bullet3

<mujoco model="humanoid">
    <compiler angle="degree" inertiafromgeom="true"/>
    <default>
        <joint armature="1" damping="1" limited="true"/>
        <geom conaffinity="1" condim="1" contype="1" margin="0.001" material="geom" rgba="0.8 0.6 .4 1"/>
        <motor ctrllimited="true" ctrlrange="-.4 .4"/>
    </default>
    <option integrator="RK4" iterations="50" solver="PGS" timestep="0.003">
        <!-- <flags solverstat="enable" energy="enable"/>-->
    </option>
    <size nkey="5" nuser_geom="1"/>
    <visual>
        <map fogend="5" fogstart="3"/>
    </visual>
    <asset>
        <texture builtin="gradient" height="100" rgb1=".4 .5 .6" rgb2="0 0 0" type="skybox" width="100"/>
        <!-- <texture builtin="gradient" height="100" rgb1="1 1 1" rgb2="0 0 0" type="skybox" width="100"/>-->
        <texture builtin="flat" height="1278" mark="cross" markrgb="1 1 1" name="texgeom" random="0.01" rgb1="0.8 0.6 0.4" rgb2="0.8 0.6 0.4" type="cube" width="127"/>
        <texture builtin="checker" height="100" name="texplane" rgb1="0 0 0" rgb2="0.8 0.8 0.8" type="2d" width="100"/>
        <material name="MatPlane" reflectance="0.5" shininess="1" specular="1" texrepeat="60 60" texture="texplane"/>
        <material name="geom" texture="texgeom" texuniform="true"/>
    </asset>
    <worldbody>
        <!-- light cutoff="100" diffuse="1 1 1" dir="-0 0 -1.3" directional="true" exponent="1" pos="0 0 1.3" specular=".1 .1 .1"/-->
        <geom condim="3" friction="1 .1 .1" material="MatPlane" name="floor" pos="0 0 0" rgba="0.8 0.9 0.8 1" size="20 20 0.125" type="plane"/>
       
    </worldbody>
    <tendon>
        <fixed name="left_hipknee">
            <joint coef="-1" joint="left_hip_y"/>
            <joint coef="1" joint="left_knee"/>
        </fixed>
        <fixed name="right_hipknee">
            <joint coef="-1" joint="right_hip_y"/>
            <joint coef="1" joint="right_knee"/>
        </fixed>
    </tendon>
    <actuator><!-- this section is not supported, same constants in code -->
        <motor gear="100" joint="abdomen_y" name="abdomen_y"/>
        <motor gear="100" joint="abdomen_z" name="abdomen_z"/>
        <motor gear="100" joint="abdomen_x" name="abdomen_x"/>
        <motor gear="100" joint="right_hip_x" name="right_hip_x"/>
        <motor gear="100" joint="right_hip_z" name="right_hip_z"/>
        <motor gear="300" joint="right_hip_y" name="right_hip_y"/>
        <motor gear="200" joint="right_knee" name="right_knee"/>
        <motor gear="100" joint="left_hip_x" name="left_hip_x"/>
        <motor gear="100" joint="left_hip_z" name="left_hip_z"/>
        <motor gear="300" joint="left_hip_y" name="left_hip_y"/>
        <motor gear="200" joint="left_knee" name="left_knee"/>
        <motor gear="25" joint="right_shoulder1" name="right_shoulder1"/>
        <motor gear="25" joint="right_shoulder2" name="right_shoulder2"/>
        <motor gear="25" joint="right_elbow" name="right_elbow"/>
        <motor gear="25" joint="left_shoulder1" name="left_shoulder1"/>
        <motor gear="25" joint="left_shoulder2" name="left_shoulder2"/>
        <motor gear="25" joint="left_elbow" name="left_elbow"/>
    </actuator>
</mujoco>