NAV2 AMCL Fails to Localize my Custom Ackermann Robot

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I'm experiencing issues with the AMCL localization of my custom Ackermann robot using Nav2. In RViz, the localization fails, and I'm unsure about the root cause. I've identified several potential factors:

1. AMCL Configuration: Currently the robot_model_type parameter in the AMCL configuration is set to "differential", as I couldn't find an Ackermann option available in the documentation: AMCL configuration. Here is my current AMCL configuration.

2. Parameter Misconfiguration : I've tried to adjust the parameters to match my robot's real-world characteristics as closely as possible, but I may have misconfigured something. My robot has a higher laser range and larger size than a TurtleBot, and it operates in a larger environment. I'm unsure about the correct settings for parameters like scan_buffer_maximum_scan_distance, link_scan_maximum_distance, and loop_search_maximum_distance in the mapper_params_online_sync.yaml file. You can also refer to my nav2_params.yaml file for other settings:

amcl:
  ros__parameters:
    use_sim_time: True
    alpha1: 0.2
    alpha2: 0.2
    alpha3: 0.2
    alpha4: 0.2
    alpha5: 0.2
    base_frame_id: "base_footprint"
    beam_skip_distance: 0.5
    beam_skip_error_threshold: 0.9
    beam_skip_threshold: 0.3
    do_beamskip: false
    global_frame_id: "map"
    lambda_short: 0.1
    laser_likelihood_max_dist: 2.0
    laser_max_range: 100.0
    laser_min_range: -1.0
    laser_model_type: "likelihood_field"
    max_beams: 60
    max_particles: 2000
    min_particles: 500
    odom_frame_id: "odom"
    pf_err: 0.05
    pf_z: 0.99
    recovery_alpha_fast: 0.0
    recovery_alpha_slow: 0.0
    resample_interval: 1
    robot_model_type: "differential" #Need to customize

later an Ackermman plugin for this according to the documentation: https://navigation.ros.org/configurat... save_pose_rate: 0.5 sigma_hit: 0.2 tf_broadcast: true transform_tolerance: 1.0 update_min_a: 0.2 update_min_d: 0.25 z_hit: 0.5 z_max: 0.05 z_rand: 0.5 z_short: 0.05 scan_topic: scan

Here is my nav2_params.yaml and mapper_params_online_sync.yaml) files.

3- Z-axis Offset During Mapping: While creating the map, I observed an unexpected "jump" in the Z-axis, resulting in the map appearing to be generated above the robot's origin. After this sudden shift, the map creation stabilizes. I'm concerned this behavior may be affecting the AMCL localization.

4- Other factors: Could the slight 10-degree downward tilt of my lidar sensor be influencing this behavior?

Tutorial Visualization

My robot Visualization:

Here is a YouTube video demonstrating the problem. I would appreciate any guidance or suggestions for resolving this issue.