Follow-me with ADBSCAN on Aaeon Robot#

This tutorial provides instructions for running the ADBSCAN-based Follow-me algorithm from Autonomous Mobile Robot using Intel® RealSense™ camera input. Validation of the algorithm was performed on a custom Aaeon robot. The Intel® RealSense™ camera publishes to /camera/depth/color/points topic. The adbscan_sub_node subscribes to the corresponding topic, detects the obstacle array, computes the robot’s velocity and publishes to the /cmd_vel topic of type geometry_msg/msg/Twist. This twist message consists of the updated angular and linear velocity of the robot to follow the target, which can be subsequently subscribed by a robot-driver.

Getting Started#

Prerequisites#

  • Assemble your robotic kit following the instructions provided by AAEON.

  • Complete the get started guide before continuing.

Install the Deb package#

Install the ros-jazzy-follow-me-tutorial Deb package from the Intel® Autonomous Mobile Robot APT repository.

sudo apt update
sudo apt install ros-jazzy-follow-me-tutorial

sudo apt update
sudo apt install ros-humble-follow-me-tutorial

Calibrate the robot#

Please perform IMU calibration of the robot, launch script below:

source /opt/ros/jazzy/setup.bash
/opt/ros/jazzy/share/ros2_amr_interface/scripts/calibration.sh

source /opt/ros/humble/setup.bash
/opt/ros/humble/share/ros2_amr_interface/scripts/calibration.sh

Run Demo#

To launch the Follow-me application tutorial on the Aaeon robot, use the following ROS 2 launch file.

source /opt/ros/jazzy/setup.bash
ros2 launch tutorial_follow_me aaeon_followme_launch.py

source /opt/ros/humble/setup.bash
ros2 launch tutorial_follow_me aaeon_followme_launch.py

After executing the above command, you can observe that the robot detecting the target within a tracking radius (~0.5 - 1.5 m; min_dist and max_dist are set in /opt/ros/jazzy/share/tutorial_follow_me/params/followme_adbscan_RS_params.yaml) and subsequently following the moving target person.

There are reconfigurable parameters in the /opt/ros/jazzy/share/tutorial_follow_me/params/followme_adbscan_RS_params.yaml file. The user can modify the parameters depending on the respective robot, sensor configuration and environments (if required) before running the tutorial. Find a brief description of the parameters in the following list.

  • Lidar_type

    Type of the point cloud sensor. For Intel® RealSense™ camera and LIDAR inputs, the default value is set to RS and 2D, respectively.

  • Lidar_topic

    Name of the topic publishing point cloud data.

  • Verbose

    If this flag is set to True, the locations of the detected target objects will be printed as the screen log.

  • subsample_ratio

    This is the downsampling rate of the original point cloud data. Default value = 15 (i.e. every 15-th data in the original point cloud is sampled and passed to the core ADBSCAN algorithm).

  • x_filter_back

    Point cloud data with x-coordinate > x_filter_back are filtered out (positive x direction lies in front of the robot).

  • y_filter_left, y_filter_right

    Point cloud data with y-coordinate > y_filter_left and y-coordinate < y_filter_right are filtered out (positive y-direction is to the left of robot and vice versa).

  • z_filter

    Point cloud data with z-coordinate < z_filter will be filtered out. This option will be ignored in case of 2D Lidar.

  • Z_based_ground_removal

    Filtering in the z-direction will be applied only if this value is non-zero. This option will be ignored in case of 2D Lidar.

  • base, coeff_1, coeff_2, scale_factor

    These are the coefficients used to calculate adaptive parameters of the ADBSCAN algorithm. These values are pre-computed and recommended to keep unchanged.

  • init_tgt_loc

    This value describes the initial target location. The person needs to be at a distance of init_tgt_loc in front of the robot to initiate the motor.

  • max_dist

    This is the maximum distance that the robot can follow. If the person moves at a distance > max_dist, the robot will stop following.

  • min_dist

    This value describes the safe distance the robot will always maintain with the target person. If the person moves closer than min_dist, the robot stops following.

  • max_linear

    Maximum linear velocity of the robot.

  • max_angular

    Maximum angular velocity of the robot.

  • max_frame_blocked

    The robot will keep following the target for max_frame_blocked number of frames in the event of a temporary occlusion.

  • tracking_radius

    The robot will keep following the target as long as the current target location = previous location +/- tracking_radius

Troubleshooting#

  • Failed to install Deb package: Please make sure to run sudo apt update before installing the necessary Deb packages.

  • You may stop the demo anytime by pressing ctrl-C.

  • If the robot rotates more than intended at each step, try reducing the parameter max_angular in the parameter file.

  • For general robot issues, refer to Troubleshooting.

  • If the motor controller board does not start, restart the robot.