Problem with propellers rotating around middle of robot.
I am making a quadcopter and the propellers are rotating around the center of the robot. I am trying to get the propellers to be stationary and just rotate in place. I have added some pictures of before and during rotation to show the problem. Below is the code I am using. Any help would be appreciated.
<?xml version="1.0"?>
<robot name="drone">
<material name="magenta">
<color rgba="1 .1 .85 1"/>
</material>
<link name="dummy">
</link>
<link name="base_link">
<inertial>
<origin xyz="0 0 0" rpy="0 0 0"/>
<mass value="1" />
<inertia ixx="0.0" ixy="0.0" ixz="0.0" iyy="0.0" iyz="0.0" izz="0.0"/>
</inertial>
<collision>
<origin xyz="0 0 0" rpy="0 0 0"/>
<geometry>
<box size="0.5 0.5 0.5"/>
</geometry>
</collision>
<visual>
<origin rpy="0.0 0 0" xyz="0 0 0"/>
<geometry>
<box size="0.2 0.2 0.1"/>
</geometry>
<material name="magenta"/>
</visual>
</link>
<link name="propeller_M1_link">
<inertial>
<origin rpy="0.0 0 0" xyz="0.25 0 0.0422"/>
<mass value="0.1" />
<inertia ixx="0.0" ixy="0.0" ixz="0.0" iyy="0.0" iyz="0.0" izz="0.0"/>
</inertial>
<collision>
<origin rpy="0.0 0 0" xyz="0.25 0 0.0422"/>
<geometry>
<cylinder radius="0.06" length="0.0324"/>
</geometry>
<material name="magenta"/>
</collision>
<visual>
<origin rpy="0.0 0 0" xyz="0.25 0 0.0422"/>
<geometry>
<cylinder radius="0.06" length="0.0324"/>
</geometry>
<material name="magenta"/>
</visual>
</link>
<link name="arm_M1_link">
<inertial>
<origin xyz="0 0 0" rpy="0 0 0"/>
<mass value="0.18" />
<inertia ixx="0.0" ixy="0.0" ixz="0.0" iyy="0.0" iyz="0.0" izz="0.0"/>
</inertial>
<collision>
<origin rpy="0 0 0" xyz="0.175 0 0"/>
<geometry>
<box size="0.15 0.05 0.05"/>
</geometry>
<material name="magenta"/>
</collision>
<visual>
<origin rpy="0 0 0" xyz="0.175 0 0"/>
<geometry>
<box size="0.15 0.05 0.05"/>
</geometry>
<material name="magenta"/>
</visual>
</link>
<link name="motor_M1_link">
<inertial>
<origin rpy="0.0 0 0" xyz="0.25 0 0.0255"/>
<mass value="0.1" />
<inertia ixx="0.0" ixy="0.0" ixz="0.0" iyy="0.0" iyz="0.0" izz="0.0"/>
</inertial>
<collision>
<origin rpy="0.0 0 0" xyz="0.25 0 0.0255"/>
<geometry>
<cylinder radius="0.006" length="0.001"/>
</geometry>
<material name="magenta"/>
</collision>
<visual>
<origin rpy="0.0 0 0" xyz="0.25 0 0.0255"/>
<geometry>
<cylinder radius="0.006" length="0.001"/>
</geometry>
<material name="magenta"/>
</visual>
</link>
<link name="propeller_M2_link">
<inertial>
<origin rpy="0 0 0" xyz="-0.25 0 0.0422"/>
<inertia ixx="0.0" ixy="0.0" ixz="0.0" iyy="0.0" iyz="0.0" izz="0.0"/>
<mass value="0.1"/>
</inertial>
<collision>
<origin rpy="0 0 0" xyz="-0.25 0 0.0422"/>
<geometry>
<cylinder radius="0.06" length="0.0324"/>
</geometry>
<material name="magenta"/>
</collision>
<visual ...