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I used the rostopic echo /joint_states to get the trajectory. And I want to make fetch move following the specified trajectory. But when I run the following python code, fetch i gazebo did not move at all. (but the value of joint_states changed as the specified trajectory )

step 1：roslaunch fetch_gazebo playground.launch
step 2 ：run the following python code

import rospy
from sensor_msgs.msg import JointState
from std_msgs.msg import String

def talker():
rospy.init_node('talker', anonymous=True)
pub = rospy.Publisher('/joint_states', JointState, queue_size=1)
rate = rospy.Rate(10)
States=JointState();

while not rospy.is_shutdown():
    States.header.stamp = rospy.Time.now()
    States.name=['l_wheel_joint', 'r_wheel_joint', 'torso_lift_joint', 'bellows_joint', 'head_pan_joint', 'head_tilt_joint','shoulder_pan_joint', 'shoulder_lift_joint', 'upperarm_roll_joint', 'elbow_flex_joint',  'forearm_roll_joint', 'wrist_flex_joint', 'wrist_roll_joint', 'l_gripper_finger_joint', 'r_gripper_finger_joint']
    States.position=[2.3345511882210843, -0.634820929568157, 1.3874957609389449e-11, 0.006625115661578738, -0.006317351703414076, 0.6313382345293581, 1.318234031118565, 1.3956276493932007, -0.2089051625781302, 1.7008202010543583, -0.016423456036472217, 1.6468142324488904, -0.008023511866540822, 0.02927438379458224, 0.02988700000824869]
    States.velocity=[12.07760822395682, 12.531155056815715, 0.00551848394843501, -0.006297094941102944, -0.027727924188788666, -0.8389266373685278, -0.01006305278808928, 0.06190390257346417, 0.014009208799648233, 0.046633352775736804, -0.016161009170007727, 0.08276079812692123, -0.01060212434698555, -0.003579291965645062, 0.003610553717902847]
    States.effort=[8.85, 8.85, -450.0, -1.4943480513086147, 0.09047042943010608, -0.10530705118107508, -1.8543929008080047, 8.507774908689282, 1.273713991824661, 14.859113858920301, -7.935003515304931, -6.557514430844646, -1.7112672692034643, -9.663865221953854, -10.336134778046146]
    pub.publish(States)
    print (States)

if name == 'main':
try:
talker()
except rospy.ROSInterruptException:
pass

A customer is struggling to use MoveIt. We need a tutorial showing how to write a simple python script to use MoveIt to move the arm to a cartesian pose.

We've now open sourced https://github.com/fetchrobotics/fetch_open_auto_dock.

I think the section http://docs.fetchrobotics.com/docking.html needs some updating.

Following the tutorial , it is easy to move the torso of fetch using move_group("arm_with_torso") in joint space.

However, if I firstly would like to raise the torso to some prefer height then fix the torso to control the arm only. What should I do? I have tried two move_groups.

When using move_group("arm"), the torso would move back to zero immediately after the move_group.execute(plan) instructions.

If move_group("arm_with_torso") is used, if I set the goal pose to the move_group, then the fetch arm will move with torso joint.

What should I do in this situation?

Best wishes!

We should add a faq page that includes:

• battery charging when breaker switch off
• software breaker information
• smooth trajectory and breaker fault note

PS4 controller does not work after we upgrade to 18.04. http://docs.fetchrobotics.com/indigo_to_melodic.html does not say anything but:

Check whether your PS3 controller pairs and controls the robot.

Important note: The PS3 controller currently won’t work with ROS by default. To fix this, run sudo ln -s /dev/input/js0 /dev/ps3joy. We hope to fix this by fixing the corresponding udev rules eventually.

Important note: for 18.04 the robots have switched from using sixad to using PS3joy. Some changes in behaviour you may see:

The LEDs on the PS3 controller may continually blink, even though it is connected.
Inputs may not be sent from the PS3 controller if the accelerometers in the controller do not detect motion. This can result in jerky motion when using the controller.
We are hoping to determine fixes for these in the near future.

There is an old command here http://docs.fetchrobotics.com/in_the_box.html?highlight=pair sudo sixpair, but does not apply anymore.

@erelson

Under "gripper interface", the docs say:

"gripper_controller/command exposes a..."

that should read

"gripper_controller/gripper_action exposes a..."

The new arm teleop was merged here:
ZebraDevs/fetch_ros#61
Which adds Cartesian control mode to move the arm, and did not include documentation.

Additional changes were added for safety here:
ZebraDevs/fetch_ros#95 (Indigo)
ZebraDevs/fetch_ros#92 (Melodic)

Missing from our documentation is how to use this new feature.

Button 9 name: Linear Arm Motion
Button 11 name: Angular Arm Motion

We followed the guide here and double checked every step but every time we turn on the robot we have to run sudo service roscore start manually. However, we don't have to run sudo service robot start, which will start after roscore.

@erelson

Solution: sudo systemctl set-default multi-user.target

Important note... this may break the ability to use a monitor with your robot... This can be reverted with sudo systemctl set-default graphical.target and then rebooting. More TBD.

Please make this section into a a note:

One notable charging error is caused by the Power Disconnect Switch being switched off. When the power disconnect is switch off, it disconnects the battery which prevents the charger from working. When the charger detects this situation it will flash both the charge indicator red, and the power button at the same time.

a ticket was filed related to this problem and it should be highlighted better

this info needs to be added to the research docs

Currently the documentation starts with how to run the simulator for navigation but then doesn't explicitly call out that the commands can be run on a real robot...

http://docs.fetchrobotics.com/navigation.html

It took me a bit to realize I wasn't referencing the param for the fetch_teleop node correctly. It wasn't until I looked again at the source as well as a launch file in startup that I realized I wasn't using the Teleop Component namespace prefix. Could this be better documented, say in that package or teleop page?

e.g:

  <node name="teleop" pkg="fetch_teleop" type="joystick_teleop">
-    <param name="button_deadman" value="4"/>
+    <param name="base/button_deadman" value="4"/>
  </node>

it looks like you need to build with make latexpdf to generate the pdf

fetch_arm_fall.zip

The arm is first moved into an upright position using moveit and then for a period of a few seconds afterwards, if the torso is at all moved up, the arm will start to fall. It also falls if the torso is moved down to a certain point within that same period of time. The attached video (zipped) demonstrates that. I use the controller to move the torso. We're not sure if it is an issue with moveit, or with the robot. Some insight would be appreciated.

We are using 18.04

(I was told to make an issue here, but if there would be a better place to do that please let me know)

I got an "error 404" when installing fetch packages on a Fetch robot (of the robot type " fetch-generic"). I followed the manual installation instructions on the official Fetch website, and got the error at the step linked here.

The website mentioned (http://packages.fetchrobotics.com/binaries/) does not seem to exist so the packages cannot be installed. Can you help me with this so I can download the necessary packages?

University of Tokyo was teleoping the robot and got near an obstacle. Then the robot would not drive forwared, which was confusing. We should document the safety feature that we have added to the teleop and add it to the FAQ

Hi,

I had this situation described at https://github.com/fetchrobotics/docs/blame/feac201dfde2b380a5d9af89b316024f4c53c4e7/source/care_and_feeding.rst#L44

In some cases, the charging circuit may detect an error condition and will flash the charging indicator red. After about 1 minute, the charger will attempt charging again. If the error condition persists, a support ticket should be created to address the problem.

The robot just arrived this morning and we can run with joystick for a while, after ~10 - ~30 minuets, we realized that a robot did not respond. what we tried is;

• we can pair / dis-pair the joystick, it vibrate.
• we can not see any output from HDMI cable
• we connected the laptop to the service ether cable port, and set IP of the laptop to the 10.42.42.100, but ping 10.42.42.42 did not respond.

please add a page with how to contact research support and information needed to file a ticket. It should show up in the main sidebar navigation

• battery_state
• robot_state
• ???

In the video at http://docs.fetchrobotics.com/in_the_box.html we do not mention the pallet that the crate (sometimes) ships on. One important note is to remove the crate from the pallet before rolling the robot down the ramp, as while the crate is on the pallet, the ramp is at a steep angle that risks damaging skins.

@daviddymesich can we easily add a warning in the unpacking video? If not, we can add a warning before the video on the page.

The default sudo password for the fetch robot is not included in the manual. What is the password?

@ablasdel (i can't seem to assign this ticket to you but...) we've had several releases but none of the notes are consolidated in the documentation.