Test ball joints

Author: javizqh

CustomRobots/turtlebot3/launch/turtlebot3.launch.py

@@ -31,25 +31,25 @@ def launch_setup(context):
     # =========================
     # ROBOT DESCRIPTION (URDF)
     # =========================
-    # xacro_file = os.path.join(
-    #     package_dir,
-    #     "model",
-    #     "turtlebot3",
-    #     "turtlebot3.urdf.xacro",
-    # )
-
-    # robot_description_content = xacro.process_file(
-    #     xacro_file,
-    #     mappings={
-    #         "camera": "true" if sensor == "camera" else "false",
-    #         "noise_level": gz_noise.perform(context),
-    #     },
-    # ).toxml()
+    xacro_file = os.path.join(
+        package_dir,
+        "model",
+        "turtlebot3",
+        "turtlebot3.urdf.xacro",
+    )
+
+    robot_description_content = xacro.process_file(
+        xacro_file,
+        mappings={
+            "camera": "true" if sensor == "camera" else "false",
+            "noise_level": gz_noise.perform(context),
+        },
+    ).toxml()
 
     ## Temporary SDF load
-    sdf_file = os.path.join(package_dir, 'models', 'turtlebot3', 'turtlebot3.sdf')
-    with open(sdf_file, 'r') as infp:
-        robot_description_content = infp.read()
+    # sdf_file = os.path.join(package_dir, 'models', 'turtlebot3', 'turtlebot3.sdf')
+    # with open(sdf_file, 'r') as infp:
+    #     robot_description_content = infp.read()
 
     robot_description = {"robot_description": robot_description_content}
 

CustomRobots/turtlebot3/models/turtlebot3/turtlebot3_common.urdf.xacro

@@ -140,60 +140,6 @@
       </visual>
     </link>
 
-    <link name="caster_back_right_link">
-      <origin rpy="-1.57 0 0" xyz="-0.177 -0.064 -0.004"/>
-      <inertial>
-        <mass value="0.001"/>
-        <inertia ixx="0.00001" ixy="0" ixz="0" iyy="0.00001" iyz="0" izz="0.00001"/>
-      </inertial>
-      <collision>
-        <geometry>
-          <sphere radius="0.005"/>
-        </geometry>
-        <gazebo>
-          <surface>
-            <contact>
-              <ode>
-                <soft_cfm>0</soft_cfm>
-                <soft_erp>0.2</soft_erp>
-                <kp>1e+5</kp>
-                <kd>1</kd>
-                <max_vel>0.01</max_vel>
-                <min_depth>0.001</min_depth>
-              </ode>
-            </contact>
-          </surface>
-        </gazebo>
-      </collision>
-    </link>
-
-    <link name="caster_back_left_link">
-      <origin rpy="-1.57 0 0" xyz="-0.177 0.064 -0.004"/>
-      <inertial>
-        <mass value="0.001"/>
-        <inertia ixx="0.00001" ixy="0" ixz="0" iyy="0.00001" iyz="0" izz="0.00001"/>
-      </inertial>
-      <collision>
-        <geometry>
-          <sphere radius="0.005"/>
-        </geometry>
-        <gazebo>
-          <surface>
-            <contact>
-              <ode>
-                <soft_cfm>0</soft_cfm>
-                <soft_erp>0.2</soft_erp>
-                <kp>1e+5</kp>
-                <kd>1</kd>
-                <max_vel>0.01</max_vel>
-                <min_depth>0.001</min_depth>
-              </ode>
-            </contact>
-          </surface>
-        </gazebo>
-      </collision>
-    </link>
-
     <link name="camera_link"/>
 
     <joint name="base_to_base_link" type="fixed">
@@ -227,18 +173,48 @@
     </joint>
 
     <!-- Ball joints -->
-    <joint name="caster_back_right_joint" type="continuous">
+    <joint name="caster_back_left_joint" type="fixed">
       <parent link="base_link"/>
-      <child link="caster_back_right_link"/>
-      <limit effort="20" velocity="100"/>
+      <child link="caster_back_left_link"/>
+      <origin xyz="-0.177 0.064 -0.004" rpy="-1.57 0 0"/>
     </joint>
 
-    <joint name="caster_back_left_joint" type="continuous">
+    <link name="caster_back_left_link">
+      <collision>
+        <origin xyz="0 0.001 0" rpy="0 0 0"/>
+        <geometry>
+          <box size="0.030 0.009 0.020"/>
+        </geometry>
+      </collision>
+
+      <inertial>
+        <origin xyz="0 0 0" />
+        <mass value="0.005" />
+        <inertia ixx="0.001" ixy="0.0" ixz="0.0" iyy="0.001" iyz="0.0" izz="0.001" />
+      </inertial>
+    </link>
+
+    <joint name="caster_back_right_joint" type="fixed">
       <parent link="base_link"/>
-      <child link="caster_back_left_link"/>
-      <limit effort="20" velocity="100"/>
+      <child link="caster_back_right_link"/>
+      <origin xyz="-0.177 -0.064 -0.004" rpy="-1.57 0 0"/>
     </joint>
 
+    <link name="caster_back_right_link">
+      <collision>
+        <origin xyz="0 0.001 0" rpy="0 0 0"/>
+        <geometry>
+          <box size="0.030 0.009 0.020"/>
+        </geometry>
+      </collision>
+
+      <inertial>
+        <origin xyz="0 0 0" />
+        <mass value="0.005" />
+        <inertia ixx="0.001" ixy="0.0" ixz="0.0" iyy="0.001" iyz="0.0" izz="0.001" />
+      </inertial>
+    </link>
+
     <xacro:imu parent="imu_link" topic="turtlebot3/imu" xyz="-0.032 0 0.068" rpy="0 0 0"/>
     <xacro:lidar xyz="-0.064 0 0.121" rpy="0 0 0" name="lidar" parent="base_link" topic="turtlebot3/laser/scan"/>
     <xacro:velocity topic="turtlebot3/cmd_vel"/>