1 자유도 로봇 모델 제작
목적
실제 웨어러블 로봇의 제작을 앞서 가제보와 ROS의 기능 테스트를 위한 간단 버전 로봇 모델 제작
개발 환경
URDF 뷰어: vscode에서 ros_extension을 설치하여 URDF 결과물을 미리 보면서 편집
ROS 2 개발환경: Ubuntu 20.04, ROS 2 Foxy, Gazebo 11
Gazebo에서 로봇 모델 작성하는 순서
1. URDF 작성.
2. robot state publisher 노드 를 이용하여 robot_description 노드에 로봇의 URDF 보내기.
3. gazebo에 URDF로 정의된 로봇 올리기: spawn_entity.py
4 joint state publisher와 joint state broadcaster 노드 를 이용하여 joint 상태를 토픽으로 출판.
5. joint trajetory controller 노드 를 이용하여 robot의 joint를 ROS action으로 제어하도록 인터페이스 연결
구현
https://github.com/donghee/wearable_robot_eval
colcon build && source ./install/setup.bash && ros2 launch wearable_robot_gazebo 1_dof_arm.launch.py
1 자유도 로봇
1 자유도 로봇 모델
URDF 파일
<?xml version="1.0"?>
<robot name="1_dof_arm" xmlns:xacro="http://www.ros.org/wiki/xacro">
<!-- Import all Gazebo-customization elements, including Gazebo colors -->
<xacro:include filename="$(find wearable_robot_description)/urdf/1_dof_arm.gazebo"/>
<!-- Import Rviz colors -->
<xacro:include filename="$(find wearable_robot_description)/urdf/materials.xacro"/>
<link name="world"/>
<joint name="fixed" type="fixed">
<parent link="world"/>
<child link="arm_link"/>
</joint>
<link name="arm_link">
<visual>
<geometry>
<cylinder length="0.3" radius="0.01"/>
</geometry>
<origin rpy="0 0 1.570796" xyz="0.72 1 1.275"/>
<material name="blue">
<color rgba="0 0 1 1"/>
</material>
</visual>
<collision>
<geometry>
<cylinder length="0.3" radius="0.01"/>
</geometry>
<origin rpy="0 0 1.570796" xyz="0.72 1 1.275"/>
</collision>
<inertial>
<mass value="0.5"/>
<inertia ixx="1.0" ixy="0.0" ixz="0.0" iyy="1.0" iyz="0.0" izz="1.0"/>
</inertial>
</link>
<joint name="arm_joint" type="revolute">
<parent link="arm_link"/>
<child link="forearm_link"/>
<origin xyz="0.72 1 1.125"/>
<axis xyz="0 0 0" />
<!-- <limit effort="300" velocity="0.1" lower="4.71" upper="1.8"/> -->
<limit effort="300" velocity="0.1" lower="-4.1" upper="-1.5"/>
<dynamics damping="50" friction="1"/>
</joint>
<link name="forearm_link">
<visual>
<geometry>
<cylinder length="0.25" radius="0.01"/>
</geometry>
<origin rpy="1.570796 0 0" xyz="0 0.125 0"/>
<material name="red">
<color rgba="1 0 0 1"/>
</material>
</visual>
<collision>
<geometry>
<cylinder length="0.25" radius="0.01"/>
</geometry>
<origin rpy="1.570796 0 0" xyz="0 0.125 0"/>
</collision>
<inertial>
<mass value="0.5"/>
<inertia ixx="1.0" ixy="0.0" ixz="0.0" iyy="1.0" iyz="0.0" izz="1.0"/>
</inertial>
</link>
<joint name="forearm_band_link_fix_to_forearm_link" type="fixed">
<origin xyz="0.12 0.18 0.05" rpy="0 1.570796 0"/>
<parent link="forearm_link"/>
<child link="forearm_band_link"/>
</joint>
<link name="forearm_band_link">
<visual>
<geometry>
<cylinder length="0.01" radius="0.005"/>
</geometry>
<origin rpy="0 0 0" xyz="0 0 0"/>
<material name="red">
<color rgba="1 0 0 1"/>
</material>
</visual>
<visual>
<geometry>
<cylinder length="0.01" radius="0.005"/>
</geometry>
<origin rpy="0 0 0" xyz="0.1 0 0"/>
<material name="red">
<color rgba="1 0 0 1"/>
</material>
</visual>
<collision>
<geometry>
<cylinder length="0.05" radius="0.02"/>
</geometry>
<origin rpy="0 0 0" xyz="0 0 0"/>
<contact_coefficients mu="2.0" kp="2.0" kd="2.0" />
</collision>
<collision>
<geometry>
<cylinder length="0.05" radius="0.02"/>
</geometry>
<origin rpy="0 0 0" xyz="0.1 0 0"/>
<contact_coefficients mu="2.0" kp="2.0" kd="2.0" />
</collision>
<inertial>
<mass value="0.1"/>
<inertia ixx="1e-2" iyy="1e-2" izz="1e-2" ixy="0" ixz="0" iyz="0"/>
</inertial>
</link>
<joint name="arm_band_link_fix_to_arm_link" type="fixed">
<!-- <origin xyz="0.12 0.19 0.05" rpy="0 1.570796 0"/> -->
<origin xyz="0.85 0.95 1.25" rpy="0 0 1.570796"/>
<axis xyz="0 0 0" />
<parent link="arm_link"/>
<child link="arm_band_link"/>
</joint>
<link name="arm_band_link">
<visual>
<geometry>
<cylinder length="0.01" radius="0.005"/>
</geometry>
<origin rpy="0 0 0" xyz="0.0 0 0"/>
<material name="red">
<color rgba="1 0 0 1"/>
</material>
</visual>
<visual>
<geometry>
<cylinder length="0.01" radius="0.005"/>
</geometry>
<origin rpy="0 0 0" xyz="0.1 0 0"/>
<material name="red">
<color rgba="1 0 0 1"/>
</material>
</visual>
<collision>
<geometry>
<cylinder length="0.05" radius="0.005"/>
</geometry>
<origin rpy="0 0 0" xyz="0 0 0"/>
<contact_coefficients mu="2.0" kp="2.0" kd="2.0" />
</collision>
<collision>
<geometry>
<cylinder length="0.05" radius="0.005"/>
</geometry>
<origin rpy="0 0 0" xyz="0.1 0 0"/>
<contact_coefficients mu="2.0" kp="2.0" kd="2.0" />
</collision>
<inertial>
<mass value="0.1"/>
<inertia ixx="1e-2" iyy="1e-2" izz="1e-2" ixy="0" ixz="0" iyz="0"/>
</inertial>
</link>
<ros2_control name="GazeboSystem" type="system">
<hardware>
<plugin>gazebo_ros2_control/GazeboSystem</plugin>
</hardware>
<joint name="arm_joint">
<command_interface name="position">
<param name="min">1.79</param>
<param name="max">6.28</param>
</command_interface>
<state_interface name="position"/>
<state_interface name="velocity"/>
</joint>
</ros2_control>
</robot>
joint 제어
from math import sin, cos, pi
import rclpy
from rclpy.node import Node
from rclpy.qos import QoSProfile
from geometry_msgs.msg import Quaternion
from sensor_msgs.msg import JointState
class StatePublisher(Node):
def __init__(self):
rclpy.init()
super().__init__('state_publisher')
qos_profile = QoSProfile(depth=10)
self.joint_pub = self.create_publisher(JointState, 'joint_states', qos_profile)
self.nodeName = self.get_name()
self.get_logger().info("{0} started".format(self.nodeName))
degree = pi / 180.0
loop_rate = self.create_rate(10)
# robot state
tilt_joint = 2.0
tinc = degree
tinc = 0.15
joint_state = JointState()
try:
while rclpy.ok():
rclpy.spin_once(self)
# update joint_state
now = self.get_clock().now()
joint_state.header.stamp = now.to_msg()
joint_state.name = ['tilt_joint']
joint_state.position = [tilt_joint]
self.joint_pub.publish(joint_state)
tilt_joint += tinc
if tilt_joint < 1.8 or tilt_joint > 4.71:
tinc *= -1
# This will adjust as needed per iteration
loop_rate.sleep()
except KeyboardInterrupt:
pass
def main():
node = StatePublisher()
if __name__ == '__main__':
main()
RVIZ 설정
RVIZ에서 로봇 모델이 보이지 않는 경우 RobotModel Display를 추가하고 RobotModel의 Description Topic 항복에 /robot_description 토픽 추가
Panels:
- Class: rviz_common/Displays
Help Height: 85
Name: Displays
Property Tree Widget:
Expanded:
- /Global Options1
- /Status1
- /RobotModel1
Splitter Ratio: 0.5
Tree Height: 711
- Class: rviz_common/Selection
Name: Selection
- Class: rviz_common/Tool Properties
Expanded:
- /2D Goal Pose1
- /Publish Point1
Name: Tool Properties
Splitter Ratio: 0.5886790156364441
- Class: rviz_common/Views
Expanded:
- /Current View1
Name: Views
Splitter Ratio: 0.5
Visualization Manager:
Class: ""
Displays:
- Alpha: 0.5
Cell Size: 1
Class: rviz_default_plugins/Grid
Color: 160; 160; 164
Enabled: true
Line Style:
Line Width: 0.029999999329447746
Value: Lines
Name: Grid
Normal Cell Count: 0
Offset:
X: 0
Y: 0
Z: 0
Plane: XY
Plane Cell Count: 10
Reference Frame: <Fixed Frame>
Value: true
- Alpha: 1
Class: rviz_default_plugins/RobotModel
Collision Enabled: false
Description File: ""
Description Source: Topic
Description Topic:
Depth: 5
Durability Policy: Volatile
History Policy: Keep Last
Reliability Policy: Reliable
Value: /robot_description
Enabled: true
Links:
All Links Enabled: true
Expand Joint Details: false
Expand Link Details: false
Expand Tree: false
Link Tree Style: Links in Alphabetic Order
pan_link:
Alpha: 1
Show Axes: false
Show Trail: false
Value: true
tilt_link:
Alpha: 1
Show Axes: false
Show Trail: false
Value: true
Name: RobotModel
TF Prefix: ""
Update Interval: 0
Value: true
Visual Enabled: true
- Class: rviz_default_plugins/TF
Enabled: true
Frame Timeout: 15
Frames:
All Enabled: true
pan_link:
Value: true
tilt_link:
Value: true
Marker Scale: 1
Name: TF
Show Arrows: true
Show Axes: true
Show Names: false
Tree:
pan_link:
tilt_link:
{}
Update Interval: 0
Value: true
Enabled: true
Global Options:
Background Color: 48; 48; 48
Fixed Frame: pan_link
Frame Rate: 30
Name: root
Tools:
- Class: rviz_default_plugins/Interact
Hide Inactive Objects: true
- Class: rviz_default_plugins/MoveCamera
- Class: rviz_default_plugins/Select
- Class: rviz_default_plugins/FocusCamera
- Class: rviz_default_plugins/Measure
Line color: 128; 128; 0
- Class: rviz_default_plugins/SetInitialPose
Topic:
Depth: 5
Durability Policy: Volatile
History Policy: Keep Last
Reliability Policy: Reliable
Value: /initialpose
- Class: rviz_default_plugins/SetGoal
Topic:
Depth: 5
Durability Policy: Volatile
History Policy: Keep Last
Reliability Policy: Reliable
Value: /goal_pose
- Class: rviz_default_plugins/PublishPoint
Single click: true
Topic:
Depth: 5
Durability Policy: Volatile
History Policy: Keep Last
Reliability Policy: Reliable
Value: /clicked_point
Transformation:
Current:
Class: rviz_default_plugins/TF
Value: true
Views:
Current:
Class: rviz_default_plugins/Orbit
Distance: 2.312662124633789
Enable Stereo Rendering:
Stereo Eye Separation: 0.05999999865889549
Stereo Focal Distance: 1
Swap Stereo Eyes: false
Value: false
Focal Point:
X: 0
Y: 0
Z: 0
Focal Shape Fixed Size: true
Focal Shape Size: 0.05000000074505806
Invert Z Axis: false
Name: Current View
Near Clip Distance: 0.009999999776482582
Pitch: 0.34039855003356934
Target Frame: <Fixed Frame>
Value: Orbit (rviz)
Yaw: 4.750417709350586
Saved: ~
Window Geometry:
Displays:
collapsed: false
Height: 959
Hide Left Dock: false
Hide Right Dock: false
QMainWindow State: 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
Selection:
collapsed: false
Tool Properties:
collapsed: false
Views:
collapsed: false
Width: 3287
X: 4389
Y: 20
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