_erp>
<kp>
<kd>
<max_vel>
<min_depth>
</ode>
</contact>

</surface>


using a URDF (or xacro) file.

By the way, why does link gives a somewhat different set of parameters?