AMCL randomly loses localisation.

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Hi,

I am using the `AMCL package with the following configuration:

<node pkg="amcl" type="amcl" name="amcl" clear_params="true">
    <param name="use_map_topic" value="$(arg use_map_topic)"/>

    <param name="odom_model_type" value="diff-corrected"/>
    <param name="odom_alpha5" value="0.0"/>
    <param name="gui_publish_rate" value="10.0"/>

    <param name="laser_max_beams" value="30"/>

    <param name="laser_max_range" value="-1.0"/> 
    <param name="laser_min_range" value="-1.0"/> 
    <param name="min_particles" value="500"/>

   <param name="max_particles" value="5000"/>
    <param name="kld_err" value="0.01"/> <!-- 0.05-->
    <param name="kld_z" value="0.99"/>
    <param name="odom_alpha1" value="4.0"/> <!-- 0.2-->
    <param name="odom_alpha2" value="0.9"/> <!-- 0.2-->

    <param name="odom_alpha3" value="0.2"/> <!-- 0.8 --> 
    <param name="odom_alpha4" value="0.2"/> <!-- 0.2-->
    <param name="laser_z_hit" value="0.5"/>
    <param name="laser_z_short" value="0.0"/>
    <param name="laser_z_max" value="0.0"/>
    <param name="laser_z_rand" value="0.5"/>
    <param name="laser_sigma_hit" value="0.2"/>
    <param name="laser_lambda_short" value="0.1"/>
    <param name="laser_model_type" value="likelihood_field"/>

    <param name="laser_likelihood_max_dist" value="2.0"/>
    <param name="update_min_d" value="-0.2"/> <!-- 0.25 -->
    <param name="update_min_a" value="-0.5"/> <!-- 0.2 -->
    <param name="odom_frame_id" value="odom"/>
    <param name="resample_interval" value="1"/>

    <param name="transform_tolerance" value="0.3"/> <!-- 1.0 -->
    <param name="recovery_alpha_slow" value="0.0"/>
    <param name="recovery_alpha_fast" value="0.0"/>

The good thing is when the laser points matches exactly the map then the localisation is perfect, however when the laser points does not match exactly the map (even slight difference) the AMCL tries correcting the robot's position on the map but it sets the robot in a completely wrong position.

I think it is something about the AMCL configuration but I do not know exactly which parameter.