I can‘t  get the pose of end effector

There is a function to get the pose of end effector in the skill.py of realman as bellow:
gripper_pose = arm.robot.rm_get_current_arm_state()[1]["pose"]

But I print the gripper_pose, it shows [0.0, 0.0, 0.0, 0.0, 0.0, 0.0]
 Why I cant get the gripper_pose.
realman arm:RM65
Robotic-Arm==1.0.6
control version:1.6.5