Examples: Movement
This document shows how to control Ned in order to make Move Joints & Move Pose.
If you want to see more, you can look at PyNiryo - Joints & Pose
Important
In the following sections, you are supposed to be already connected to a calibrated robot.
The robot’s instance is saved in the variable robot
. To know how to do so, go
look at section Examples: Basics.
Danger
If you are using the real robot, make sure the environment around it is clear.
Joints
Move Joints
To make a moveJ, you can either provide:
6 floats :
j1, j2, j3, j4, j5, j6
a list of 6 floats :
[j1, j2, j3, j4, j5, j6]
It is possible to provide these parameters to the function move_joints()
or via the joints
setter, at your convenience:
# Moving Joints with function & 6 floats
robot.move_joints(0.0, 0.0, 0.0, 0.0, 0.0, 0.0)
# Moving Joints with function & a list of floats
robot.move_joints([-0.5, -0.6, 0.0, 0.3, 0.0, 0.0])
# Moving Joints with setter & 6 floats
robot.joints = 0.2, -0.4, 0.0, 0.0, 0.0, 0.0
# Moving Joints with setter & a list of floats
robot.joints = [-0.2, 0.3, 0.2, 0.3, -0.6, 0.0]
You should note that these 4 commands are doing exactly the same thing! In your future scripts, chose the one you prefer, but try to remain consistent to keep a good readability.
Get Joints
To get actual joint positions, you can use the function get_joints()
or the joints
getter. Both will return a list of the 6 joints position:
# Getting Joints with function
joints_read = robot.get_joints()
# Getting Joints with getter
joints_read = robot.joints
Hint
As we are developing in Python, we can unpack list very easily, which means that
we can retrieve joints value in 6 variables by writing j1, j2, j3, j4, j5, j6 = robot.get_joints()
.
Pose
Move Pose
To perform a moveP, you can provide:
6 floats : x, y, z, roll, pitch, yaw
a list of 6 floats : [x, y, z, roll, pitch, yaw]
As for MoveJ, it is possible to provide these parameters
to the function move_pose()
or the pose
setter, at your convenience:
pose_target = [0.2, 0.0, 0.2, 0.0, 0.0, 0.0]
pose_target_obj = PoseObject(0.2, 0.0, 0.2, 0.0, 0.0, 0.0)
# Moving Pose with function
robot.move_pose(0.2, 0.0, 0.2, 0.0, 0.0, 0.0)
robot.move_pose(pose_target)
robot.move_pose(pose_target_obj)
# Moving Pose with setter
robot.pose = (0.2, 0.0, 0.2, 0.0, 0.0, 0.0)
robot.pose = pose_target
robot.pose = pose_target_obj
Each of these 6 commands are doing the same thing.
Get Pose
To get end effector actual pose, you can use
the function get_pose()
or the pose
getter. Both will return a PoseObject
:
# Getting Joints with function
pose_read = robot.get_pose()
# Getting Joints with getter
pose_read = robot.pose
How to use the PoseObject
The PoseObject
is a Python object which allows to store all poses’ 6 coordinates (x, y, z,
roll, pitch, yaw) in one single instance.
It can be converted into a list if needed with the method
to_list()
.
It also allows to create new PoseObject
with some offset, much easier than
copying list and editing only 1 or 2 values.
For instance, imagine that we want to shift the place pose by 5 centimeters at each iteration of a loop,
you can use the copy_with_offsets()
method:
pick_pose = PoseObject(
x=0.30, y=0.0, z=0.15,
roll=0, pitch=1.57, yaw=0.0
)
first_place_pose = PoseObject(
x=0.0, y=0.2, z=0.15,
roll=0, pitch=1.57, yaw=0.0
)
for i in range(5):
robot.move_pose(pick_pose)
new_place_pose = first_place_pose.copy_with_offsets(x_offset=0.05 * i)
robot.move_pose(new_place_pose)