<!-- Copyright 2021 DeepMind Technologies Limited
     Licensed under the Apache License, Version 2.0 (the "License");
     you may not use this file except in compliance with the License.
     You may obtain a copy of the License at
         http://www.apache.org/licenses/LICENSE-2.0
     Unless required by applicable law or agreed to in writing, software
     distributed under the License is distributed on an "AS IS" BASIS,
     WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
     See the License for the specific language governing permissions and
     limitations under the License.
-->

<mujoco model="Humanoid body">
<!-- Degree of Freedom: 27
     Actuators: 21

     This simplified humanoid model, introduced in [1], is designed for bipedal locomotion
     behaviours. While several variants of it exist in the wild, this version is based on the model
     in the DeepMind Control Suite [2], which has fairly realistic actuator gains.
     [1] Synthesis and Stabilization of Complex Behaviors through Online Trajectory Optimization.
           https://doi.org/10.1109/IROS.2012.6386025
     [2] DeepMind Control Suite, Tassa et al. https://arxiv.org/abs/1801.00690
-->

  <asset>
    <texture type="skybox" builtin="gradient" rgb1=".3 .5 .7" rgb2="0 0 0" width="512" height="512"/>
    <texture name="body" type="cube" builtin="flat" mark="cross" width="127" height="1278"
             rgb1="0.8 0.6 0.4" rgb2="0.8 0.6 0.4" markrgb="1 1 1" random="0.01"/>
    <material name="body" texture="body" texuniform="true" rgba="0.8 0.6 .4 1"/>
    <texture name="grid" type="2d" builtin="checker" width="512" height="512" rgb1=".1 .2 .3" rgb2=".2 .3 .4"/>
    <material name="grid" texture="grid" texrepeat="1 1" texuniform="true" reflectance=".2"/>
  </asset>

  <default>
    <motor ctrlrange="-1 1" ctrllimited="true"/>
    <default class="body">
      <geom type="capsule" condim="1" friction=".7" solimp=".9 .99 .003" solref=".015 1" material="body"/>
      <joint type="hinge" damping=".2" stiffness="1" armature=".01" limited="true" solimplimit="0 .99 .01"/>
      <default class="big_joint">
        <joint damping="5" stiffness="10"/>
        <default class="big_stiff_joint">
          <joint stiffness="20"/>
        </default>
      </default>
    </default>
  </default>

  <visual>
    <map force="0.1" zfar="30"/>
    <rgba haze="0.15 0.25 0.35 1"/>
    <quality shadowsize="4096"/>
    <global offwidth="800" offheight="800"/>
  </visual>

  <worldbody>
    <body name="torso" pos="0 0 1.5" childclass="body">
      <camera name="back" pos="-3 0 1" xyaxes="0 -1 0 1 0 2" mode="trackcom"/>
      <camera name="side" pos="0 -3 1" xyaxes="1 0 0 0 1 2" mode="trackcom"/>
      <freejoint name="root"/>
      <geom name="torso" fromto="0 -.07 0 0 .07 0" size=".07"/>
      <geom name="upper_waist" fromto="-.01 -.06 -.12 -.01 .06 -.12" size=".06"/>
      <body name="head" pos="0 0 .19">
        <geom name="head" type="sphere" size=".09"/>
        <camera name="egocentric" pos=".09 0 0" xyaxes="0 -1 0 .1 0 1" fovy="80"/>
      </body>
      <body name="lower_waist" pos="-.01 0 -.26">
        <geom name="lower_waist" fromto="0 -.06 0 0 .06 0" size=".06"/>
        <joint name="abdomen_z" pos="0 0 .065" axis="0 0 1" range="-45 45" class="big_stiff_joint"/>
        <joint name="abdomen_y" pos="0 0 .065" axis="0 1 0" range="-75 30" class="big_joint"/>
        <body name="pelvis" pos="0 0 -.165">
          <joint name="abdomen_x" pos="0 0 .1" axis="1 0 0" range="-35 35" class="big_joint"/>
          <geom name="butt" fromto="-.02 -.07 0 -.02 .07 0" size=".09"/>
          <body name="right_thigh" pos="0 -.1 -.04">
            <joint name="right_hip_x" axis="1 0 0" range="-25 5" class="big_joint"/>
            <joint name="right_hip_z" axis="0 0 1" range="-60 35" class="big_joint"/>
            <joint name="right_hip_y" axis="0 1 0" range="-110 20" class="big_stiff_joint"/>
            <geom name="right_thigh" fromto="0 0 0 0 .01 -.34" size=".06"/>
            <body name="right_shin" pos="0 .01 -.403">
              <joint name="right_knee" pos="0 0 .02" axis="0 -1 0" range="-160 2"/>
              <geom name="right_shin" fromto="0 0 0 0 0 -.3"  size=".049"/>
              <body name="right_foot" pos="0 0 -.39">
                <joint name="right_ankle_y" pos="0 0 .08" axis="0 1 0" range="-50 50" stiffness="6"/>
                <joint name="right_ankle_x" pos="0 0 .04" axis="1 0 .5" range="-50 50" stiffness="3"/>
                <geom name="right_right_foot" fromto="-.07 -.02 0 .14 -.04 0" size=".027"/>
                <geom name="left_right_foot" fromto="-.07 0 0 .14  .02 0" size=".027"/>
              </body>
            </body>
          </body>
          <body name="left_thigh" pos="0 .1 -.04">
            <joint name="left_hip_x" axis="-1 0 0" range="-25 5" class="big_joint"/>
            <joint name="left_hip_z" axis="0 0 -1" range="-60 35" class="big_joint"/>
            <joint name="left_hip_y" axis="0 1 0" range="-110 20" class="big_stiff_joint"/>
            <geom name="left_thigh" fromto="0 0 0 0 -.01 -.34" size=".06"/>
            <body name="left_shin" pos="0 -.01 -.403">
              <joint name="left_knee" pos="0 0 .02" axis="0 -1 0" range="-160 2"/>
              <geom name="left_shin" fromto="0 0 0 0 0 -.3"  size=".049"/>
              <body name="left_foot" pos="0 0 -.39">
                <joint name="left_ankle_y" pos="0 0 .08" axis="0 1 0" range="-50 50" stiffness="6"/>
                <joint name="left_ankle_x" pos="0 0 .04" axis="1 0 .5" range="-50 50" stiffness="3"/>
                <geom name="left_left_foot" fromto="-.07 .02 0 .14 .04 0" size=".027"/>
                <geom name="right_left_foot" fromto="-.07 0 0 .14 -.02 0" size=".027"/>
              </body>
            </body>
          </body>
        </body>
      </body>
      <body name="right_upper_arm" pos="0 -.17 .06">
        <joint name="right_shoulder1" axis="2 1 1"  range="-85 60"/>
        <joint name="right_shoulder2" axis="0 -1 1" range="-85 60"/>
        <geom name="right_upper_arm" fromto="0 0 0 .16 -.16 -.16" size=".04 .16"/>
        <body name="right_lower_arm" pos=".18 -.18 -.18">
          <joint name="right_elbow" axis="0 -1 1" range="-90 50" stiffness="0"/>
          <geom name="right_lower_arm" fromto=".01 .01 .01 .17 .17 .17" size=".031"/>
          <body name="right_hand" pos=".18 .18 .18">
            <geom name="right_hand" type="sphere" size=".04" zaxis="1 1 1"/>
          </body>
        </body>
      </body>
      <body name="left_upper_arm" pos="0 .17 .06">
        <joint name="left_shoulder1" axis="2 -1 1" range="-60 85"/>
        <joint name="left_shoulder2" axis="0 1 1"  range="-60 85"/>
        <geom name="left_upper_arm" fromto="0 0 0 .16 .16 -.16" size=".04 .16"/>
        <body name="left_lower_arm" pos=".18 .18 -.18">
          <joint name="left_elbow" axis="0 -1 -1" range="-90 50" stiffness="0"/>
          <geom name="left_lower_arm" fromto=".01 -.01 .01 .17 -.17 .17" size=".031"/>
          <body name="left_hand" pos=".18 -.18 .18">
            <geom name="left_hand" type="sphere" size=".04" zaxis="1 -1 1"/>
          </body>
        </body>
      </body>
    </body>
  </worldbody>

  <actuator>
    <motor name="abdomen_y"       gear="40"  joint="abdomen_y"/>
    <motor name="abdomen_z"       gear="40"  joint="abdomen_z"/>
    <motor name="abdomen_x"       gear="40"  joint="abdomen_x"/>
    <motor name="right_hip_x"     gear="40"  joint="right_hip_x"/>
    <motor name="right_hip_z"     gear="40"  joint="right_hip_z"/>
    <motor name="right_hip_y"     gear="120" joint="right_hip_y"/>
    <motor name="right_knee"      gear="80"  joint="right_knee"/>
    <motor name="right_ankle_x"   gear="20"  joint="right_ankle_x"/>
    <motor name="right_ankle_y"   gear="20"  joint="right_ankle_y"/>
    <motor name="left_hip_x"      gear="40"  joint="left_hip_x"/>
    <motor name="left_hip_z"      gear="40"  joint="left_hip_z"/>
    <motor name="left_hip_y"      gear="120" joint="left_hip_y"/>
    <motor name="left_knee"       gear="80"  joint="left_knee"/>
    <motor name="left_ankle_x"    gear="20"  joint="left_ankle_x"/>
    <motor name="left_ankle_y"    gear="20"  joint="left_ankle_y"/>
    <motor name="right_shoulder1" gear="20"  joint="right_shoulder1"/>
    <motor name="right_shoulder2" gear="20"  joint="right_shoulder2"/>
    <motor name="right_elbow"     gear="40"  joint="right_elbow"/>
    <motor name="left_shoulder1"  gear="20"  joint="left_shoulder1"/>
    <motor name="left_shoulder2"  gear="20"  joint="left_shoulder2"/>
    <motor name="left_elbow"      gear="40"  joint="left_elbow"/>
  </actuator>
</mujoco>
