Test code used at https://github.com/jsk-ros-pkg/jsk_pr2eus/pull/460#issuecomment-975418370

dummy_fjt_client_fetch.py

#!/usr/bin/env python

import rospy
from control_msgs.msg import FollowJointTrajectoryActionGoal
from trajectory_msgs.msg import JointTrajectoryPoint

rospy.init_node('dummy_fjt_client')
pub = rospy.Publisher(
        "/arm_controller/follow_joint_trajectory/goal",
        FollowJointTrajectoryActionGoal,
        queue_size=1)


def move_fetch(pos, time):
    now = rospy.Time.now()
    goal = FollowJointTrajectoryActionGoal()
    goal.header.stamp = now
    goal.goal.trajectory.header.stamp = now
    joint_names = [
        'shoulder_pan_joint',
        'shoulder_lift_joint',
        'upperarm_roll_joint',
        'elbow_flex_joint',
        'forearm_roll_joint',
        'wrist_flex_joint',
        'wrist_roll_joint']
    goal.goal.trajectory.joint_names = joint_names
    point = JointTrajectoryPoint()
    point.positions = [pos] * len(joint_names)
    point.velocities = [0] * len(joint_names)
    point.accelerations = [0] * len(joint_names)
    point.time_from_start = rospy.Time.from_sec(time)
    goal.goal.trajectory.points = [point]
    pub.publish(goal)


# Do not forget to set fetch init pose before calling these lines
rospy.sleep(1)
move_fetch(0.0, 10)  # init pose
rospy.sleep(1)
move_fetch(0.1, 10)  # move little from init pose