八 Gazebo学习总结之附加抓手到机器人

开始Gazebo，确定能从先前的教程中载入模型。

1.应该有如下图所示的底座。

2.根据经验，为了使模型变大，修改~/.gazebo/models/my_robot/model.sdf，让小车能容纳抓手。

gedit ~/.gazebo/models/my_robot/model.sdf

按以下程序更新内容：

<?xml version='1.0'?>
<sdf version='1.4'>
<model name="mobile_base">
<link name='chassis'>
  <pose>0 0 .25 0 0 0</pose>

  <inertial>
    <mass>20.0</mass>
    <pose>-0.1 0 -0.1 0 0 0</pose>
    <inertia>
      <ixx>0.5</ixx>
      <iyy>1.0</iyy>
      <izz>0.1</izz>
    </inertia>
  </inertial>

  <collision name='collision'>
    <geometry>
      <box>
        <size>2 1 0.3</size>
      </box>
    </geometry>
  </collision>

  <visual name='visual'>
    <geometry>
      <box>
        <size>2 1 0.3</size>
      </box>
    </geometry>
  </visual>

  <collision name='caster_collision'>
    <pose>-0.8 0 -0.125 0 0 0</pose>
    <geometry>
      <sphere>
        <radius>.125</radius>
      </sphere>
    </geometry>

    <surface>
      <friction>
        <ode>
          <mu>0</mu>
          <mu2>0</mu2>
        </ode>
      </friction>
    </surface>
  </collision>

  <visual name='caster_visual'>
    <pose>-0.8 0 -0.125 0 0 0</pose>
    <geometry>
      <sphere>
        <radius>.125</radius>
      </sphere>
    </geometry>
  </visual>
</link>
<link name="left_wheel">
  <pose>0.8 0.6 0.125 0 1.5707 1.5707</pose>
  <collision name="collision">
    <geometry>
      <cylinder>
        <radius>.125</radius>
        <length>.05</length>
      </cylinder>
    </geometry>
  </collision>
  <visual name="visual">
    <geometry>
      <cylinder>
        <radius>.125</radius>
        <length>.05</length>
      </cylinder>
    </geometry>
  </visual>
</link>

<link name="right_wheel">
  <pose>0.8 -0.6 0.125 0 1.5707 1.5707</pose>
  <collision name="collision">
    <geometry>
      <cylinder>
        <radius>.125</radius>
        <length>.05</length>
      </cylinder>
    </geometry>
  </collision>
  <visual name="visual">
    <geometry>
      <cylinder>
        <radius>.125</radius>
        <length>.05</length>
      </cylinder>
    </geometry>
  </visual>
</link>

<joint type="revolute" name="left_wheel_hinge">
  <pose>0 0 -0.03 0 0 0</pose>
  <child>left_wheel</child>
  <parent>chassis</parent>
  <axis>
    <xyz>0 1 0</xyz>
  </axis>
</joint>

<joint type="revolute" name="right_wheel_hinge">
  <pose>0 0 0.03 0 0 0</pose>
  <child>right_wheel</child>
  <parent>chassis</parent>
  <axis>
    <xyz>0 1 0</xyz>
  </axis>
</joint>

</model>
</sdf>

更新后结果如下：

组装复合机器人：

1.创建新的模型目录

mkdir ~/.gazebo/models/simple_mobile_manipulator
cd ~/.gazebo/models/simple_mobile_manipulator

编辑模型的配置文件

gedit ~/.gazebo/models/simple_mobile_manipulator/model.config

复制以下程序到配置文件：

<?xml version="1.0"?>
<model>
<name>Simple Mobile Manipulator</name>
<version>1.0</version>
<sdf version='1.4'>model.sdf</sdf>

<author>
<name>My Name</name>
<email>[e-mail]</email>
</author>

<description>
My simple mobile manipulator
</description>
</model>

2.创建模型SDF文件。

gedit ~/.gazebo/models/simple_mobile_manipulator/model.sdf

复制以下内容到.sdf文件中：

<?xml version="1.0" ?>
<sdf version="1.3">
<model name="simple_mobile_manipulator">

<include>
  <uri>model://my_gripper</uri>
  <pose>1.3 0 0.1 0 0 0</pose>
</include>

<include>
  <uri>model://my_robot</uri>
  <pose>0 0 0 0 0 0</pose>
</include>

<joint name="arm_gripper_joint" type="revolute">
  <parent>mobile_base::chassis</parent>
  <child>simple_gripper::riser</child>
  <axis>
    <limit>
      <lower>0</lower>
      <upper>0</upper>
    </limit>
    <xyz>0 0 1</xyz>
  </axis>
</joint>

<!-- attach sensor to the gripper -->
<include>
  <uri>model://hokuyo</uri>
  <pose>1.3 0 0.3 0 0 0</pose>
</include>

<joint name="hokuyo_joint" type="revolute">
  <child>hokuyo::link</child>
  <parent>simple_gripper::palm</parent>
  <axis>
    <xyz>0 0 1</xyz>
    <limit>
      <upper>0</upper>
      <lower>0</lower>
    </limit>
  </axis>
</joint>

</model>
</sdf>

3.保存模型的.config和.sdf文件，运行Gazebo。

本文靠自己理解，翻译而来，错误之处望不吝指教！！！