Object slips from gripper fingers when grasping in simulation

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Hi every one,

I am really getting frustrated with this problem. I have a Gazebo simulation of a KUKA_KR6R900SIXX with a gripper and an object to grasp. The issue is that every time i try to grasp the object, it slips between the fingers of the gripper. I can see the contacts established in Gazebo (see video) but it is like there is no friction between the object and the gripper fingers. What parameters should i fix to make the cylinder stick the gripper. See video here : Kuka_gripper_Gazebo_Sim

Here is my configuration :

1) The gripper fingers link xacro config :

  <joint
    name="Mors_prismatic1_joint"
    type="prismatic">
    <origin
      xyz="0.0014158 -0.020952 0.0995"
      rpy="1.5708 0 0.5236" />
    <parent
      link="${prefix}tool0" />
    <child
      link="Mors_prismatic1_Link" />
    <axis
      xyz="0 0 1" />
    <limit effort="1000" lower="0.0" upper="0.02" velocity="0.01" />
    <dynamics damping="0.7" />
    <dynamics damping="1" friction="1"/>
  </joint>

  <joint
    name="Mors_prismatic2_joint"
    type="prismatic">
    <origin
      xyz="0.017437 0.011702 0.0995"
      rpy="1.5708 0 2.618" />
    <parent
      link="${prefix}tool0" />
    <child
      link="Mors_prismatic2_Link" />
    <axis
      xyz="0 0 1" />
    <limit effort="1000" lower="0.0" upper="0.02" velocity="0.01" />
    <dynamics damping="0.7" />
    <dynamics damping="1" friction="1"/>
  </joint>

  <joint
    name="Mors_prismatic3_joint"
    type="prismatic">
    <origin
      xyz="-0.018853 0.00925 0.0995"
      rpy="1.5708 0 -1.5708" />
    <parent
      link="${prefix}tool0" />
    <child
      link="Mors_prismatic3_Link" />
    <axis
      xyz="0 0 1" />
    <limit effort="1000" lower="0.0" upper="0.02" velocity="0.01" />
    <dynamics damping="0.7" />
    <dynamics damping="1" friction="1"/>
  </joint>

2)The gripper fingers gazebo xacro config :

  <gazebo reference="Mors_prismatic1_Link">
    <material>Gazebo/Blue</material>
    <turnGravityOff>true</turnGravityOff>
    <implicitSpringDamper>1</implicitSpringDamper>
    <kp>100000.0</kp>
    <kd>1.0</kd>
    <mu1>10.0</mu1>
    <mu2>0.1</mu2>
    <fdir1>1 0 0</fdir1>
    <minDepth>0.01</minDepth>
  </gazebo>

  <gazebo reference="Mors_prismatic2_Link">
    <material>Gazebo/Blue</material>
    <turnGravityOff>true</turnGravityOff> 
    <implicitSpringDamper>1</implicitSpringDamper>
    <kp>100000.0</kp>
    <kd>1.0</kd>
    <mu1>10.0</mu1>
    <mu2>0.1</mu2>
    <fdir1>1 0 0</fdir1>
    <minDepth>0.01</minDepth>
  </gazebo>



  <gazebo reference="Mors_prismatic3_Link">
    <material>Gazebo/Blue</material>
    <turnGravityOff>true</turnGravityOff>
    <implicitSpringDamper>1</implicitSpringDamper>
    <kp>100000.0</kp>
    <kd>1.0</kd>
    <mu1>10.0</mu1>
    <mu2>0.1</mu2>
    <fdir1>1 0 0</fdir1>
    <minDepth>0.01</minDepth>
  </gazebo>

3)The object (cylinder) urdf :

<?xml version="1.0"?>
<robot
  name="Cylinder">
  <link
    name="cylinder_link">
    <inertial>
      <origin
        xyz="-2.27623991509391E-49 1.09168197518227E-17 0.0125"
        rpy="0 0 0" />
      <mass
        value="0.12556160438235" />
      <inertia
        ixx="0"
        ixy="0"
        ixz="0"
        iyy="0"
        iyz="0"
        izz="0" />
    </inertial>
    <visual>
      <origin
        xyz="0 0 0"
        rpy="0 0 0" />
      <geometry>
        <mesh
          filename="package://Cylinder/meshes/base_link.STL" />
      </geometry>
      <material
        name="">
        <color
          rgba="0.647058823529412 0.619607843137255 0.588235294117647 1" />
      </material>
    </visual>
    <collision>
      <origin
        xyz="0 0 0"
        rpy="0 0 0" />
      <geometry>
        <mesh
          filename="package://Cylinder/meshes/base_link.STL" />
      </geometry>
    </collision>
  </link>

  <gazebo reference="cylinder_link">
    <implicitSpringDamper>1</implicitSpringDamper>
    <kp>100000.0</kp>
    <kd>1.0</kd>
    <mu1>10.0</mu1>
    <mu2 ...