webots和ros2笔记03-解析
在完成02-启程：https://zhangrelay.blog.csdn.net/article/details/112675018
那么会思考两个机械臂拿起易拉罐的过程是如何实现了。
简要分析一下：
launch（armed_robots.launch.py）：
import os
import launch
from ament_index_python.packages import get_package_share_directory
from webots_ros2_core.utils import ControllerLauncher
from webots_ros2_core.webots_launcher import WebotsLauncher
def generate_launch_description():
# Webots
webots = WebotsLauncher(world=os.path.join(get_package_share_directory('webots_ros2_demos'), 'worlds', 'armed_robots.wbt'))
# Controller nodes
synchronization = launch.substitutions.LaunchConfiguration('synchronization', default=False)
abb_controller = ControllerLauncher(
package='webots_ros2_core',
executable='webots_robotic_arm_node',
arguments=['--webots-robot-name=abbirb4600'],
parameters=[{'synchronization': synchronization, 'controller_name': 'abb'}],
output='screen'
)
ure5_controller = ControllerLauncher(
package='webots_ros2_core',
executable='webots_robotic_arm_node',
arguments=['--webots-robot-name=UR5e'],
parameters=[{'synchronization': synchronization, 'controller_name': 'ur'}],
output='screen'
)
# Control nodes
armed_robots_ur = ControllerLauncher(
package='webots_ros2_demos',
executable='armed_robots_ur',
output='screen'
)
armed_robots_abb = ControllerLauncher(
package='webots_ros2_demos',
executable='armed_robots_abb',
output='screen'
)
return launch.LaunchDescription([
webots, abb_controller, ure5_controller, armed_robots_ur, armed_robots_abb,
launch.actions.RegisterEventHandler(
event_handler=launch.event_handlers.OnProcessExit(
target_action=webots,
on_exit=[launch.actions.EmitEvent(event=launch.events.Shutdown())],
)
),
])
启动环境和机械臂：
成功
失败
使用world下armed_robots环境文件。
# Webots
webots = WebotsLauncher(world=os.path.join(get_package_share_directory('webots_ros2_demos'), 'worlds', 'armed_robots.wbt'))控制器节点（两个机械臂分别为ur和abb）：
ur：
ure5_controller = ControllerLauncher(
package='webots_ros2_core',
executable='webots_robotic_arm_node',
arguments=['--webots-robot-name=UR5e'],
parameters=[{'synchronization': synchronization, 'controller_name': 'ur'}],
output='screen'
)abb：
abb_controller = ControllerLauncher(
package='webots_ros2_core',
executable='webots_robotic_arm_node',
arguments=['--webots-robot-name=abbirb4600'],
parameters=[{'synchronization': synchronization, 'controller_name': 'abb'}],
output='screen'
)这里需要注意（synchronization同步）两个机械臂要同步运动否则无法协调完成任务。
控制器不同于控制，对于两个机械臂有具体的控制节点完成对应的控制指令，如下：
ur：
armed_robots_ur = ControllerLauncher(
package='webots_ros2_demos',
executable='armed_robots_ur',
output='screen'
)具体指令为一系列轨迹和抓取动作坐标。
import rclpy
from webots_ros2_demos.follow_joint_trajectory_client import FollowJointTrajectoryClient
def main(args=None):
rclpy.init(args=args)
armed_robot_ur = FollowJointTrajectoryClient('armed_robots_ur', '/ur/follow_joint_trajectory')
armed_robot_ur.send_goal({
'joint_names': [
'shoulder_pan_joint',
'shoulder_lift_joint',
'elbow_joint',
'wrist_1_joint',
'finger_1_joint_1',
'finger_2_joint_1',
'finger_middle_joint_1'
],
'points': [
{
'positions': [0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0],
'velocities': [5] * 7,
'accelerations': [5] * 7,
'time_from_start': {'sec': 3, 'nanosec': 0}
},
{
'positions': [0.0, 0.0, 0.0, 0.0, 0.85, 0.85, 0.6],
'velocities': [5] * 7,
'accelerations': [5] * 7,
'time_from_start': {'sec': 4, 'nanosec': 0}
},
{
'positions': [0.63, -2.26, -1.88, -2.14, 0.85, 0.85, 0.6],
'velocities': [5] * 7,
'accelerations': [5] * 7,
'time_from_start': {'sec': 5, 'nanosec': 0}
},
{
'positions': [0.63, -2.26, -1.88, -2.14, 0.0, 0.0, 0.0],
'velocities': [5] * 7,
'accelerations': [5] * 7,
'time_from_start': {'sec': 6, 'nanosec': 0}
},
{
'positions': [0.63, -2.0, -1.88, -2.14, 0.0, 0.0, 0.0],
'velocities': [5] * 7,
'accelerations': [5] * 7,
'time_from_start': {'sec': 7, 'nanosec': 0}
},
{
'positions': [0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0],
'velocities': [5] * 7,
'accelerations': [5] * 7,
'time_from_start': {'sec': 8, 'nanosec': 0}
},
{
'positions': [0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0],
'velocities': [5] * 7,
'accelerations': [5] * 7,
'time_from_start': {'sec': 9, 'nanosec': 0}
}
]
}, 10)
rclpy.spin(armed_robot_ur)
if __name__ == '__main__':
main()要能够知道位置指令中抓取部分：
{
'positions': [0.0, 0.0, 0.0, 0.0, 0.85, 0.85, 0.6],
'velocities': [5] * 7,
'accelerations': [5] * 7,
'time_from_start': {'sec': 4, 'nanosec': 0}
},
{
'positions': [0.63, -2.26, -1.88, -2.14, 0.85, 0.85, 0.6],
'velocities': [5] * 7,
'accelerations': [5] * 7,
'time_from_start': {'sec': 5, 'nanosec': 0}
},abb：
armed_robots_abb = ControllerLauncher(
package='webots_ros2_demos',
executable='armed_robots_abb',
output='screen'
)具体指令为一系列轨迹和抓取动作坐标。
import rclpy
from webots_ros2_demos.follow_joint_trajectory_client import FollowJointTrajectoryClient
def main(args=None):
rclpy.init(args=args)
armed_robot_abb = FollowJointTrajectoryClient('armed_robots_abb', '/abb/follow_joint_trajectory')
armed_robot_abb.send_goal({
'joint_names': [
'A motor',
'B motor',
'C motor',
'E motor',
'finger_1_joint_1',
'finger_2_joint_1',
'finger_middle_joint_1'
],
'points': [
{
'positions': [0.0, 0.0, 0.0, 0., 0.0, 0.0, 0.0],
'velocities': [5] * 7,
'accelerations': [5] * 7,
'time_from_start': {'sec': 0, 'nanosec': 0}
},
{
'positions': [-0.025, 0.0, 0.82, -0.86, 0.0, 0.0, 0.0],
'velocities': [5] * 7,
'accelerations': [5] * 7,
'time_from_start': {'sec': 1, 'nanosec': 0}
},
{
'positions': [-0.025, 0.1, 0.82, -0.86, 0.0, 0.0, 0.0],
'velocities': [5] * 7,
'accelerations': [5] * 7,
'time_from_start': {'sec': 2, 'nanosec': 0}
},
{
'positions': [-0.025, 0.1, 0.82, -0.86, 0.85, 0.85, 0.6],
'velocities': [5] * 7,
'accelerations': [5] * 7,
'time_from_start': {'sec': 3, 'nanosec': 0}
},
{
'positions': [-0.025, -0.44, 0.82, -0.86, 0.85, 0.85, 0.6],
'velocities': [5] * 7,
'accelerations': [5] * 7,
'time_from_start': {'sec': 4, 'nanosec': 0}
},
{
'positions': [1.57, -0.1, 0.95, -0.71, 0.85, 0.85, 0.6],
'velocities': [5] * 7,
'accelerations': [5] * 7,
'time_from_start': {'sec': 5, 'nanosec': 0}
},
{
'positions': [1.57, -0.1, 0.8, -0.81, 0.0, 0.0, 0.0],
'velocities': [5] * 7,
'accelerations': [5] * 7,
'time_from_start': {'sec': 6, 'nanosec': 0}
},
{
'positions': [0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0],
'velocities': [5] * 7,
'accelerations': [5] * 7,
'time_from_start': {'sec': 7, 'nanosec': 0}
},
{
'positions': [0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0],
'velocities': [5] * 7,
'accelerations': [5] * 7,
'time_from_start': {'sec': 9, 'nanosec': 0}
}
]
}, 10)
rclpy.spin(armed_robot_abb)
if __name__ == '__main__':
main()更多内容和教程，稍后补充。
- C:\ros_ws\webots2>ros2 launch webots_ros2_tutorials line_following_launch.py
