(Robot_arm)手動發送 Joint Trajectory

 

手動發送 Joint Trajectory

如果要 手動發送 Joint Trajectory 訊息 而不使用 rospy.Publisher，可以直接使用 rostopic pub 指令發送 trajectory_msgs/JointTrajectory 訊息。

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手動發送 Joint Trajectory

bash
rostopic pub -1 /robot_arm_controller/command trajectory_msgs/JointTrajectory '
joint_names: ["joint_1", "joint_2", "joint_3", "joint_4", "joint_5", "joint_6"]
points:
  - positions: [0.2, -0.5, 0.8, -1.2, 0.3, 0.1]
    time_from_start: {secs: 5, nsecs: 0}'

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參數說明

參數	說明
/robot_arm_controller/command	ROS Topic，負責接收 Joint Trajectory 指令
trajectory_msgs/JointTrajectory	訊息類型，包含關節名稱、目標位置與時間
joint_names	指定控制的關節名稱 (需符合 URDF)
points	關節的目標位置
positions	設定目標關節角度
time_from_start	運動完成的時間 (秒)

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測試不同的關節角度

可以更改 positions 值來測試不同的關節運動：

bash
rostopic pub -1 /robot_arm_controller/command trajectory_msgs/JointTrajectory '
joint_names: ["joint_ 1", "joint_2", "joint_3"]
points:
  - positions: [0.0, 0.5, -1.0]
    time_from_start: {secs: 3, nsecs: 0}'

此指令會讓 joint_1, joint_2, joint_3 在 3 秒內移動到新的位置。

這樣可以 不寫 Python 程式碼，直接在終端機手動發送訊息測試機械手臂動作！

#moveit_ws prj 控制關節定義及範例

"joint_1" 鞋軸 前後擺 範圍 (-45 .. +45)

"joint_2" 鞋面 左右擺 範圍 (-45 .. +45)

"joint_3" Y軸行程 前後動 範圍 (-0.170m .. 0m)

"joint_4" X軸行程 左右動 範圍 (-0.120m .. 0m)

"joint_5" Z軸行程 上下動 範圍 (-0.030m .. 0m)

#歸零

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$rostopic pub -1 /robot_arm_controller/command trajectory_msgs/JointTrajectory ' joint_names: ["joint_ 1", "joint_2", "joint_3", "joint_4", "joint_5"]

points: - positions: [0 , 0, 0.0 , 0.0 ,0.0] time_from_start: {secs: 3, nsecs: 0}'

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#joint_1 (move demo)

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$rostopic pub -1 /robot_arm_controller/command trajectory_msgs/JointTrajectory ' joint_names: ["joint_ 1", "joint_2", "joint_3", "joint_4", "joint_5"]

points: - positions: [-45 , 0, 0.0 , 0.0 ,0.0] time_from_start: {secs: 3, nsecs: 0}'

=============================================================

$rostopic pub -1 /robot_arm_controller/command trajectory_msgs/JointTrajectory ' joint_names: ["joint_ 1", "joint_2", "joint_3", "joint_4", "joint_5"]

points: - positions: [45 , 0, 0.0 , 0.0 ,0.0] time_from_start: {secs: 3, nsecs: 0}'

=============================================================

#joint_2 (move demo)

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$rostopic pub -1 /robot_arm_controller/command trajectory_msgs/JointTrajectory ' joint_names: ["joint_ 1", "joint_2", "joint_3", "joint_4", "joint_5"]

points: - positions: [0 ,-45, 0.0 , 0.0 ,0.0] time_from_start: {secs: 3, nsecs: 0}'

=============================================================

$rostopic pub -1 /robot_arm_controller/command trajectory_msgs/JointTrajectory ' joint_names: ["joint_ 1", "joint_2", "joint_3", "joint_4", "joint_5"]

points: - positions: [0 , 45, 0.0 , 0.0 ,0.0]

time_from_start: {secs: 3, nsecs: 0}'

=============================================================

#joint_3 (move demo)

=============================================================

$rostopic pub -1 /robot_arm_controller/command trajectory_msgs/JointTrajectory ' joint_names: ["joint_ 1", "joint_2", "joint_3", "joint_4", "joint_5"]

points: - positions: [0 , 0, -0.080 , 0.0 ,0.0] time_from_start: {secs: 3, nsecs: 0}'

=============================================================

$rostopic pub -1 /robot_arm_controller/command trajectory_msgs/JointTrajectory ' joint_names: ["joint_ 1", "joint_2", "joint_3", "joint_4", "joint_5"]

points: - positions: [0 , 0, -0.170 , 0.0 ,0.0]

time_from_start: {secs: 3, nsecs: 0}'

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#joint_4 (move demo)

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$rostopic pub -1 /robot_arm_controller/command trajectory_msgs/JointTrajectory ' joint_names: ["joint_ 1", "joint_2", "joint_3", "joint_4", "joint_5"]

points: - positions: [0 , 0, 0.0 , -0.060 ,0.0] time_from_start: {secs: 3, nsecs: 0}'

=============================================================

$rostopic pub -1 /robot_arm_controller/command trajectory_msgs/JointTrajectory ' joint_names: ["joint_ 1", "joint_2", "joint_3", "joint_4", "joint_5"]

points: - positions: [0 , 0, 0.0 , -0.120 ,0.0]

time_from_start: {secs: 3, nsecs: 0}'

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#joint_5 (move demo)

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$rostopic pub -1 /robot_arm_controller/command trajectory_msgs/JointTrajectory ' joint_names: ["joint_ 1", "joint_2", "joint_3", "joint_4", "joint_5"]

points: - positions: [0 , 0, 0.0 , 0.0 , -0.015] time_from_start: {secs: 3, nsecs: 0}'

=============================================================

$rostopic pub -1 /robot_arm_controller/command trajectory_msgs/JointTrajectory ' joint_names: ["joint_ 1", "joint_2", "joint_3", "joint_4", "joint_5"]

points: - positions: [0 , 0, 0.0 , 0.0 ,-0.030]

time_from_start: {secs: 3, nsecs: 0}'

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