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import os | |
import numpy as np | |
from dm_control.rl import control | |
from dm_control.suite import common | |
from dm_control.suite import walker | |
from dm_control.utils import rewards | |
from dm_control.utils import io as resources | |
_TASKS_DIR = os.path.join(os.path.dirname(os.path.dirname(__file__)), 'custom_dmc_tasks') | |
_YOGA_STAND_HEIGHT = 1.0 # lower than stan height = 1.2 | |
_YOGA_LIE_DOWN_HEIGHT = 0.1 | |
_YOGA_LEGS_UP_HEIGHT = 1.1 | |
_YOGA_FEET_UP_HEIGHT = 0.5 | |
_YOGA_FEET_UP_LIE_DOWN_HEIGHT = 0.35 | |
_YOGA_KNEE_HEIGHT = 0.25 | |
_YOGA_KNEESTAND_HEIGHT = 0.75 | |
_YOGA_SITTING_HEIGHT = 0.55 | |
_YOGA_SITTING_LEGS_HEIGHT = 0.15 | |
# speed from: https://github.com/rll-research/url_benchmark/blob/710c3eb/custom_dmc_tasks/walker.py | |
_SPIN_SPEED = 5.0 | |
# | |
class WalkerYogaPoses: | |
""" | |
Joint positions for some yoga poses | |
""" | |
lie_back = [ -1.2 , 0. , -1.57, 0, 0. , 0.0, 0, -0., 0.0] | |
lie_front = [-1.2, -0, 1.57, 0, -0.2, 0, 0, -0.2, 0.] | |
legs_up = [ -1.24 , 0. , -1.57, 1.57, 0. , 0.0, 1.57, -0., 0.0] | |
kneel = [ -0.5 , 0. , 0, 0, -1.57, -0.8, 1.57, -1.57, 0.0] | |
side_angle = [ -0.3 , 0. , 0.9, 0, 0, -0.7, 1.87, -1.07, 0.0] | |
stand_up = [-0.15, 0., 0.34, 0.74, -1.34, -0., 1.1, -0.66, -0.1] | |
lean_back = [-0.27, 0., -0.45, 0.22, -1.5, 0.86, 0.6, -0.8, -0.4] | |
boat = [ -1.04 , 0. , -0.8, 1.6, 0. , 0.0, 1.6, -0., 0.0] | |
bridge = [-1.1, 0., -2.2, -0.3, -1.5, 0., -0.3, -0.8, -0.4] | |
head_stand = [-1, 0., -3, 0.6, -1, -0.3, 0.9, -0.5, 0.3] | |
one_foot = [-0.2, 0., 0, 0.7, -1.34, 0.5, 1.5, -0.6, 0.1] | |
arabesque = [-0.34, 0., 1.57, 1.57, 0, 0., 0, -0., 0.] | |
# new | |
high_kick = [-0.165, 3.3 , 5.55 , 1.35 ,-0, +0.5 , -0.7, 0. , 0.2,] | |
splits = [-0.7, 0., 0.5, -0.7, -1. , 0, 1.75, 0., -0.45 ] | |
def get_model_and_assets(): | |
"""Returns a tuple containing the model XML string and a dict of assets.""" | |
return resources.GetResource(os.path.join(_TASKS_DIR, 'walker.xml')), common.ASSETS | |
def walk_backwards(time_limit=walker._DEFAULT_TIME_LIMIT, random=None, environment_kwargs=None): | |
"""Returns the Walk Backwards task.""" | |
physics = walker.Physics.from_xml_string(*get_model_and_assets()) | |
task = BackwardsPlanarWalker(move_speed=walker._WALK_SPEED, random=random) | |
environment_kwargs = environment_kwargs or {} | |
return control.Environment( | |
physics, task, time_limit=time_limit, control_timestep=walker._CONTROL_TIMESTEP, | |
**environment_kwargs) | |
def run_backwards(time_limit=walker._DEFAULT_TIME_LIMIT, random=None, environment_kwargs=None): | |
"""Returns the Run Backwards task.""" | |
physics = walker.Physics.from_xml_string(*get_model_and_assets()) | |
task = BackwardsPlanarWalker(move_speed=walker._RUN_SPEED, random=random) | |
environment_kwargs = environment_kwargs or {} | |
return control.Environment( | |
physics, task, time_limit=time_limit, control_timestep=walker._CONTROL_TIMESTEP, | |
**environment_kwargs) | |
def arabesque(time_limit=walker._DEFAULT_TIME_LIMIT, random=None, environment_kwargs=None): | |
"""Returns the Arabesque task.""" | |
physics = walker.Physics.from_xml_string(*get_model_and_assets()) | |
task = YogaPlanarWalker(goal='arabesque', random=random) | |
environment_kwargs = environment_kwargs or {} | |
return control.Environment( | |
physics, task, time_limit=time_limit, control_timestep=walker._CONTROL_TIMESTEP, | |
**environment_kwargs) | |
def lying_down(time_limit=walker._DEFAULT_TIME_LIMIT, random=None, environment_kwargs=None): | |
"""Returns the Lie Down task.""" | |
physics = walker.Physics.from_xml_string(*get_model_and_assets()) | |
task = YogaPlanarWalker(goal='lying_down', random=random) | |
environment_kwargs = environment_kwargs or {} | |
return control.Environment( | |
physics, task, time_limit=time_limit, control_timestep=walker._CONTROL_TIMESTEP, | |
**environment_kwargs) | |
def legs_up(time_limit=walker._DEFAULT_TIME_LIMIT, random=None, environment_kwargs=None): | |
"""Returns the Legs Up task.""" | |
physics = walker.Physics.from_xml_string(*get_model_and_assets()) | |
task = YogaPlanarWalker(goal='legs_up', random=random) | |
environment_kwargs = environment_kwargs or {} | |
return control.Environment( | |
physics, task, time_limit=time_limit, control_timestep=walker._CONTROL_TIMESTEP, | |
**environment_kwargs) | |
def high_kick(time_limit=walker._DEFAULT_TIME_LIMIT, random=None, environment_kwargs=None): | |
"""Returns the High Kick task.""" | |
physics = walker.Physics.from_xml_string(*get_model_and_assets()) | |
task = YogaPlanarWalker(goal='high_kick', random=random) | |
environment_kwargs = environment_kwargs or {} | |
return control.Environment( | |
physics, task, time_limit=time_limit, control_timestep=walker._CONTROL_TIMESTEP, | |
**environment_kwargs) | |
def one_foot(time_limit=walker._DEFAULT_TIME_LIMIT, random=None, environment_kwargs=None): | |
"""Returns the High Kick task.""" | |
physics = walker.Physics.from_xml_string(*get_model_and_assets()) | |
task = YogaPlanarWalker(goal='one_foot', random=random) | |
environment_kwargs = environment_kwargs or {} | |
return control.Environment( | |
physics, task, time_limit=time_limit, control_timestep=walker._CONTROL_TIMESTEP, | |
**environment_kwargs) | |
def lunge_pose(time_limit=walker._DEFAULT_TIME_LIMIT, random=None, environment_kwargs=None): | |
"""Returns the High Kick task.""" | |
physics = walker.Physics.from_xml_string(*get_model_and_assets()) | |
task = YogaPlanarWalker(goal='lunge_pose', random=random) | |
environment_kwargs = environment_kwargs or {} | |
return control.Environment( | |
physics, task, time_limit=time_limit, control_timestep=walker._CONTROL_TIMESTEP, | |
**environment_kwargs) | |
def sit_knees(time_limit=walker._DEFAULT_TIME_LIMIT, random=None, environment_kwargs=None): | |
"""Returns the High Kick task.""" | |
physics = walker.Physics.from_xml_string(*get_model_and_assets()) | |
task = YogaPlanarWalker(goal='sit_knees', random=random) | |
environment_kwargs = environment_kwargs or {} | |
return control.Environment( | |
physics, task, time_limit=time_limit, control_timestep=walker._CONTROL_TIMESTEP, | |
**environment_kwargs) | |
def headstand(time_limit=walker._DEFAULT_TIME_LIMIT, random=None, environment_kwargs=None): | |
"""Returns the Headstand task.""" | |
physics = walker.Physics.from_xml_string(*get_model_and_assets()) | |
task = YogaPlanarWalker(goal='flip', move_speed=0, random=random) | |
environment_kwargs = environment_kwargs or {} | |
return control.Environment( | |
physics, task, time_limit=time_limit, control_timestep=walker._CONTROL_TIMESTEP, | |
**environment_kwargs) | |
def urlb_flip(time_limit=walker._DEFAULT_TIME_LIMIT, random=None, environment_kwargs=None): | |
"""Returns the Flip task.""" | |
physics = walker.Physics.from_xml_string(*get_model_and_assets()) | |
task = YogaPlanarWalker(goal='urlb_flip', move_speed=_SPIN_SPEED, random=random) | |
environment_kwargs = environment_kwargs or {} | |
return control.Environment( | |
physics, task, time_limit=time_limit, control_timestep=walker._CONTROL_TIMESTEP, | |
**environment_kwargs) | |
def flipping(time_limit=walker._DEFAULT_TIME_LIMIT, random=None, environment_kwargs=None): | |
"""Returns the flipping task.""" | |
physics = walker.Physics.from_xml_string(*get_model_and_assets()) | |
task = YogaPlanarWalker(goal='flipping', move_speed=2* walker._RUN_SPEED, random=random) | |
environment_kwargs = environment_kwargs or {} | |
return control.Environment( | |
physics, task, time_limit=time_limit, control_timestep=walker._CONTROL_TIMESTEP, | |
**environment_kwargs) | |
def flip(time_limit=walker._DEFAULT_TIME_LIMIT, random=None, environment_kwargs=None): | |
"""Returns the Flip task.""" | |
physics = walker.Physics.from_xml_string(*get_model_and_assets()) | |
task = YogaPlanarWalker(goal='flip', move_speed=2* walker._RUN_SPEED, random=random) | |
environment_kwargs = environment_kwargs or {} | |
return control.Environment( | |
physics, task, time_limit=time_limit, control_timestep=walker._CONTROL_TIMESTEP, | |
**environment_kwargs) | |
def backflip(time_limit=walker._DEFAULT_TIME_LIMIT, random=None, environment_kwargs=None): | |
"""Returns the Backflip task.""" | |
physics = walker.Physics.from_xml_string(*get_model_and_assets()) | |
task = YogaPlanarWalker(goal='flip', move_speed=-2 * walker._RUN_SPEED, random=random) | |
environment_kwargs = environment_kwargs or {} | |
return control.Environment( | |
physics, task, time_limit=time_limit, control_timestep=walker._CONTROL_TIMESTEP, | |
**environment_kwargs) | |
class BackwardsPlanarWalker(walker.PlanarWalker): | |
"""Backwards PlanarWalker task.""" | |
def __init__(self, move_speed, random=None): | |
super().__init__(move_speed, random) | |
def get_reward(self, physics): | |
standing = rewards.tolerance(physics.torso_height(), | |
bounds=(_YOGA_STAND_HEIGHT, float('inf')), | |
margin=_YOGA_STAND_HEIGHT/2) | |
upright = (1 + physics.torso_upright()) / 2 | |
stand_reward = (3*standing + upright) / 4 | |
if self._move_speed == 0: | |
return stand_reward | |
else: | |
move_reward = rewards.tolerance(physics.horizontal_velocity(), | |
bounds=(-float('inf'), -self._move_speed), | |
margin=self._move_speed/2, | |
value_at_margin=0.5, | |
sigmoid='linear') | |
return stand_reward * (5*move_reward + 1) / 6 | |
class YogaPlanarWalker(walker.PlanarWalker): | |
"""Yoga PlanarWalker tasks.""" | |
def __init__(self, goal='arabesque', move_speed=0, random=None): | |
super().__init__(0, random) | |
self._goal = goal | |
self._move_speed = move_speed | |
def _arabesque_reward(self, physics): | |
# standing horizontal | |
# one foot up, same height as torso | |
# one foot down | |
standing = rewards.tolerance(physics.torso_height(), | |
bounds=(_YOGA_STAND_HEIGHT, float('inf')), | |
margin=_YOGA_STAND_HEIGHT/2) | |
left_foot_height = physics.named.data.xpos['left_foot', 'z'] | |
right_foot_height = physics.named.data.xpos['right_foot', 'z'] | |
max_foot = 'right_foot' if right_foot_height > left_foot_height else 'left_foot' | |
min_foot = 'right_foot' if right_foot_height <= left_foot_height else 'left_foot' | |
min_foot_height = physics.named.data.xpos[min_foot, 'z'] | |
max_foot_height = physics.named.data.xpos[max_foot, 'z'] | |
min_foot_down = rewards.tolerance(min_foot_height, | |
bounds=(-float('inf'), _YOGA_LIE_DOWN_HEIGHT), | |
margin=_YOGA_LIE_DOWN_HEIGHT*1.5) | |
max_foot_up = rewards.tolerance(max_foot_height, | |
bounds=(_YOGA_STAND_HEIGHT, float('inf')), | |
margin=_YOGA_STAND_HEIGHT/2) | |
min_foot_x = physics.named.data.xpos[min_foot, 'x'] | |
max_foot_x = physics.named.data.xpos[max_foot, 'x'] | |
correct_foot_pose = 0.1 if max_foot_x > min_foot_x else 1.0 | |
feet_pose = (min_foot_down + max_foot_up * 2) / 3 | |
return standing * feet_pose * correct_foot_pose | |
def _lying_down_reward(self, physics): | |
# torso down and horizontal | |
# thigh and feet down | |
torso_down = rewards.tolerance(physics.torso_height(), | |
bounds=(-float('inf'), _YOGA_LIE_DOWN_HEIGHT), | |
margin=_YOGA_LIE_DOWN_HEIGHT*1.5) | |
horizontal = 1 - abs(physics.torso_upright()) | |
thigh_height = (physics.named.data.xpos['left_thigh', 'z'] + physics.named.data.xpos['right_thigh', 'z']) / 2 | |
thigh_down = rewards.tolerance(thigh_height, | |
bounds=(-float('inf'), _YOGA_LIE_DOWN_HEIGHT), | |
margin=_YOGA_LIE_DOWN_HEIGHT*1.5) | |
leg_height = (physics.named.data.xpos['left_leg', 'z'] + physics.named.data.xpos['right_leg', 'z']) / 2 | |
leg_down = rewards.tolerance(leg_height, | |
bounds=(-float('inf'), _YOGA_LIE_DOWN_HEIGHT), | |
margin=_YOGA_LIE_DOWN_HEIGHT*1.5) | |
feet_height = (physics.named.data.xpos['left_foot', 'z'] + physics.named.data.xpos['right_foot', 'z']) / 2 | |
feet_down = rewards.tolerance(feet_height, | |
bounds=(-float('inf'), _YOGA_LIE_DOWN_HEIGHT), | |
margin=_YOGA_LIE_DOWN_HEIGHT*1.5) | |
return (3*torso_down + horizontal + thigh_down + feet_down + leg_down) / 7 | |
def _legs_up_reward(self, physics): | |
# torso down and horizontal | |
# legs up with thigh down | |
torso_down = rewards.tolerance(physics.torso_height(), | |
bounds=(-float('inf'), _YOGA_LIE_DOWN_HEIGHT), | |
margin=_YOGA_LIE_DOWN_HEIGHT*1.5) | |
horizontal = 1 - abs(physics.torso_upright()) | |
torso_down = (3*torso_down +horizontal) / 4 | |
feet_height = (physics.named.data.xpos['left_foot', 'z'] + physics.named.data.xpos['right_foot', 'z']) / 2 | |
feet_up = rewards.tolerance(feet_height, | |
bounds=(_YOGA_FEET_UP_LIE_DOWN_HEIGHT, float('inf')), | |
margin=_YOGA_FEET_UP_LIE_DOWN_HEIGHT/2) | |
return torso_down * feet_up | |
def _high_kick_reward(self, physics): | |
# torso up, but lower than standing | |
# foot up, higher than torso | |
# foot down | |
standing = rewards.tolerance(physics.torso_height(), | |
bounds=(_YOGA_STAND_HEIGHT, float('inf')), | |
margin=_YOGA_STAND_HEIGHT/2) | |
left_foot_height = physics.named.data.xpos['left_foot', 'z'] | |
right_foot_height = physics.named.data.xpos['right_foot', 'z'] | |
min_foot_height = min(left_foot_height, right_foot_height) | |
max_foot_height = max(left_foot_height, right_foot_height) | |
min_foot_down = rewards.tolerance(min_foot_height, | |
bounds=(-float('inf'), _YOGA_LIE_DOWN_HEIGHT), | |
margin=_YOGA_LIE_DOWN_HEIGHT*1.5) | |
max_foot_up = rewards.tolerance(max_foot_height, | |
bounds=(walker._STAND_HEIGHT, float('inf')), | |
margin=walker._STAND_HEIGHT/2) | |
feet_pose = (3 * max_foot_up + min_foot_down) / 4 | |
return standing * feet_pose | |
def _one_foot_reward(self, physics): | |
# torso up, standing | |
# foot up higher than foot down | |
standing = rewards.tolerance(physics.torso_height(), | |
bounds=(_YOGA_STAND_HEIGHT, float('inf')), | |
margin=_YOGA_STAND_HEIGHT/2) | |
left_foot_height = physics.named.data.xpos['left_foot', 'z'] | |
right_foot_height = physics.named.data.xpos['right_foot', 'z'] | |
min_foot_height = min(left_foot_height, right_foot_height) | |
max_foot_height = max(left_foot_height, right_foot_height) | |
min_foot_down = rewards.tolerance(min_foot_height, | |
bounds=(-float('inf'), _YOGA_LIE_DOWN_HEIGHT), | |
margin=_YOGA_LIE_DOWN_HEIGHT*1.5) | |
max_foot_up = rewards.tolerance(max_foot_height, | |
bounds=(_YOGA_FEET_UP_HEIGHT, float('inf')), | |
margin=_YOGA_FEET_UP_HEIGHT/2) | |
return standing * max_foot_up * min_foot_down | |
def _lunge_pose_reward(self, physics): | |
# torso up, standing, but lower | |
# leg up higher than leg down | |
# horiontal thigh and leg | |
standing = rewards.tolerance(physics.torso_height(), | |
bounds=(_YOGA_KNEESTAND_HEIGHT, float('inf')), | |
margin=_YOGA_KNEESTAND_HEIGHT/2) | |
upright = (1 + physics.torso_upright()) / 2 | |
torso = (3*standing + upright) / 4 | |
left_leg_height = physics.named.data.xpos['left_leg', 'z'] | |
right_leg_height = physics.named.data.xpos['right_leg', 'z'] | |
min_leg_height = min(left_leg_height, right_leg_height) | |
max_leg_height = max(left_leg_height, right_leg_height) | |
min_leg_down = rewards.tolerance(min_leg_height, | |
bounds=(-float('inf'), _YOGA_LIE_DOWN_HEIGHT), | |
margin=_YOGA_LIE_DOWN_HEIGHT*1.5) | |
max_leg_up = rewards.tolerance(max_leg_height, | |
bounds=(_YOGA_KNEE_HEIGHT, float('inf')), | |
margin=_YOGA_KNEE_HEIGHT / 2) | |
max_thigh = 'left_thigh' if max_leg_height == left_leg_height else 'right_thigh' | |
min_leg = 'left_leg' if min_leg_height == left_leg_height else 'right_leg' | |
max_thigh_horiz = 1 - abs(physics.named.data.xmat[max_thigh, 'zz']) | |
min_leg_horiz = 1 - abs(physics.named.data.xmat[min_leg, 'zz']) | |
legs = (min_leg_down + max_leg_up + max_thigh_horiz + min_leg_horiz) / 4 | |
return torso * legs | |
def _sit_knees_reward(self, physics): | |
# torso up, standing, but lower | |
# foot up higher than foot down | |
standing = rewards.tolerance(physics.torso_height(), | |
bounds=(_YOGA_SITTING_HEIGHT, float('inf')), | |
margin=_YOGA_SITTING_HEIGHT/2) | |
upright = (1 + physics.torso_upright()) / 2 | |
torso_up = (3*standing + upright) / 4 | |
legs_height = (physics.named.data.xpos['left_leg', 'z'] + physics.named.data.xpos['right_leg', 'z']) / 2 | |
legs_down = rewards.tolerance(legs_height, | |
bounds=(-float('inf'), _YOGA_SITTING_LEGS_HEIGHT), | |
margin=_YOGA_SITTING_LEGS_HEIGHT*1.5) | |
feet_height = (physics.named.data.xpos['left_foot', 'z'] + physics.named.data.xpos['right_foot', 'z']) / 2 | |
feet_down = rewards.tolerance(feet_height, | |
bounds=(-float('inf'), _YOGA_LIE_DOWN_HEIGHT), | |
margin=_YOGA_LIE_DOWN_HEIGHT*1.5) | |
l_thigh_foot_distance = max(0.1, abs(physics.named.data.xpos['left_foot', 'x'] - physics.named.data.xpos['left_thigh', 'x'])) - 0.1 | |
r_thigh_foot_distance = max(0.1, abs(physics.named.data.xpos['right_foot', 'x'] - physics.named.data.xpos['right_thigh', 'x'])) - 0.1 | |
close = np.exp(-(l_thigh_foot_distance + r_thigh_foot_distance)/2) | |
legs = (3 * legs_down + feet_down) / 4 | |
return torso_up * legs * close | |
def _urlb_flip_reward(self, physics): | |
standing = rewards.tolerance(physics.torso_height(), | |
bounds=(walker._STAND_HEIGHT, float('inf')), | |
margin=walker._STAND_HEIGHT / 2) | |
upright = (1 + physics.torso_upright()) / 2 | |
stand_reward = (3 * standing + upright) / 4 | |
move_reward = rewards.tolerance(physics.named.data.subtree_angmom['torso'][1], # physics.angmomentum(), | |
bounds=(_SPIN_SPEED, float('inf')), | |
margin=_SPIN_SPEED, | |
value_at_margin=0, | |
sigmoid='linear') | |
return stand_reward * (5 * move_reward + 1) / 6 | |
def _flip_reward(self, physics): | |
thigh_height = (physics.named.data.xpos['left_thigh', 'z'] + physics.named.data.xpos['right_thigh', 'z']) / 2 | |
thigh_up = rewards.tolerance(thigh_height, | |
bounds=(_YOGA_STAND_HEIGHT, float('inf')), | |
margin=_YOGA_STAND_HEIGHT/2) | |
feet_height = (physics.named.data.xpos['left_foot', 'z'] + physics.named.data.xpos['right_foot', 'z']) / 2 | |
legs_up = rewards.tolerance(feet_height, | |
bounds=(_YOGA_LEGS_UP_HEIGHT, float('inf')), | |
margin=_YOGA_LEGS_UP_HEIGHT/2) | |
upside_down_reward = (3*legs_up + 2*thigh_up) / 5 | |
if self._move_speed == 0: | |
return upside_down_reward | |
move_reward = rewards.tolerance(physics.named.data.subtree_angmom['torso'][1], # physics.angmomentum(), | |
bounds=(self._move_speed, float('inf')) if self._move_speed > 0 else (-float('inf'), self._move_speed), | |
margin=abs(self._move_speed)/2, | |
value_at_margin=0.5, | |
sigmoid='linear') | |
return upside_down_reward * (5*move_reward + 1) / 6 | |
def get_reward(self, physics): | |
if self._goal == 'arabesque': | |
return self._arabesque_reward(physics) | |
elif self._goal == 'lying_down': | |
return self._lying_down_reward(physics) | |
elif self._goal == 'legs_up': | |
return self._legs_up_reward(physics) | |
elif self._goal == 'flip': | |
return self._flip_reward(physics) | |
elif self._goal == 'flipping': | |
self._move_speed = abs(self._move_speed) | |
pos_rew = self._flip_reward(physics) | |
self._move_speed = -abs(self._move_speed) | |
neg_rew = self._flip_reward(physics) | |
return max(pos_rew, neg_rew) | |
elif self._goal == 'high_kick': | |
return self._high_kick_reward(physics) | |
elif self._goal == 'one_foot': | |
return self._one_foot_reward(physics) | |
elif self._goal == 'lunge_pose': | |
return self._lunge_pose_reward(physics) | |
elif self._goal == 'sit_knees': | |
return self._sit_knees_reward(physics) | |
elif self._goal == 'urlb_flip': | |
return self._urlb_flip_reward(physics) | |
else: | |
raise NotImplementedError(f'Goal {self._goal} is not implemented.') | |
if __name__ == '__main__': | |
from dm_control import viewer | |
import numpy as np | |
env = sit_knees() | |
env.task.visualize_reward = True | |
action_spec = env.action_spec() | |
def zero_policy(time_step): | |
print(time_step.reward) | |
return np.zeros(action_spec.shape) | |
viewer.launch(env, policy=zero_policy) | |
# obs = env.reset() | |
# next_obs, reward, done, info = env.step(np.zeros(6)) |