Frequent questions¶
This section presents some common problems and how to solve them!
Installation and compilation problems¶
- If you want to change default GCC compiler to version 5, open a terminal and run:
export CC=/usr/bin/gcc-5
export CXX=/usr/bin/g++-5
then you can compile using GCC 5.
- If you want to grant root access to GPIO for any executable:
cd devel/lib/robot_micro # cd to the directory with your node
sudo chown root:root my_node # change ownship to root
sudo chmod a+rx my_node # set as executable by all
sudo chmod u+s my_node # set the setuid bit
For example:
sudo chown root:root devel/lib/robot_micro/robot_twist_subscriber
sudo chmod a+rx devel/lib/robot_micro/robot_twist_subscriber
sudo chmod u+s devel/lib/robot_micro/robot_twist_subscriber
- If you want to remove password with sudo for current user:
edit: .. code-block:: none
sudo nano /etc/sudoers
add to end file: user_name ALL=(ALL) NOPASSWD: ALL
ubuntu ALL=(ALL) NOPASSWD: ALL
- If you want to grant root access to cameras and serial ports:
create a udev rule file:
sudo nano /etc/udev/rules.d/40-permissions.rules
insert content:
KERNEL=="ttyUSB0", MODE="0666"
KERNEL=="ttyUSB1", MODE="0666"
KERNEL=="ttyUSB2", MODE="0666"
KERNEL=="ttyUSB3", MODE="0666"
KERNEL=="ttyACM0", MODE="0666"
KERNEL=="video0", MODE="0666"
For Raspberry pi Cam:
KERNEL=="vchiq", MODE="0666"
Interface problems¶
- When I close a node that uses gazebo, it takes too long before it closes.
Answer: You can close manually the process, run in a separate command window:
sudo killall gzserver gzclient