From e5fa7d4d58928c48d7b52dfa48bf0e09e0bf68d7 Mon Sep 17 00:00:00 2001 From: Andrew Parker <40184088+aparker-fetch@users.noreply.github.com> Date: Fri, 8 Feb 2019 15:32:26 -0800 Subject: [PATCH] add deadzone param workaround to teleop.rst (#61) --- source/teleop.rst | 22 ++++++++++++++++++++++ 1 file changed, 22 insertions(+) diff --git a/source/teleop.rst b/source/teleop.rst index 25a89cc..0c99973 100644 --- a/source/teleop.rst +++ b/source/teleop.rst @@ -178,3 +178,25 @@ USB cable, and then running: This situation is most often caused by charging the robot joystick from the USB port of another computer. + +Using Deadzone Parameter to Correct Drift +----------------------------------------- + +Some controllers have poorly-zeroed joysticks, meaning that they send a nonzero +value when the joystick is untouched and ought to send a zero value. This will be +apparent if you press the deadman button on the controller, and the robot slowly +moves without any input to the joysticks. + +This behavior can be compensated for by using a rosparameter: **joy/deadzone** +(`ROS docs `_), which defines the amount by +which the joystick has to move before it is considered to be off-center, specified +relative to an axis normalized between -1 and 1. + +Add/set the parameter in ``/etc/ros/DISTRO/robot.launch``:: + + + + + +You can inspect the output of ``rostopic echo /joy`` with the controller +connected to choose an appropriate value for your controller.