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Running showcase applications

Description: Short tutorial on running some apps ready to launch as showcase.

Tutorial Level: BEGINNER

Preparing hardware

At first, you have to start Elektron (switch on its left side to ON) and power up EeePC. Next make sure, that all devices are connected (one USB hub, Kinect and SICK laser) and powered. Last step is pressing red button on the left side - if LED on internal PCB toggles from red to green, then everything is OK and you're ready to go!

Best way to operate Elektron robot is to use SSH, so open some consoles and connect to EeePC:

ssh eee@eee2

Launching base drivers

To start motor drivers, call (on first console):

roslaunch elektron_bringup elektron_base.launch

This is base driver, and without it Elektron wont move.

Simple teleoperation

There are two ways to operate Elektron: using joystick or keyboard. Preferred way is to use joystick, because it's receiver is connected directly to robot's computer and it wont suffer when WiFi loses signal.

See also: elektron_teleop package.

Joystick

Before using joystick, make sure that there is receiver connected to EeePC. To start teleoperation node, call (on second console):

roslaunch elektron_teleop teleop_joy.launch

First axis is used for both linear and angular velocity control, other buttons are unused for now.

Keyboard

Keyboard is recommended only when robot operates in close range to access point and WiFi signal is strong, otherwise ssh conection may be interrupted and teleoperation will break.

To start keyboard teleoperation call:

rosrun elektron_teleop elektron_teleop_keyboard

Use WASD keys to move, hold shift to move faster. Tap space to immediately stop robot.

Obstacle avoidance

There are to sources from which Elektron can detect obstacles: SICK laser and Kinect. Both of them can be used with simple obstacle avoidance application.

Starting sensors

To start SICK laser, call:

roslaunch elektron_bringup elektron_sensors.launch

Alternatively, you can use Kinect to simulate laser scan reading, just call:

roslaunch pcl_to_scan kinect_laser.launch

Running obstacle avoidance algorithm

rosrun laser_avoid laser_avoid


2020-02-22 12:41