Week 4 (3rd Period)

António Morais
3rd Period - Weekly Progress
March 10, 2024

Website development

During the first week since the start of the 2^nd semester and along with it, the ElectroCap Challenge, the team focused on launching the current website this is written on. As of now, it is still a very early version of the website and we already have feedback to start changing how it looks and it’s contents.

3D Mapping

→ A-LOAM

Thinking about Week 3 (3^rd Period) problems encountered the team studied more in depth the algorithm and found that the anomaly stemmed from discrepancies in the algorithm’s code, particularly in the handling of .frame_id parameters, necessitating adjustments to accommodate variations across different versions of ROS.

// As an example
laserOdometry.header.frame_id = "/camera_init"; // ROS Melodic or Kinetic
laserOdometry.header.frame_id = "camera_init"; // ROS Noetic

With these modifications implemented throughout the codebase, the algorithm successfully processed the dataset (nsh_indoor_outdoor.bag), culminating in the generation of the subsequent 3D map:

alter-text — Figure 1 - Map obtained utilizing the A-LOAM algorithm alongside one of the datasets provided by the authors.

Subsequently, the team directed its efforts towards executing the algorithm within the TIAGo’s simulation environment developed by SocRob@Home. Easing this transition merely required supplying the algorithm with the data acquired by the Ouster LiDAR in simulation. To accomplish this, we identified the topic where the Ouster data is published:

// File path: A-LOAM/src/scanRegistration.cpp
ros::Subscriber subLaserCloud = nh.subscribe<sensor_msgs::PointCloud2>("/velodyne_points", 100, laserCloudHandler); // No changes
ros::Subscriber subLaserCloud = nh.subscribe<sensor_msgs::PointCloud2>("/ouster/points", 100, laserCloudHandler); // With changes