from typing import Any, Union
import numpy as np
import sapien
import torch
from mani_skill.agents.robots import Fetch, Panda
from mani_skill.envs.sapien_env import BaseEnv
from mani_skill.envs.utils import randomization
from mani_skill.sensors.camera import CameraConfig
from mani_skill.utils import common, sapien_utils
from mani_skill.utils.building import actors
from mani_skill.utils.registration import register_env
from mani_skill.utils.scene_builder.table import TableSceneBuilder
from mani_skill.utils.structs.pose import Pose
@register_env("StackCube-v1", max_episode_steps=50)
[docs]class StackCubeEnv(BaseEnv):
"""
**Task Description:**
The goal is to pick up a red cube and stack it on top of a green cube and let go of the cube without it falling
**Randomizations:**
- both cubes have their z-axis rotation randomized
- both cubes have their xy positions on top of the table scene randomized. The positions are sampled such that the cubes do not collide with each other
**Success Conditions:**
- the red cube is on top of the green cube (to within half of the cube size)
- the red cube is static
- the red cube is not being grasped by the robot (robot must let go of the cube)
"""
[docs] _sample_video_link = "https://github.com/haosulab/ManiSkill/raw/main/figures/environment_demos/StackCube-v1_rt.mp4"
[docs] SUPPORTED_ROBOTS = ["panda_wristcam", "panda", "fetch"]
[docs] agent: Union[Panda, Fetch]
def __init__(
self, *args, robot_uids="panda_wristcam", robot_init_qpos_noise=0.02, **kwargs
):
[docs] self.robot_init_qpos_noise = robot_init_qpos_noise
super().__init__(*args, robot_uids=robot_uids, **kwargs)
@property
[docs] def _default_sensor_configs(self):
pose = sapien_utils.look_at(eye=[0.3, 0, 0.6], target=[-0.1, 0, 0.1])
return [CameraConfig("base_camera", pose, 128, 128, np.pi / 2, 0.01, 100)]
@property
[docs] def _default_human_render_camera_configs(self):
pose = sapien_utils.look_at([0.6, 0.7, 0.6], [0.0, 0.0, 0.35])
return CameraConfig("render_camera", pose, 512, 512, 1, 0.01, 100)
[docs] def _load_agent(self, options: dict):
super()._load_agent(options, sapien.Pose(p=[-0.615, 0, 0]))
[docs] def _load_scene(self, options: dict):
self.cube_half_size = common.to_tensor([0.02] * 3, device=self.device)
self.table_scene = TableSceneBuilder(
env=self, robot_init_qpos_noise=self.robot_init_qpos_noise
)
self.table_scene.build()
self.cubeA = actors.build_cube(
self.scene,
half_size=0.02,
color=[1, 0, 0, 1],
name="cubeA",
initial_pose=sapien.Pose(p=[0, 0, 0.1]),
)
self.cubeB = actors.build_cube(
self.scene,
half_size=0.02,
color=[0, 1, 0, 1],
name="cubeB",
initial_pose=sapien.Pose(p=[1, 0, 0.1]),
)
[docs] def _initialize_episode(self, env_idx: torch.Tensor, options: dict):
with torch.device(self.device):
b = len(env_idx)
self.table_scene.initialize(env_idx)
xyz = torch.zeros((b, 3))
xyz[:, 2] = 0.02
xy = torch.rand((b, 2)) * 0.2 - 0.1
region = [[-0.1, -0.2], [0.1, 0.2]]
sampler = randomization.UniformPlacementSampler(
bounds=region, batch_size=b, device=self.device
)
radius = torch.linalg.norm(torch.tensor([0.02, 0.02])) + 0.001
cubeA_xy = xy + sampler.sample(radius, 100)
cubeB_xy = xy + sampler.sample(radius, 100, verbose=False)
xyz[:, :2] = cubeA_xy
qs = randomization.random_quaternions(
b,
lock_x=True,
lock_y=True,
lock_z=False,
)
self.cubeA.set_pose(Pose.create_from_pq(p=xyz.clone(), q=qs))
xyz[:, :2] = cubeB_xy
qs = randomization.random_quaternions(
b,
lock_x=True,
lock_y=True,
lock_z=False,
)
self.cubeB.set_pose(Pose.create_from_pq(p=xyz, q=qs))
[docs] def evaluate(self):
pos_A = self.cubeA.pose.p
pos_B = self.cubeB.pose.p
offset = pos_A - pos_B
xy_flag = (
torch.linalg.norm(offset[..., :2], axis=1)
<= torch.linalg.norm(self.cube_half_size[:2]) + 0.005
)
z_flag = torch.abs(offset[..., 2] - self.cube_half_size[..., 2] * 2) <= 0.005
is_cubeA_on_cubeB = torch.logical_and(xy_flag, z_flag)
# NOTE (stao): GPU sim can be fast but unstable. Angular velocity is rather high despite it not really rotating
is_cubeA_static = self.cubeA.is_static(lin_thresh=1e-2, ang_thresh=0.5)
is_cubeA_grasped = self.agent.is_grasping(self.cubeA)
success = is_cubeA_on_cubeB * is_cubeA_static * (~is_cubeA_grasped)
return {
"is_cubeA_grasped": is_cubeA_grasped,
"is_cubeA_on_cubeB": is_cubeA_on_cubeB,
"is_cubeA_static": is_cubeA_static,
"success": success.bool(),
}
[docs] def compute_dense_reward(self, obs: Any, action: torch.Tensor, info: dict):
# reaching reward
tcp_pose = self.agent.tcp.pose.p
cubeA_pos = self.cubeA.pose.p
cubeA_to_tcp_dist = torch.linalg.norm(tcp_pose - cubeA_pos, axis=1)
reward = 2 * (1 - torch.tanh(5 * cubeA_to_tcp_dist))
# grasp and place reward
cubeA_pos = self.cubeA.pose.p
cubeB_pos = self.cubeB.pose.p
goal_xyz = torch.hstack(
[cubeB_pos[:, 0:2], (cubeB_pos[:, 2] + self.cube_half_size[2] * 2)[:, None]]
)
cubeA_to_goal_dist = torch.linalg.norm(goal_xyz - cubeA_pos, axis=1)
place_reward = 1 - torch.tanh(5.0 * cubeA_to_goal_dist)
reward[info["is_cubeA_grasped"]] = (4 + place_reward)[info["is_cubeA_grasped"]]
# ungrasp and static reward
gripper_width = (self.agent.robot.get_qlimits()[0, -1, 1] * 2).to(
self.device
) # NOTE: hard-coded with panda
is_cubeA_grasped = info["is_cubeA_grasped"]
ungrasp_reward = (
torch.sum(self.agent.robot.get_qpos()[:, -2:], axis=1) / gripper_width
)
ungrasp_reward[~is_cubeA_grasped] = 1.0
v = torch.linalg.norm(self.cubeA.linear_velocity, axis=1)
av = torch.linalg.norm(self.cubeA.angular_velocity, axis=1)
static_reward = 1 - torch.tanh(v * 10 + av)
reward[info["is_cubeA_on_cubeB"]] = (
6 + (ungrasp_reward + static_reward) / 2.0
)[info["is_cubeA_on_cubeB"]]
reward[info["success"]] = 8
return reward
[docs] def compute_normalized_dense_reward(
self, obs: Any, action: torch.Tensor, info: dict
):
return self.compute_dense_reward(obs=obs, action=action, info=info) / 8