xacro macros model not showing up in rviz(noetic)

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hi, I am trying to visualize xacro macros model on rviz which works fine in gazebo but i have few issues while visualizing it in rviz. in gazebo i am able to visualize the links, collision and inertia are properly configured but when i launch rviz i get this warning

    Unable to parse component [${base_length}] to a double (while parsing a vector value)
    [ERROR] [1623216223.772835121, 69.582000000]: Could not parse visual element for Link [base_link]

i tried rosparam load <myxacro.urdf.xacro> robot_description and the same error. i followed the solution in this thread but no luck.

and i also get robotmodel error.

    Parameter [robot_description] does not exist, and was not found by searchParam()

i tried running export LC_NUMERIC="en_US.UTF-8" before rviz but does not solve it.

my xacro files

inertials.xacro

<?xml version="1.0" ?>
<!--  xacro macros for inertials.

    Define xacro macros for math constants and inertials:

    - solid cuboid
    - solid cylinder
    - null (a placeholder inertial for logical link elements)
 -->
<robot name="inertials" xmlns:xacro="http://wiki.ros.org/xacro">

    <!-- Math constants -->
    <xacro:property name="math_pi"        value="3.141592653589793" />
    <xacro:property name="math_pi_over_2" value="1.5707963267948966" />
    <xacro:property name="math_pi_over_4" value="0.785398163397448" />

    <!-- Inertial for solid cuboid with dimensions x y z  -->
    <xacro:macro name="solid_cuboid_inertial" params="rpy xyz mass x y z">
        <inertial>
            <origin rpy="${rpy}" xyz="${xyz}"/>
            <mass value="${mass}" />
            <inertia
                ixx="${mass * (y * y + z * z) / 12.0}" ixy="0.0" ixz="0.0"
                iyy="${mass * (x * x + z * z) / 12.0}" iyz="0.0"
                izz="${mass * (x * x + y * y) / 12.0}" />
        </inertial>
    </xacro:macro>
    <solid_cuboid_inertial/>

    <!-- Inertial for solid cylinder with radius and length aligned to z-axis  -->
    <xacro:macro name="solid_cylinder_inertial" params="rpy xyz mass radius length">
        <inertial>
            <origin rpy="${rpy}" xyz="${xyz}"/>
            <mass value="${mass}" />
            <inertia
                ixx="${mass * (3.0 * radius * radius + length * length) / 12.0}" ixy="0.0" ixz="0.0"
                iyy="${mass * (3.0 * radius * radius + length * length) / 12.0}" iyz="0.0"
                izz="${mass * (radius * radius) / 2.0}" />
        </inertial>
    </xacro:macro>
    <solid_cylinder_inertial/>

    <!-- A null inertial - used in placeholder links to esure the model will work in Gazebo -->
    <xacro:macro name="null_inertial">
        <inertial>
            <mass value="0.001"/>
            <inertia ixx="0.001" ixy="0" ixz="0" iyy="0.001" iyz="0" izz="0.001"/>
        </inertial>
    </xacro:macro>
    <null_inertial/>

</robot>

materials.xacro

<?xml version="1.0" ?>
<!--  xacro macros for robot materials.
 -->
<robot name="materials" xmlns:xacro="http://wiki.ros.org/xacro">
   <material name="red">
        <color rgba="0.8 0 0 1"/>
    </material>

    <material name="green">
        <color rgba="0 0.8 0 1"/>
    </material>

    <material name="blue">
        <color rgba="0 0 0.8 1"/>
    </material>

    <material name="orange">
        <color rgba="0.8 0.25 0 1"/>
    </material>

wheel.xacro

< ...