xacro机器人模型文件转urdf文件怎么编写launch文件启动gazebo仿真和在rviz2内显示模型

urdf文件很直白，每个零件的</link>  </joint>都要编写一遍，每个零件数据都要自己算出来结果，很麻烦，但是用起来很简单。xacro写的模型文件可以把好多常量提前定义出来，不同大小的机器人只要只要改一下常量，机器人模型就可以重新生成，代码可以复用，编写起来简单多了，但是编写launch启动文件麻烦一些。

urdf编写的小车模型文件：

1.  
   <!-- base.urdf -->
2.  
   <?xml version="1.0" ?>
3.  
   <robot name="jtbot">
4.  
   <!-- 机器人底盘 -->
5.  
   <link name="base_link">
6.  
   <visual>
7.  
   <geometry>
8.  
   <box size="0.46 0.46 0.11"/>
9.  
   </geometry>
10.  
    <material name="Cyan">
11.  
    <color rgba="0 1.0 1.0 1.0"/>
12.  
    </material>
13.  
    </visual>
14.  
    <!-- 碰撞区域 -->
15.  
    <collision>
16.  
    <geometry>
17.  
    <box size="0.46 0.46 0.11"/>
18.  
    </geometry>
19.  
    </collision>
20.  
    <inertial>
21.  
    <origin rpy="1.5707963267948966 0 1.5707963267948966" xyz="0 0 0"/>
22.  
    <mass value="15"/>
23.  
    <inertia ixx="0.279625" ixy="0.0" ixz="0.0" iyy="0.529" iyz="0.0" izz="0.279625"/>
24.  
    </inertial>
25.  
    </link>
26.  
    <!-- 机器人 Footprint -->
27.  
    <link name="base_footprint"/>
28.  
    <!-- 底盘关节 -->
29.  
    <joint name="base_joint" type="fixed">
30.  
    <parent link="base_link"/>
31.  
    <child link="base_footprint"/>
32.  
    <origin rpy="0 0 0" xyz="0.0 0.0 -0.1325"/>
33.  
    </joint>
34.  
    <link name="left_wheel_link">
35.  
    <visual>
36.  
    <origin rpy="1.5707963267948966 0 0" xyz="0 0 0"/>
37.  
    <geometry>
38.  
    <cylinder length="0.06" radius="0.0775"/>
39.  
    </geometry>
40.  
    <material name="Gray">
41.  
    <color rgba="0.5 0.5 0.5 1.0"/>
42.  
    </material>
43.  
    </visual>
44.  
    <!-- 碰撞区域 -->
45.  
    <collision>
46.  
    <origin rpy="1.5707963267948966 0 0" xyz="0 0 0"/>
47.  
    <geometry>
48.  
    <cylinder length="0.06" radius="0.0775"/>
49.  
    </geometry>
50.  
    </collision>
51.  
    <inertial>
52.  
    <origin rpy="1.5707963267948966 0 0" xyz="0 0 0"/>
53.  
    <mass value="0.8"/>
54.  
    <inertia ixx="0.0014412499999999998" ixy="0" ixz="0" iyy="0.0014412499999999998" iyz="0" izz="0.0024025"/>
55.  
    </inertial>
56.  
    </link>
57.  
    <!-- 轮子关节 -->
58.  
    <joint name="left_wheel_joint" type="continuous">
59.  
    <parent link="base_link"/>
60.  
    <child link="left_wheel_link"/>
61.  
    <origin rpy="0 0 0" xyz="0.15 0.27 -0.055"/>
62.  
    <axis xyz="0 1 0"/>
63.  
    </joint>
64.  
    <link name="right_wheel_link">
65.  
    <visual>
66.  
    <origin rpy="1.5707963267948966 0 0" xyz="0 0 0"/>
67.  
    <geometry>
68.  
    <cylinder length="0.06" radius="0.0775"/>
69.  
    </geometry>
70.  
    <material name="Gray">
71.  
    <color rgba="0.5 0.5 0.5 1.0"/>
72.  
    </material>
73.  
    </visual>
74.  
    <!-- 碰撞区域 -->
75.  
    <collision>
76.  
    <origin rpy="1.5707963267948966 0 0" xyz="0 0 0"/>
77.  
    <geometry>
78.  
    <cylinder length="0.06" radius="0.0775"/>
79.  
    </geometry>
80.  
    </collision>
81.  
    <inertial>
82.  
    <origin rpy="1.5707963267948966 0 0" xyz="0 0 0"/>
83.  
    <mass value="0.8"/>
84.  
    <inertia ixx="0.0014412499999999998" ixy="0" ixz="0" iyy="0.0014412499999999998" iyz="0" izz="0.0024025"/>
85.  
    </inertial>
86.  
    </link>
87.  
    <!-- 轮子关节 -->
88.  
    <joint name="right_wheel_joint" type="continuous">
89.  
    <parent link="base_link"/>
90.  
    <child link="right_wheel_link"/>
91.  
    <origin rpy="0 0 0" xyz="0.15 -0.27 -0.055"/>
92.  
    <axis xyz="0 1 0"/>
93.  
    </joint>
94.  
    <!-- 支撑轮 -->
95.  
    <link name="caster_link">
96.  
    <visual>
97.  
    <geometry>
98.  
    <sphere radius="0.03875"/>
99.  
    </geometry>
100.  
     <material name="Cyan">
101.  
     <color rgba="0 1.0 1.0 1.0"/>
102.  
     </material>
103.  
     </visual>
104.  
     <!-- 碰撞区域 -->
105.  
     <collision>
106.  
     <origin rpy="0 0 0" xyz="0 0 0"/>
107.  
     <geometry>
108.  
     <sphere radius="0.03875"/>
109.  
     </geometry>
110.  
     </collision>
111.  
     <inertial>
112.  
     <mass value="0.5"/>
113.  
     <inertia ixx="0.0003003125" ixy="0.0" ixz="0.0" iyy="0.0003003125" iyz="0.0" izz="0.0003003125"/>
114.  
     </inertial>
115.  
     </link>
116.  
     <!-- 支撑轮gazebo颜色 -->
117.  
     <gazebo reference="caster_link">
118.  
     <material>Gazebo/Black</material>
119.  
     </gazebo>
120.  
     <!-- 支撑轮gazebo摩擦力 -->
121.  
     <gazebo reference="caster_link">
122.  
     <mu1 value="0.0"/>
123.  
     <mu2 value="0.0"/>
124.  
     <kp value="1000000.0"/>
125.  
     <kd value="10.0"/>
126.  
     </gazebo>
127.  
     <!-- 支撑轮关节 -->
128.  
     <joint name="caster_joint" type="fixed">
129.  
     <parent link="base_link"/>
130.  
     <child link="caster_link"/>
131.  
     <origin rpy="0 0 0" xyz="-0.205 0.0 -0.09375"/>
132.  
     </joint>
133.  
     <!-- imu -->
134.  
     <link name="imu_link">
135.  
     <visual>
136.  
     <geometry>
137.  
     <box size="0.06 0.03 0.03"/>
138.  
     </geometry>
139.  
     </visual>
140.  
     <!-- 碰撞区域 -->
141.  
     <collision>
142.  
     <geometry>
143.  
     <box size="0.06 0.03 0.03"/>
144.  
     </geometry>
145.  
     </collision>
146.  
     <inertial>
147.  
     <origin rpy="1.5707963267948966 0 1.5707963267948966" xyz="0 0 0"/>
148.  
     <mass value="0.1"/>
149.  
     <inertia ixx="0.0001666666666666667" ixy="0.0" ixz="0.0" iyy="0.0001666666666666667" iyz="0.0" izz="0.0001666666666666667"/>
150.  
     </inertial>
151.  
     </link>
152.  
     <!-- imu关节 -->
153.  
     <joint name="imu_joint" type="fixed">
154.  
     <parent link="base_link"/>
155.  
     <child link="imu_link"/>
156.  
     <origin xyz="-0.05 0 -0.055"/>
157.  
     </joint>
158.  
     <!-- imu仿真插件 -->
159.  
     <gazebo reference="imu_link">
160.  
     <sensor name="imu_sensor" type="imu">
161.  
     <plugin filename="libgazebo_ros_imu_sensor.so" name="imu_plugin">
162.  
     <ros>
163.  
     <!-- 命名空间 -->
164.  
     <!-- <namespace>/demo</namespace> -->
165.  
     <remapping>~/out:=imu</remapping>
166.  
     </ros>
167.  
     <!-- 初始方位_参考 -->
168.  
     <initial_orientation_as_reference>false</initial_orientation_as_reference>
169.  
     </plugin>
170.  
     <always_on>true</always_on>
171.  
     <!-- 更新频率 -->
172.  
     <update_rate>100</update_rate>
173.  
     <visualize>true</visualize>
174.  
     <imu>
175.  
     <!-- 角速度 -->
176.  
     <angular_velocity>
177.  
     <x>
178.  
     <noise type="gaussian">
179.  
     <mean>0.0</mean>
180.  
     <stddev>2e-4</stddev>
181.  
     <bias_mean>0.0000075</bias_mean>
182.  
     <bias_stddev>0.0000008</bias_stddev>
183.  
     </noise>
184.  
     </x>
185.  
     <y>
186.  
     <noise type="gaussian">
187.  
     <mean>0.0</mean>
188.  
     <stddev>2e-4</stddev>
189.  
     <bias_mean>0.0000075</bias_mean>
190.  
     <bias_stddev>0.0000008</bias_stddev>
191.  
     </noise>
192.  
     </y>
193.  
     <z>
194.  
     <noise type="gaussian">
195.  
     <mean>0.0</mean>
196.  
     <stddev>2e-4</stddev>
197.  
     <bias_mean>0.0000075</bias_mean>
198.  
     <bias_stddev>0.0000008</bias_stddev>
199.  
     </noise>
200.  
     </z>
201.  
     </angular_velocity>
202.  
     <!-- 线性加速度 -->
203.  
     <linear_acceleration>
204.  
     <x>
205.  
     <noise type="gaussian">
206.  
     <mean>0.0</mean>
207.  
     <stddev>1.7e-2</stddev>
208.  
     <bias_mean>0.1</bias_mean>
209.  
     <bias_stddev>0.001</bias_stddev>
210.  
     </noise>
211.  
     </x>
212.  
     <y>
213.  
     <noise type="gaussian">
214.  
     <mean>0.0</mean>
215.  
     <stddev>1.7e-2</stddev>
216.  
     <bias_mean>0.1</bias_mean>
217.  
     <bias_stddev>0.001</bias_stddev>
218.  
     </noise>
219.  
     </y>
220.  
     <z>
221.  
     <noise type="gaussian">
222.  
     <mean>0.0</mean>
223.  
     <stddev>1.7e-2</stddev>
224.  
     <bias_mean>0.1</bias_mean>
225.  
     <bias_stddev>0.001</bias_stddev>
226.  
     </noise>
227.  
     </z>
228.  
     </linear_acceleration>
229.  
     </imu>
230.  
     </sensor>
231.  
     </gazebo>
232.  
     <!-- 差速驱动仿真插件 -->
233.  
     <gazebo>
234.  
     <plugin filename="libgazebo_ros_diff_drive.so" name="diff_drive">
235.  
     <ros>
236.  
     <!-- 命名空间 -->
237.  
     <!-- <namespace>/demo</namespace> -->
238.  
     </ros>
239.  
     <!-- 左右轮子 -->
240.  
     <left_joint>left_wheel_joint</left_joint>
241.  
     <right_joint>right_wheel_joint</right_joint>
242.  
     <!-- 轮距 轮子直径 -->
243.  
     <wheel_separation>0.52</wheel_separation>
244.  
     <!-- <wheel_separation>0.52</wheel_separation> -->
245.  
     <wheel_diameter>0.155</wheel_diameter>
246.  
     <!-- <wheel_diameter>0.155</wheel_diameter> -->
247.  
     <!-- 最大扭矩 最大加速度 -->
248.  
     <max_wheel_torque>20</max_wheel_torque>
249.  
     <max_wheel_acceleration>1.0</max_wheel_acceleration>
250.  
     <!-- 输出 -->
251.  
     <!-- 是否发布里程计 -->
252.  
     <publish_odom>true</publish_odom>
253.  
     <!-- 是否发布里程计的tf开关 -->
254.  
     <publish_odom_tf>true</publish_odom_tf>
255.  
     <!-- 是否发布轮子的tf数据开关 -->
256.  
     <publish_wheel_tf>true</publish_wheel_tf>
257.  
     <!-- 里程计的framed ID，最终体现在话题和TF上 -->
258.  
     <odometry_frame>odom</odometry_frame>
259.  
     <!-- 机器人的基础frame的ID -->
260.  
     <robot_base_frame>base_link</robot_base_frame>
261.  
     </plugin>
262.  
     </gazebo>
263.  
     <!-- 雷达 -->
264.  
     <link name="laser">
265.  
     <visual>
266.  
     <origin rpy="0 0 0" xyz="0 0 0"/>
267.  
     <geometry>
268.  
     <cylinder length="0.04" radius="0.04"/>
269.  
     </geometry>
270.  
     </visual>
271.  
     <!-- 惯性属性 -->
272.  
     <inertial>
273.  
     <origin rpy="0 0 0" xyz="0 0 0"/>
274.  
     <mass value="0.125"/>
275.  
     <inertia ixx="0.001" ixy="0" ixz="0" iyy="0.001" iyz="0" izz="0.001"/>
276.  
     </inertial>
277.  
     <!-- 碰撞区域 -->
278.  
     <collision>
279.  
     <origin rpy="0 0 0" xyz="0 0 0"/>
280.  
     <geometry>
281.  
     <cylinder length="0.04" radius="0.04"/>
282.  
     </geometry>
283.  
     </collision>
284.  
     </link>
285.  
     <!-- 雷达关节 -->
286.  
     <joint name="laser_joint" type="fixed">
287.  
     <parent link="base_link"/>
288.  
     <child link="laser"/>
289.  
     <origin rpy="0 0 0" xyz="0.16 0 0.078"/>
290.  
     </joint>
291.  
     <gazebo reference="laser">
292.  
     <sensor name="laser" type="ray">
293.  
     <always_on>true</always_on>
294.  
     <visualize>false</visualize>
295.  
     <update_rate>5</update_rate>
296.  
     <ray>
297.  
     <scan>
298.  
     <horizontal>
299.  
     <samples>360</samples>
300.  
     <resolution>1.000000</resolution>
301.  
     <min_angle>0.000000</min_angle>
302.  
     <max_angle>6.280000</max_angle>
303.  
     </horizontal>
304.  
     </scan>
305.  
     <range>
306.  
     <min>0.120000</min>
307.  
     <max>3.5</max>
308.  
     <resolution>0.015000</resolution>
309.  
     </range>
310.  
     <noise>
311.  
     <type>gaussian</type>
312.  
     <mean>0.0</mean>
313.  
     <stddev>0.01</stddev>
314.  
     </noise>
315.  
     </ray>
316.  
     <plugin filename="libgazebo_ros_ray_sensor.so" name="scan">
317.  
     <ros>
318.  
     <remapping>~/out:=scan</remapping>
319.  
     </ros>
320.  
     <output_type>sensor_msgs/LaserScan</output_type>
321.  
     <frame_name>laser</frame_name>
322.  
     </plugin>
323.  
     </sensor>
324.  
     </gazebo>
325.  
     <!-- 相机 -->
326.  
     <link name="camera_link">
327.  
     <visual>
328.  
     <origin rpy="0 0 0" xyz="0 0 0"/>
329.  
     <geometry>
330.  
     <box size="0.015 0.130 0.022"/>
331.  
     </geometry>
332.  
     </visual>
333.  
     <!-- 碰撞区域 -->
334.  
     <collision>
335.  
     <origin rpy="0 0 0" xyz="0 0 0"/>
336.  
     <geometry>
337.  
     <box size="0.015 0.130 0.022"/>
338.  
     </geometry>
339.  
     </collision>
340.  
     <!-- 惯性属性 -->
341.  
     <inertial>
342.  
     <origin rpy="0 0 0" xyz="0 0 0"/>
343.  
     <mass value="0.035"/>
344.  
     <inertia ixx="0.001" ixy="0" ixz="0" iyy="0.001" iyz="0" izz="0.001"/>
345.  
     </inertial>
346.  
     </link>
347.  
     <!-- 相机关节 -->
348.  
     <joint name="camera_joint" type="fixed">
349.  
     <parent link="base_link"/>
350.  
     <child link="camera_link"/>
351.  
     <origin rpy="0 0 0" xyz="0.16 0 0.11"/>
352.  
     </joint>
353.  
     <!-- 深度相机 -->
354.  
     <link name="camera_depth_frame"/>
355.  
     <joint name="camera_depth_joint" type="fixed">
356.  
     <origin rpy="0 0 0" xyz="0 0 0"/>
357.  
     <parent link="camera_link"/>
358.  
     <child link="camera_depth_frame"/>
359.  
     </joint>
360.  
     <!-- 相机仿真 -->
361.  
     <gazebo reference="camera_depth_link">
362.  
     <sensor name="depth_camera" type="depth">
363.  
     <visualize>true</visualize>
364.  
     <update_rate>30.0</update_rate>
365.  
     <camera name="camera">
366.  
     <horizontal_fov>1.047198</horizontal_fov>
367.  
     <image>
368.  
     <width>640</width>
369.  
     <height>480</height>
370.  
     <format>R8G8B8</format>
371.  
     </image>
372.  
     <clip>
373.  
     <near>0.05</near>
374.  
     <far>3</far>
375.  
     </clip>
376.  
     </camera>
377.  
     <plugin filename="libgazebo_ros_camera.so" name="depth_camera_controller">
378.  
     <baseline>0.2</baseline>
379.  
     <alwaysOn>true</alwaysOn>
380.  
     <updateRate>0.0</updateRate>
381.  
     <frame_name>camera_depth_frame</frame_name>
382.  
     <pointCloudCutoff>0.5</pointCloudCutoff>
383.  
     <pointCloudCutoffMax>3.0</pointCloudCutoffMax>
384.  
     <distortionK1>0</distortionK1>
385.  
     <distortionK2>0</distortionK2>
386.  
     <distortionK3>0</distortionK3>
387.  
     <distortionT1>0</distortionT1>
388.  
     <distortionT2>0</distortionT2>
389.  
     <CxPrime>0</CxPrime>
390.  
     <Cx>0</Cx>
391.  
     <Cy>0</Cy>
392.  
     <focalLength>0</focalLength>
393.  
     <hackBaseline>0</hackBaseline>
394.  
     </plugin>
395.  
     </sensor>
396.  
     </gazebo>
397.  
     </robot>

xacro编写的小车模型文件：

1.  
   <!-- base.urdf.xacro -->
2.  
   <?xml version="1.0"?>
3.  
   <robot name="jtbot"
4.  
   xmlns:xacro="http://ros.org/wiki/xacro">
5.  
    
6.  
   <!-- 定义机器人常量 -->
7.  
   <!-- 底盘 长 宽 高 -->
8.  
   <xacro:property name="base_width" value="0.46"/>
9.  
   <xacro:property name="base_length" value="0.46"/>
10.  
    <xacro:property name="base_height" value="0.11"/>
11.  
    <!-- 轮子半径 -->
12.  
    <xacro:property name="wheel_radius" value="0.0775"/>
13.  
    <!-- 轮子宽度 -->
14.  
    <xacro:property name="wheel_width" value="0.06"/>
15.  
    <!-- 轮子和底盘的间距 -->
16.  
    <xacro:property name="wheel_ygap" value="0.01"/>
17.  
    <!-- 轮子z轴偏移量 -->
18.  
    <xacro:property name="wheel_zoff" value="0.055"/>
19.  
    <!-- 轮子x轴偏移量 -->
20.  
    <xacro:property name="wheel_xoff" value="0.15"/>
21.  
    <!-- 支撑轮x轴偏移量 -->
22.  
    <xacro:property name="caster_xoff" value="0.205"/>
23.  
     
24.  
    <!-- 定义长方形惯性属性宏 -->
25.  
    <xacro:macro name="box_inertia" params="m w h d">
26.  
    <inertial>
27.  
    <origin xyz="0 0 0" rpy="${pi/2} 0 ${pi/2}"/>
28.  
    <mass value="${m}"/>
29.  
    <inertia ixx="${(m/12) * (h*h d*d)}" ixy="0.0" ixz="0.0" iyy="${(m/12) * (w*w d*d)}" iyz="0.0" izz="${(m/12) * (w*w h*h)}"/>
30.  
    </inertial>
31.  
    </xacro:macro>
32.  
    <!-- 定义圆柱惯性属性宏 -->
33.  
    <xacro:macro name="cylinder_inertia" params="m r h">
34.  
    <inertial>
35.  
    <origin xyz="0 0 0" rpy="${pi/2} 0 0" />
36.  
    <mass value="${m}"/>
37.  
    <inertia ixx="${(m/12) * (3*r*r h*h)}" ixy = "0" ixz = "0" iyy="${(m/12) * (3*r*r h*h)}" iyz = "0" izz="${(m/2) * (r*r)}"/>
38.  
    </inertial>
39.  
    </xacro:macro>
40.  
    <!-- 定义球体惯性属性宏 -->
41.  
    <xacro:macro name="sphere_inertia" params="m r">
42.  
    <inertial>
43.  
    <mass value="${m}"/>
44.  
    <inertia ixx="${(2/5) * m * (r*r)}" ixy="0.0" ixz="0.0" iyy="${(2/5) * m * (r*r)}" iyz="0.0" izz="${(2/5) * m * (r*r)}"/>
45.  
    </inertial>
46.  
    </xacro:macro>
47.  
     
48.  
    <!-- 机器人底盘 -->
49.  
    <link name="base_link">
50.  
    <visual>
51.  
    <geometry>
52.  
    <box size="${base_length} ${base_width} ${base_height}"/>
53.  
    </geometry>
54.  
    <material name="Cyan">
55.  
    <color rgba="0 1.0 1.0 1.0"/>
56.  
    </material>
57.  
    </visual>
58.  
    <!-- 碰撞区域 -->
59.  
    <collision>
60.  
    <geometry>
61.  
    <box size="${base_length} ${base_width} ${base_height}"/>
62.  
    </geometry>
63.  
    </collision>
64.  
    <!-- 惯性特性 -->
65.  
    <xacro:box_inertia m="15" w="${base_width}" d="${base_length}" h="${base_height}"/>
66.  
    </link>
67.  
     
68.  
    <!-- 机器人 Footprint -->
69.  
    <link name="base_footprint"/>
70.  
    <!-- 底盘关节 -->
71.  
    <joint name="base_joint" type="fixed">
72.  
    <parent link="base_link"/>
73.  
    <child link="base_footprint"/>
74.  
    <origin xyz="0.0 0.0 ${-(wheel_radius wheel_zoff)}" rpy="0 0 0"/>
75.  
    </joint>
76.  
     
77.  
    <!-- 创建轮子宏函数 -->
78.  
    <xacro:macro name="wheel" params="prefix x_reflect y_reflect">
79.  
    <link name="${prefix}_link">
80.  
    <visual>
81.  
    <origin xyz="0 0 0" rpy="${pi/2} 0 0"/>
82.  
    <geometry>
83.  
    <cylinder radius="${wheel_radius}" length="${wheel_width}"/>
84.  
    </geometry>
85.  
    <material name="Gray">
86.  
    <color rgba="0.5 0.5 0.5 1.0"/>
87.  
    </material>
88.  
    </visual>
89.  
    <!-- 碰撞区域 -->
90.  
    <collision>
91.  
    <origin xyz="0 0 0" rpy="${pi/2} 0 0"/>
92.  
    <geometry>
93.  
    <cylinder radius="${wheel_radius}" length="${wheel_width}"/>
94.  
    </geometry>
95.  
    </collision>
96.  
    <!-- 惯性属性 -->
97.  
    <xacro:cylinder_inertia m="0.8" r="${wheel_radius}" h="${wheel_width}"/>
98.  
    </link>
99.  
    <!-- 轮子关节 -->
100.  
     <joint name="${prefix}_joint" type="continuous">
101.  
     <parent link="base_link"/>
102.  
     <child link="${prefix}_link"/>
103.  
     <origin xyz="${x_reflect*wheel_xoff} ${y_reflect*(base_width/2 wheel_width/2 wheel_ygap)} ${-wheel_zoff}" rpy="0 0 0"/>
104.  
     <axis xyz="0 1 0"/>
105.  
     </joint>
106.  
     </xacro:macro>
107.  
     <!-- 根据上面的宏函数实例化左右轮 -->
108.  
     <xacro:wheel prefix="left_wheel" x_reflect="1" y_reflect="1" />
109.  
     <xacro:wheel prefix="right_wheel" x_reflect="1" y_reflect="-1" />
110.  
      
111.  
     <!-- 支撑轮 -->
112.  
     <link name="caster_link">
113.  
     <visual>
114.  
     <geometry>
115.  
     <sphere radius="${(wheel_radius/2)}"/>
116.  
     </geometry>
117.  
     <material name="Cyan">
118.  
     <color rgba="0 1.0 1.0 1.0"/>
119.  
     </material>
120.  
     </visual>
121.  
     <!-- 碰撞区域 -->
122.  
     <collision>
123.  
     <origin xyz="0 0 0" rpy="0 0 0"/>
124.  
     <geometry>
125.  
     <sphere radius="${(wheel_radius/2)}"/>
126.  
     </geometry>
127.  
     </collision>
128.  
     <!-- 惯性属性 -->
129.  
     <xacro:sphere_inertia m="0.5" r="${(wheel_radius/2)}"/>
130.  
     </link>
131.  
     <!-- 支撑轮gazebo颜色 -->
132.  
     <gazebo reference="caster_link">
133.  
     <material>Gazebo/Black</material>
134.  
     </gazebo>
135.  
     <!-- 支撑轮gazebo摩擦力 -->
136.  
     <gazebo reference="caster_link">
137.  
     <mu1 value="0.0"/>
138.  
     <mu2 value="0.0"/>
139.  
     <kp value="1000000.0" />
140.  
     <kd value="10.0" />
141.  
     </gazebo>
142.  
     <!-- 支撑轮关节 -->
143.  
     <joint name="caster_joint" type="fixed">
144.  
     <parent link="base_link"/>
145.  
     <child link="caster_link"/>
146.  
     <origin xyz="${-caster_xoff} 0.0 ${-(base_height wheel_radius)/2}" rpy="0 0 0"/>
147.  
     </joint>
148.  
     <!-- imu -->
149.  
     <link name="imu_link">
150.  
     <visual>
151.  
     <geometry>
152.  
     <box size="0.06 0.03 0.03"/>
153.  
     </geometry>
154.  
     </visual>
155.  
     <!-- 碰撞区域 -->
156.  
     <collision>
157.  
     <geometry>
158.  
     <box size="0.06 0.03 0.03"/>
159.  
     </geometry>
160.  
     </collision>
161.  
     <!-- 惯性属性 -->
162.  
     <xacro:box_inertia m="0.1" w="0.1" d="0.1" h="0.1"/>
163.  
     </link>
164.  
     <!-- imu关节 -->
165.  
     <joint name="imu_joint" type="fixed">
166.  
     <parent link="base_link"/>
167.  
     <child link="imu_link"/>
168.  
     <origin xyz="-0.05 0 -0.055"/>
169.  
     </joint>
170.  
     <!-- imu仿真插件 -->
171.  
     <gazebo reference="imu_link">
172.  
     <sensor name="imu_sensor" type="imu">
173.  
     <plugin filename="libgazebo_ros_imu_sensor.so" name="imu_plugin">
174.  
     <ros>
175.  
     <!-- 命名空间 -->
176.  
     <!-- <namespace>/demo</namespace> -->
177.  
     <remapping>~/out:=imu</remapping>
178.  
     </ros>
179.  
     <!-- 初始方位_参考 -->
180.  
     <initial_orientation_as_reference>true</initial_orientation_as_reference>
181.  
     </plugin>
182.  
     <always_on>true</always_on>
183.  
     <!-- 更新频率 -->
184.  
     <update_rate>100</update_rate>
185.  
     <visualize>true</visualize>
186.  
     <imu>
187.  
     <!-- 角速度 -->
188.  
     <angular_velocity>
189.  
     <x>
190.  
     <noise type="gaussian">
191.  
     <mean>0.0</mean>
192.  
     <stddev>2e-4</stddev>
193.  
     <bias_mean>0.0000075</bias_mean>
194.  
     <bias_stddev>0.0000008</bias_stddev>
195.  
     </noise>
196.  
     </x>
197.  
     <y>
198.  
     <noise type="gaussian">
199.  
     <mean>0.0</mean>
200.  
     <stddev>2e-4</stddev>
201.  
     <bias_mean>0.0000075</bias_mean>
202.  
     <bias_stddev>0.0000008</bias_stddev>
203.  
     </noise>
204.  
     </y>
205.  
     <z>
206.  
     <noise type="gaussian">
207.  
     <mean>0.0</mean>
208.  
     <stddev>2e-4</stddev>
209.  
     <bias_mean>0.0000075</bias_mean>
210.  
     <bias_stddev>0.0000008</bias_stddev>
211.  
     </noise>
212.  
     </z>
213.  
     </angular_velocity>
214.  
     <!-- 线性加速度 -->
215.  
     <linear_acceleration>
216.  
     <x>
217.  
     <noise type="gaussian">
218.  
     <mean>0.0</mean>
219.  
     <stddev>1.7e-2</stddev>
220.  
     <bias_mean>0.1</bias_mean>
221.  
     <bias_stddev>0.001</bias_stddev>
222.  
     </noise>
223.  
     </x>
224.  
     <y>
225.  
     <noise type="gaussian">
226.  
     <mean>0.0</mean>
227.  
     <stddev>1.7e-2</stddev>
228.  
     <bias_mean>0.1</bias_mean>
229.  
     <bias_stddev>0.001</bias_stddev>
230.  
     </noise>
231.  
     </y>
232.  
     <z>
233.  
     <noise type="gaussian">
234.  
     <mean>0.0</mean>
235.  
     <stddev>1.7e-2</stddev>
236.  
     <bias_mean>0.1</bias_mean>
237.  
     <bias_stddev>0.001</bias_stddev>
238.  
     </noise>
239.  
     </z>
240.  
     </linear_acceleration>
241.  
     </imu>
242.  
     </sensor>
243.  
     </gazebo>
244.  
     <!-- 差速驱动仿真插件 -->
245.  
     <gazebo>
246.  
     <plugin name='diff_drive' filename='libgazebo_ros_diff_drive.so'>
247.  
     <ros>
248.  
     <!-- 命名空间 -->
249.  
     <!-- <namespace>/demo</namespace> -->
250.  
     </ros>
251.  
      
252.  
     <!-- 左右轮子 -->
253.  
     <left_joint>left_wheel_joint</left_joint>
254.  
     <right_joint>right_wheel_joint</right_joint>
255.  
      
256.  
     <!-- 轮距 轮子直径 -->
257.  
     <wheel_separation>${base_width wheel_width}</wheel_separation>
258.  
     <!-- <wheel_separation>0.52</wheel_separation> -->
259.  
     <wheel_diameter>${wheel_radius*2}</wheel_diameter>
260.  
     <!-- <wheel_diameter>0.155</wheel_diameter> -->
261.  
      
262.  
     <!-- 最大扭矩 最大加速度 -->
263.  
     <max_wheel_torque>20</max_wheel_torque>
264.  
     <max_wheel_acceleration>1.0</max_wheel_acceleration>
265.  
      
266.  
     <!-- 输出 -->
267.  
     <!-- 是否发布里程计 -->
268.  
     <publish_odom>true</publish_odom>
269.  
     <!-- 是否发布里程计的tf开关 -->
270.  
     <publish_odom_tf>true</publish_odom_tf>
271.  
     <!-- 是否发布轮子的tf数据开关 -->
272.  
     <publish_wheel_tf>true</publish_wheel_tf>
273.  
      
274.  
     <!-- 里程计的framed ID，最终体现在话题和TF上 -->
275.  
     <odometry_frame>odom</odometry_frame>
276.  
     <!-- 机器人的基础frame的ID -->
277.  
     <robot_base_frame>base_link</robot_base_frame>
278.  
     </plugin>
279.  
     </gazebo>
280.  
     <!-- 雷达 -->
281.  
     <link name="laser">
282.  
     <visual>
283.  
     <origin xyz="0 0 0" rpy="0 0 0"/>
284.  
     <geometry>
285.  
     <cylinder radius="0.04" length="0.04"/>
286.  
     </geometry>
287.  
     </visual>
288.  
     <!-- 惯性属性 -->
289.  
     <inertial>
290.  
     <origin xyz="0 0 0" rpy="0 0 0"/>
291.  
     <mass value="0.125"/>
292.  
     <inertia ixx="0.001" ixy="0" ixz="0" iyy="0.001" iyz="0" izz="0.001" />
293.  
     </inertial>
294.  
     <!-- 碰撞区域 -->
295.  
     <collision>
296.  
     <origin xyz="0 0 0" rpy="0 0 0"/>
297.  
     <geometry>
298.  
     <cylinder radius="0.04" length="0.04"/>
299.  
     </geometry>
300.  
     </collision>
301.  
     </link>
302.  
     <!-- 雷达关节 -->
303.  
     <joint name="laser_joint" type="fixed">
304.  
     <parent link="base_link"/>
305.  
     <child link="laser"/>
306.  
     <origin xyz="0.16 0 0.078" rpy="0 0 0"/>
307.  
     </joint>
308.  
      
309.  
     <gazebo reference="laser">
310.  
     <sensor name="laser" type="ray">
311.  
     <always_on>true</always_on>
312.  
     <visualize>false</visualize>
313.  
     <update_rate>5</update_rate>
314.  
     <ray>
315.  
     <scan>
316.  
     <horizontal>
317.  
     <samples>360</samples>
318.  
     <resolution>1.000000</resolution>
319.  
     <min_angle>0.000000</min_angle>
320.  
     <max_angle>6.280000</max_angle>
321.  
     </horizontal>
322.  
     </scan>
323.  
     <range>
324.  
     <min>0.120000</min>
325.  
     <max>3.5</max>
326.  
     <resolution>0.015000</resolution>
327.  
     </range>
328.  
     <noise>
329.  
     <type>gaussian</type>
330.  
     <mean>0.0</mean>
331.  
     <stddev>0.01</stddev>
332.  
     </noise>
333.  
     </ray>
334.  
     <plugin name="scan" filename="libgazebo_ros_ray_sensor.so">
335.  
     <ros>
336.  
     <remapping>~/out:=scan</remapping>
337.  
     </ros>
338.  
     <output_type>sensor_msgs/LaserScan</output_type>
339.  
     <frame_name>laser</frame_name>
340.  
     </plugin>
341.  
     </sensor>
342.  
     </gazebo>
343.  
     <!-- 相机 -->
344.  
     <link name="camera_link">
345.  
     <visual>
346.  
     <origin xyz="0 0 0" rpy="0 0 0"/>
347.  
     <geometry>
348.  
     <box size="0.015 0.130 0.022"/>
349.  
     </geometry>
350.  
     </visual>
351.  
     <!-- 碰撞区域 -->
352.  
     <collision>
353.  
     <origin xyz="0 0 0" rpy="0 0 0"/>
354.  
     <geometry>
355.  
     <box size="0.015 0.130 0.022"/>
356.  
     </geometry>
357.  
     </collision>
358.  
     <!-- 惯性属性 -->
359.  
     <inertial>
360.  
     <origin xyz="0 0 0" rpy="0 0 0"/>
361.  
     <mass value="0.035"/>
362.  
     <inertia ixx="0.001" ixy="0" ixz="0" iyy="0.001" iyz="0" izz="0.001" />
363.  
     </inertial>
364.  
     </link>
365.  
     <!-- 相机关节 -->
366.  
     <joint name="camera_joint" type="fixed">
367.  
     <parent link="base_link"/>
368.  
     <child link="camera_link"/>
369.  
     <origin xyz="0.16 0 0.11" rpy="0 0 0"/>
370.  
     </joint>
371.  
     <!-- 深度相机 -->
372.  
     <link name="camera_depth_frame"/>
373.  
      
374.  
     <joint name="camera_depth_joint" type="fixed">
375.  
     <origin xyz="0 0 0" rpy="0 0 0"/>
376.  
     <parent link="camera_link"/>
377.  
     <child link="camera_depth_frame"/>
378.  
     </joint>
379.  
     <!-- 相机仿真 -->
380.  
     <gazebo reference="camera_depth_link">
381.  
     <sensor name="depth_camera" type="depth">
382.  
     <visualize>true</visualize>
383.  
     <update_rate>30.0</update_rate>
384.  
     <camera name="camera">
385.  
     <horizontal_fov>1.047198</horizontal_fov>
386.  
     <image>
387.  
     <width>640</width>
388.  
     <height>480</height>
389.  
     <format>R8G8B8</format>
390.  
     </image>
391.  
     <clip>
392.  
     <near>0.05</near>
393.  
     <far>3</far>
394.  
     </clip>
395.  
     </camera>
396.  
     <plugin name="depth_camera_controller" filename="libgazebo_ros_camera.so">
397.  
     <baseline>0.2</baseline>
398.  
     <alwaysOn>true</alwaysOn>
399.  
     <updateRate>0.0</updateRate>
400.  
     <frame_name>camera_depth_frame</frame_name>
401.  
     <pointCloudCutoff>0.5</pointCloudCutoff>
402.  
     <pointCloudCutoffMax>3.0</pointCloudCutoffMax>
403.  
     <distortionK1>0</distortionK1>
404.  
     <distortionK2>0</distortionK2>
405.  
     <distortionK3>0</distortionK3>
406.  
     <distortionT1>0</distortionT1>
407.  
     <distortionT2>0</distortionT2>
408.  
     <CxPrime>0</CxPrime>
409.  
     <Cx>0</Cx>
410.  
     <Cy>0</Cy>
411.  
     <focalLength>0</focalLength>
412.  
     <hackBaseline>0</hackBaseline>
413.  
     </plugin>
414.  
     </sensor>
415.  
     </gazebo>
416.  
      
417.  
     </robot>

xacro模型文件需要转成urdf模型文件才能使用

方法1 提前转换：

当前文件夹打开终端输入：base.urdf.xacro > base.urdf生成纯urdf文件。

方法2 在运行launch文件的时候自动转，需要加入xacro解析步骤

package.xml文件内在<test_depend>前加入：<exec_depend>xacro</exec_depend>

launch文件编写：

1.  
   # 此launch文件是机器人仿真程序，包含 gazebo启动，机器人仿真生成，机器人模型状态发布
2.  
   import os
3.  
   from launch import LaunchDescription
4.  
   from launch.actions import ExecuteProcess
5.  
   from launch_ros.actions import Node
6.  
   from launch_ros.substitutions import FindPackageShare
7.  
   from launch.substitutions import LaunchConfiguration
8.  
   import xacro
9.  
    
10.  
    def generate_launch_description():
11.  
    robot_name_in_model = 'jtbot' #机器人模型名字
12.  
    package_name = 'jtbot_description' #模型包名
13.  
     
14.  
    ld = LaunchDescription()
15.  
    use_sim_time = LaunchConfiguration('use_sim_time', default='true')
16.  
    pkg_share = FindPackageShare(package=package_name).find(package_name)
17.  
    gazebo_world_path = os.path.join(pkg_share, 'world/jt.world') #世界仿真文件路径
18.  
    default_rviz_config_path = os.path.join(pkg_share, 'rviz/mrviz2.rviz') #rviz配置文件路径
19.  
    urdf_xacro_file = os.path.join(pkg_share, 'urdf/jtbot_base.urdf.xacro') #xacro模型文件路径
20.  
    #解析xacro模型文件
21.  
    doc = xacro.parse(open(urdf_xacro_file))
22.  
    xacro.process_doc(doc)
23.  
    params = {'robot_description': doc.toxml()}
24.  
     
25.  
    # 开启ros Gazebo server
26.  
    start_gazebo_cmd = ExecuteProcess(
27.  
    cmd=['gazebo',
28.  
    '--verbose',
29.  
    gazebo_world_path,
30.  
    '-s', 'libgazebo_ros_init.so',
31.  
    '-s', 'libgazebo_ros_factory.so',
32.  
     
33.  
    ],
34.  
    output='screen')
35.  
     
36.  
    # Start Robot State publisher
37.  
    start_robot_state_publisher_cmd = Node(
38.  
    package='robot_state_publisher',
39.  
    executable='robot_state_publisher',
40.  
    output='screen',
41.  
     
42.  
    parameters=[params,{'use_sim_time': use_sim_time}]
43.  
    )
44.  
     
45.  
    # gazebo内生成机器人
46.  
    spawn_entity_cmd = Node(
47.  
    package='gazebo_ros',
48.  
    executable='spawn_entity.py',
49.  
    arguments=['-entity', robot_name_in_model, '-topic', 'robot_description'],
50.  
    output='screen'
51.  
     
52.  
    )
53.  
     
54.  
     
55.  
     
56.  
    # Launch RViz
57.  
    start_rviz_cmd = Node(
58.  
    package='rviz2',
59.  
    executable='rviz2',
60.  
    name='rviz2',
61.  
    output='screen',
62.  
    arguments=['-d', default_rviz_config_path]
63.  
    )
64.  
     
65.  
    ld.add_action(start_gazebo_cmd)
66.  
    ld.add_action(spawn_entity_cmd)
67.  
    ld.add_action(start_robot_state_publisher_cmd)
68.  
    ld.add_action(start_rviz_cmd)
69.  
     
70.  
     
71.  
    return ld

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