PWM / PWM_code /policy_rl /act /ee_sim_env.py

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import numpy as np
import collections
import os

from constants import DT, XML_DIR, START_ARM_POSE
from constants import PUPPET_GRIPPER_POSITION_CLOSE
from constants import PUPPET_GRIPPER_POSITION_UNNORMALIZE_FN
from constants import PUPPET_GRIPPER_POSITION_NORMALIZE_FN
from constants import PUPPET_GRIPPER_VELOCITY_NORMALIZE_FN

from utils import sample_box_pose, sample_insertion_pose
from dm_control import mujoco
from dm_control.rl import control
from dm_control.suite import base

import IPython
e = IPython.embed


def make_ee_sim_env(task_name):
    """
    Environment for simulated robot bi-manual manipulation, with end-effector control.
    Action space:      [left_arm_pose (7),             # position and quaternion for end effector
                        left_gripper_positions (1),    # normalized gripper position (0: close, 1: open)
                        right_arm_pose (7),            # position and quaternion for end effector
                        right_gripper_positions (1),]  # normalized gripper position (0: close, 1: open)
    Observation space: {"qpos": Concat[ left_arm_qpos (6),         # absolute joint position
                                        left_gripper_position (1),  # normalized gripper position (0: close, 1: open)
                                        right_arm_qpos (6),         # absolute joint position
                                        right_gripper_qpos (1)]     # normalized gripper position (0: close, 1: open)
                        "qvel": Concat[ left_arm_qvel (6),         # absolute joint velocity (rad)
                                        left_gripper_velocity (1),  # normalized gripper velocity (pos: opening, neg: closing)
                                        right_arm_qvel (6),         # absolute joint velocity (rad)
                                        right_gripper_qvel (1)]     # normalized gripper velocity (pos: opening, neg: closing)
                        "images": {"main": (480x640x3)}        # h, w, c, dtype='uint8'
    """
    if 'sim_transfer_cube' in task_name:
        xml_path = os.path.join(XML_DIR, f'bimanual_viperx_ee_transfer_cube.xml')
        physics = mujoco.Physics.from_xml_path(xml_path)
        task = TransferCubeEETask(random=False)
        env = control.Environment(physics, task, time_limit=20, control_timestep=DT,
                                  n_sub_steps=None, flat_observation=False)
    elif 'sim_insertion' in task_name:
        xml_path = os.path.join(XML_DIR, f'bimanual_viperx_ee_insertion.xml')
        physics = mujoco.Physics.from_xml_path(xml_path)
        task = InsertionEETask(random=False)
        env = control.Environment(physics, task, time_limit=20, control_timestep=DT,
                                  n_sub_steps=None, flat_observation=False)
    else:
        raise NotImplementedError
    return env

class BimanualViperXEETask(base.Task):
    def __init__(self, random=None):
        super().__init__(random=random)

    def before_step(self, action, physics):
        a_len = len(action) // 2
        action_left = action[:a_len]
        action_right = action[a_len:]

        # set mocap position and quat
        # left
        np.copyto(physics.data.mocap_pos[0], action_left[:3])
        np.copyto(physics.data.mocap_quat[0], action_left[3:7])
        # right
        np.copyto(physics.data.mocap_pos[1], action_right[:3])
        np.copyto(physics.data.mocap_quat[1], action_right[3:7])

        # set gripper
        g_left_ctrl = PUPPET_GRIPPER_POSITION_UNNORMALIZE_FN(action_left[7])
        g_right_ctrl = PUPPET_GRIPPER_POSITION_UNNORMALIZE_FN(action_right[7])
        np.copyto(physics.data.ctrl, np.array([g_left_ctrl, -g_left_ctrl, g_right_ctrl, -g_right_ctrl]))

    def initialize_robots(self, physics):
        # reset joint position
        physics.named.data.qpos[:16] = START_ARM_POSE

        # reset mocap to align with end effector
        # to obtain these numbers:
        # (1) make an ee_sim env and reset to the same start_pose
        # (2) get env._physics.named.data.xpos['vx300s_left/gripper_link']
        #     get env._physics.named.data.xquat['vx300s_left/gripper_link']
        #     repeat the same for right side
        np.copyto(physics.data.mocap_pos[0], [-0.31718881, 0.5, 0.29525084])
        np.copyto(physics.data.mocap_quat[0], [1, 0, 0, 0])
        # right
        np.copyto(physics.data.mocap_pos[1], np.array([0.31718881, 0.49999888, 0.29525084]))
        np.copyto(physics.data.mocap_quat[1],  [1, 0, 0, 0])

        # reset gripper control
        close_gripper_control = np.array([
            PUPPET_GRIPPER_POSITION_CLOSE,
            -PUPPET_GRIPPER_POSITION_CLOSE,
            PUPPET_GRIPPER_POSITION_CLOSE,
            -PUPPET_GRIPPER_POSITION_CLOSE,
        ])
        np.copyto(physics.data.ctrl, close_gripper_control)

    def initialize_episode(self, physics):
        """Sets the state of the environment at the start of each episode."""
        super().initialize_episode(physics)

    @staticmethod
    def get_qpos(physics):
        qpos_raw = physics.data.qpos.copy()
        left_qpos_raw = qpos_raw[:8]
        right_qpos_raw = qpos_raw[8:16]
        left_arm_qpos = left_qpos_raw[:6]
        right_arm_qpos = right_qpos_raw[:6]
        left_gripper_qpos = [PUPPET_GRIPPER_POSITION_NORMALIZE_FN(left_qpos_raw[6])]
        right_gripper_qpos = [PUPPET_GRIPPER_POSITION_NORMALIZE_FN(right_qpos_raw[6])]
        return np.concatenate([left_arm_qpos, left_gripper_qpos, right_arm_qpos, right_gripper_qpos])

    @staticmethod
    def get_qvel(physics):
        qvel_raw = physics.data.qvel.copy()
        left_qvel_raw = qvel_raw[:8]
        right_qvel_raw = qvel_raw[8:16]
        left_arm_qvel = left_qvel_raw[:6]
        right_arm_qvel = right_qvel_raw[:6]
        left_gripper_qvel = [PUPPET_GRIPPER_VELOCITY_NORMALIZE_FN(left_qvel_raw[6])]
        right_gripper_qvel = [PUPPET_GRIPPER_VELOCITY_NORMALIZE_FN(right_qvel_raw[6])]
        return np.concatenate([left_arm_qvel, left_gripper_qvel, right_arm_qvel, right_gripper_qvel])

    @staticmethod
    def get_env_state(physics):
        raise NotImplementedError

    def get_observation(self, physics):
        # note: it is important to do .copy()
        obs = collections.OrderedDict()
        obs['qpos'] = self.get_qpos(physics)
        obs['qvel'] = self.get_qvel(physics)
        obs['env_state'] = self.get_env_state(physics)
        obs['images'] = dict()
        obs['images']['top'] = physics.render(height=480, width=640, camera_id='top')
        obs['images']['angle'] = physics.render(height=480, width=640, camera_id='angle')
        obs['images']['vis'] = physics.render(height=480, width=640, camera_id='front_close')
        # used in scripted policy to obtain starting pose
        obs['mocap_pose_left'] = np.concatenate([physics.data.mocap_pos[0], physics.data.mocap_quat[0]]).copy()
        obs['mocap_pose_right'] = np.concatenate([physics.data.mocap_pos[1], physics.data.mocap_quat[1]]).copy()

        # used when replaying joint trajectory
        obs['gripper_ctrl'] = physics.data.ctrl.copy()
        return obs

    def get_reward(self, physics):
        raise NotImplementedError


class TransferCubeEETask(BimanualViperXEETask):
    def __init__(self, random=None):
        super().__init__(random=random)
        self.max_reward = 4

    def initialize_episode(self, physics):
        """Sets the state of the environment at the start of each episode."""
        self.initialize_robots(physics)
        # randomize box position
        cube_pose = sample_box_pose()
        box_start_idx = physics.model.name2id('red_box_joint', 'joint')
        np.copyto(physics.data.qpos[box_start_idx : box_start_idx + 7], cube_pose)
        # print(f"randomized cube position to {cube_position}")

        super().initialize_episode(physics)

    @staticmethod
    def get_env_state(physics):
        env_state = physics.data.qpos.copy()[16:]
        return env_state

    def get_reward(self, physics):
        # return whether left gripper is holding the box
        all_contact_pairs = []
        for i_contact in range(physics.data.ncon):
            id_geom_1 = physics.data.contact[i_contact].geom1
            id_geom_2 = physics.data.contact[i_contact].geom2
            name_geom_1 = physics.model.id2name(id_geom_1, 'geom')
            name_geom_2 = physics.model.id2name(id_geom_2, 'geom')
            contact_pair = (name_geom_1, name_geom_2)
            all_contact_pairs.append(contact_pair)

        touch_left_gripper = ("red_box", "vx300s_left/10_left_gripper_finger") in all_contact_pairs
        touch_right_gripper = ("red_box", "vx300s_right/10_right_gripper_finger") in all_contact_pairs
        touch_table = ("red_box", "table") in all_contact_pairs

        reward = 0
        if touch_right_gripper:
            reward = 1
        if touch_right_gripper and not touch_table: # lifted
            reward = 2
        if touch_left_gripper: # attempted transfer
            reward = 3
        if touch_left_gripper and not touch_table: # successful transfer
            reward = 4
        return reward


class InsertionEETask(BimanualViperXEETask):
    def __init__(self, random=None):
        super().__init__(random=random)
        self.max_reward = 4

    def initialize_episode(self, physics):
        """Sets the state of the environment at the start of each episode."""
        self.initialize_robots(physics)
        # randomize peg and socket position
        peg_pose, socket_pose = sample_insertion_pose()
        id2index = lambda j_id: 16 + (j_id - 16) * 7 # first 16 is robot qpos, 7 is pose dim # hacky

        peg_start_id = physics.model.name2id('red_peg_joint', 'joint')
        peg_start_idx = id2index(peg_start_id)
        np.copyto(physics.data.qpos[peg_start_idx : peg_start_idx + 7], peg_pose)
        # print(f"randomized cube position to {cube_position}")

        socket_start_id = physics.model.name2id('blue_socket_joint', 'joint')
        socket_start_idx = id2index(socket_start_id)
        np.copyto(physics.data.qpos[socket_start_idx : socket_start_idx + 7], socket_pose)
        # print(f"randomized cube position to {cube_position}")

        super().initialize_episode(physics)

    @staticmethod
    def get_env_state(physics):
        env_state = physics.data.qpos.copy()[16:]
        return env_state

    def get_reward(self, physics):
        # return whether peg touches the pin
        all_contact_pairs = []
        for i_contact in range(physics.data.ncon):
            id_geom_1 = physics.data.contact[i_contact].geom1
            id_geom_2 = physics.data.contact[i_contact].geom2
            name_geom_1 = physics.model.id2name(id_geom_1, 'geom')
            name_geom_2 = physics.model.id2name(id_geom_2, 'geom')
            contact_pair = (name_geom_1, name_geom_2)
            all_contact_pairs.append(contact_pair)

        touch_right_gripper = ("red_peg", "vx300s_right/10_right_gripper_finger") in all_contact_pairs
        touch_left_gripper = ("socket-1", "vx300s_left/10_left_gripper_finger") in all_contact_pairs or \
                             ("socket-2", "vx300s_left/10_left_gripper_finger") in all_contact_pairs or \
                             ("socket-3", "vx300s_left/10_left_gripper_finger") in all_contact_pairs or \
                             ("socket-4", "vx300s_left/10_left_gripper_finger") in all_contact_pairs

        peg_touch_table = ("red_peg", "table") in all_contact_pairs
        socket_touch_table = ("socket-1", "table") in all_contact_pairs or \
                             ("socket-2", "table") in all_contact_pairs or \
                             ("socket-3", "table") in all_contact_pairs or \
                             ("socket-4", "table") in all_contact_pairs
        peg_touch_socket = ("red_peg", "socket-1") in all_contact_pairs or \
                           ("red_peg", "socket-2") in all_contact_pairs or \
                           ("red_peg", "socket-3") in all_contact_pairs or \
                           ("red_peg", "socket-4") in all_contact_pairs
        pin_touched = ("red_peg", "pin") in all_contact_pairs

        reward = 0
        if touch_left_gripper and touch_right_gripper: # touch both
            reward = 1
        if touch_left_gripper and touch_right_gripper and (not peg_touch_table) and (not socket_touch_table): # grasp both
            reward = 2
        if peg_touch_socket and (not peg_touch_table) and (not socket_touch_table): # peg and socket touching
            reward = 3
        if pin_touched: # successful insertion
            reward = 4
        return reward

	import numpy as np
	import collections
	import os

	from constants import DT, XML_DIR, START_ARM_POSE
	from constants import PUPPET_GRIPPER_POSITION_CLOSE
	from constants import PUPPET_GRIPPER_POSITION_UNNORMALIZE_FN
	from constants import PUPPET_GRIPPER_POSITION_NORMALIZE_FN
	from constants import PUPPET_GRIPPER_VELOCITY_NORMALIZE_FN

	from utils import sample_box_pose, sample_insertion_pose
	from dm_control import mujoco
	from dm_control.rl import control
	from dm_control.suite import base

	import IPython
	e = IPython.embed


	def make_ee_sim_env(task_name):
	"""
	Environment for simulated robot bi-manual manipulation, with end-effector control.
	Action space: [left_arm_pose (7), # position and quaternion for end effector
	left_gripper_positions (1), # normalized gripper position (0: close, 1: open)
	right_arm_pose (7), # position and quaternion for end effector
	right_gripper_positions (1),] # normalized gripper position (0: close, 1: open)

	Observation space: {"qpos": Concat[ left_arm_qpos (6), # absolute joint position
	left_gripper_position (1), # normalized gripper position (0: close, 1: open)
	right_arm_qpos (6), # absolute joint position
	right_gripper_qpos (1)] # normalized gripper position (0: close, 1: open)
	"qvel": Concat[ left_arm_qvel (6), # absolute joint velocity (rad)
	left_gripper_velocity (1), # normalized gripper velocity (pos: opening, neg: closing)
	right_arm_qvel (6), # absolute joint velocity (rad)
	right_gripper_qvel (1)] # normalized gripper velocity (pos: opening, neg: closing)
	"images": {"main": (480x640x3)} # h, w, c, dtype='uint8'
	"""
	if 'sim_transfer_cube' in task_name:
	xml_path = os.path.join(XML_DIR, f'bimanual_viperx_ee_transfer_cube.xml')
	physics = mujoco.Physics.from_xml_path(xml_path)
	task = TransferCubeEETask(random=False)
	env = control.Environment(physics, task, time_limit=20, control_timestep=DT,
	n_sub_steps=None, flat_observation=False)
	elif 'sim_insertion' in task_name:
	xml_path = os.path.join(XML_DIR, f'bimanual_viperx_ee_insertion.xml')
	physics = mujoco.Physics.from_xml_path(xml_path)
	task = InsertionEETask(random=False)
	env = control.Environment(physics, task, time_limit=20, control_timestep=DT,
	n_sub_steps=None, flat_observation=False)
	else:
	raise NotImplementedError
	return env

	class BimanualViperXEETask(base.Task):
	def __init__(self, random=None):
	super().__init__(random=random)

	def before_step(self, action, physics):
	a_len = len(action) // 2
	action_left = action[:a_len]
	action_right = action[a_len:]

	# set mocap position and quat
	# left
	np.copyto(physics.data.mocap_pos[0], action_left[:3])
	np.copyto(physics.data.mocap_quat[0], action_left[3:7])
	# right
	np.copyto(physics.data.mocap_pos[1], action_right[:3])
	np.copyto(physics.data.mocap_quat[1], action_right[3:7])

	# set gripper
	g_left_ctrl = PUPPET_GRIPPER_POSITION_UNNORMALIZE_FN(action_left[7])
	g_right_ctrl = PUPPET_GRIPPER_POSITION_UNNORMALIZE_FN(action_right[7])
	np.copyto(physics.data.ctrl, np.array([g_left_ctrl, -g_left_ctrl, g_right_ctrl, -g_right_ctrl]))

	def initialize_robots(self, physics):
	# reset joint position
	physics.named.data.qpos[:16] = START_ARM_POSE

	# reset mocap to align with end effector
	# to obtain these numbers:
	# (1) make an ee_sim env and reset to the same start_pose
	# (2) get env._physics.named.data.xpos['vx300s_left/gripper_link']
	# get env._physics.named.data.xquat['vx300s_left/gripper_link']
	# repeat the same for right side
	np.copyto(physics.data.mocap_pos[0], [-0.31718881, 0.5, 0.29525084])
	np.copyto(physics.data.mocap_quat[0], [1, 0, 0, 0])
	# right
	np.copyto(physics.data.mocap_pos[1], np.array([0.31718881, 0.49999888, 0.29525084]))
	np.copyto(physics.data.mocap_quat[1], [1, 0, 0, 0])

	# reset gripper control
	close_gripper_control = np.array([
	PUPPET_GRIPPER_POSITION_CLOSE,
	-PUPPET_GRIPPER_POSITION_CLOSE,
	PUPPET_GRIPPER_POSITION_CLOSE,
	-PUPPET_GRIPPER_POSITION_CLOSE,
	])
	np.copyto(physics.data.ctrl, close_gripper_control)

	def initialize_episode(self, physics):
	"""Sets the state of the environment at the start of each episode."""
	super().initialize_episode(physics)

	@staticmethod
	def get_qpos(physics):
	qpos_raw = physics.data.qpos.copy()
	left_qpos_raw = qpos_raw[:8]
	right_qpos_raw = qpos_raw[8:16]
	left_arm_qpos = left_qpos_raw[:6]
	right_arm_qpos = right_qpos_raw[:6]
	left_gripper_qpos = [PUPPET_GRIPPER_POSITION_NORMALIZE_FN(left_qpos_raw[6])]
	right_gripper_qpos = [PUPPET_GRIPPER_POSITION_NORMALIZE_FN(right_qpos_raw[6])]
	return np.concatenate([left_arm_qpos, left_gripper_qpos, right_arm_qpos, right_gripper_qpos])

	@staticmethod
	def get_qvel(physics):
	qvel_raw = physics.data.qvel.copy()
	left_qvel_raw = qvel_raw[:8]
	right_qvel_raw = qvel_raw[8:16]
	left_arm_qvel = left_qvel_raw[:6]
	right_arm_qvel = right_qvel_raw[:6]
	left_gripper_qvel = [PUPPET_GRIPPER_VELOCITY_NORMALIZE_FN(left_qvel_raw[6])]
	right_gripper_qvel = [PUPPET_GRIPPER_VELOCITY_NORMALIZE_FN(right_qvel_raw[6])]
	return np.concatenate([left_arm_qvel, left_gripper_qvel, right_arm_qvel, right_gripper_qvel])

	@staticmethod
	def get_env_state(physics):
	raise NotImplementedError

	def get_observation(self, physics):
	# note: it is important to do .copy()
	obs = collections.OrderedDict()
	obs['qpos'] = self.get_qpos(physics)
	obs['qvel'] = self.get_qvel(physics)
	obs['env_state'] = self.get_env_state(physics)
	obs['images'] = dict()
	obs['images']['top'] = physics.render(height=480, width=640, camera_id='top')
	obs['images']['angle'] = physics.render(height=480, width=640, camera_id='angle')
	obs['images']['vis'] = physics.render(height=480, width=640, camera_id='front_close')
	# used in scripted policy to obtain starting pose
	obs['mocap_pose_left'] = np.concatenate([physics.data.mocap_pos[0], physics.data.mocap_quat[0]]).copy()
	obs['mocap_pose_right'] = np.concatenate([physics.data.mocap_pos[1], physics.data.mocap_quat[1]]).copy()

	# used when replaying joint trajectory
	obs['gripper_ctrl'] = physics.data.ctrl.copy()
	return obs

	def get_reward(self, physics):
	raise NotImplementedError


	class TransferCubeEETask(BimanualViperXEETask):
	def __init__(self, random=None):
	super().__init__(random=random)
	self.max_reward = 4

	def initialize_episode(self, physics):
	"""Sets the state of the environment at the start of each episode."""
	self.initialize_robots(physics)
	# randomize box position
	cube_pose = sample_box_pose()
	box_start_idx = physics.model.name2id('red_box_joint', 'joint')
	np.copyto(physics.data.qpos[box_start_idx : box_start_idx + 7], cube_pose)
	# print(f"randomized cube position to {cube_position}")

	super().initialize_episode(physics)

	@staticmethod
	def get_env_state(physics):
	env_state = physics.data.qpos.copy()[16:]
	return env_state

	def get_reward(self, physics):
	# return whether left gripper is holding the box
	all_contact_pairs = []
	for i_contact in range(physics.data.ncon):
	id_geom_1 = physics.data.contact[i_contact].geom1
	id_geom_2 = physics.data.contact[i_contact].geom2
	name_geom_1 = physics.model.id2name(id_geom_1, 'geom')
	name_geom_2 = physics.model.id2name(id_geom_2, 'geom')
	contact_pair = (name_geom_1, name_geom_2)
	all_contact_pairs.append(contact_pair)

	touch_left_gripper = ("red_box", "vx300s_left/10_left_gripper_finger") in all_contact_pairs
	touch_right_gripper = ("red_box", "vx300s_right/10_right_gripper_finger") in all_contact_pairs
	touch_table = ("red_box", "table") in all_contact_pairs

	reward = 0
	if touch_right_gripper:
	reward = 1
	if touch_right_gripper and not touch_table: # lifted
	reward = 2
	if touch_left_gripper: # attempted transfer
	reward = 3
	if touch_left_gripper and not touch_table: # successful transfer
	reward = 4
	return reward


	class InsertionEETask(BimanualViperXEETask):
	def __init__(self, random=None):
	super().__init__(random=random)
	self.max_reward = 4

	def initialize_episode(self, physics):
	"""Sets the state of the environment at the start of each episode."""
	self.initialize_robots(physics)
	# randomize peg and socket position
	peg_pose, socket_pose = sample_insertion_pose()
	id2index = lambda j_id: 16 + (j_id - 16) * 7 # first 16 is robot qpos, 7 is pose dim # hacky

	peg_start_id = physics.model.name2id('red_peg_joint', 'joint')
	peg_start_idx = id2index(peg_start_id)
	np.copyto(physics.data.qpos[peg_start_idx : peg_start_idx + 7], peg_pose)
	# print(f"randomized cube position to {cube_position}")

	socket_start_id = physics.model.name2id('blue_socket_joint', 'joint')
	socket_start_idx = id2index(socket_start_id)
	np.copyto(physics.data.qpos[socket_start_idx : socket_start_idx + 7], socket_pose)
	# print(f"randomized cube position to {cube_position}")

	super().initialize_episode(physics)

	@staticmethod
	def get_env_state(physics):
	env_state = physics.data.qpos.copy()[16:]
	return env_state

	def get_reward(self, physics):
	# return whether peg touches the pin
	all_contact_pairs = []
	for i_contact in range(physics.data.ncon):
	id_geom_1 = physics.data.contact[i_contact].geom1
	id_geom_2 = physics.data.contact[i_contact].geom2
	name_geom_1 = physics.model.id2name(id_geom_1, 'geom')
	name_geom_2 = physics.model.id2name(id_geom_2, 'geom')
	contact_pair = (name_geom_1, name_geom_2)
	all_contact_pairs.append(contact_pair)

	touch_right_gripper = ("red_peg", "vx300s_right/10_right_gripper_finger") in all_contact_pairs
	touch_left_gripper = ("socket-1", "vx300s_left/10_left_gripper_finger") in all_contact_pairs or \
	("socket-2", "vx300s_left/10_left_gripper_finger") in all_contact_pairs or \
	("socket-3", "vx300s_left/10_left_gripper_finger") in all_contact_pairs or \
	("socket-4", "vx300s_left/10_left_gripper_finger") in all_contact_pairs

	peg_touch_table = ("red_peg", "table") in all_contact_pairs
	socket_touch_table = ("socket-1", "table") in all_contact_pairs or \
	("socket-2", "table") in all_contact_pairs or \
	("socket-3", "table") in all_contact_pairs or \
	("socket-4", "table") in all_contact_pairs
	peg_touch_socket = ("red_peg", "socket-1") in all_contact_pairs or \
	("red_peg", "socket-2") in all_contact_pairs or \
	("red_peg", "socket-3") in all_contact_pairs or \
	("red_peg", "socket-4") in all_contact_pairs
	pin_touched = ("red_peg", "pin") in all_contact_pairs

	reward = 0
	if touch_left_gripper and touch_right_gripper: # touch both
	reward = 1
	if touch_left_gripper and touch_right_gripper and (not peg_touch_table) and (not socket_touch_table): # grasp both
	reward = 2
	if peg_touch_socket and (not peg_touch_table) and (not socket_touch_table): # peg and socket touching
	reward = 3
	if pin_touched: # successful insertion
	reward = 4
	return reward