Go2Py_SIM/Go2Py/sim/mujoco.py

533 lines
19 KiB
Python

import time
import mujoco
import mujoco.viewer
import numpy as np
from Go2Py import ASSETS_PATH
import os
from scipy.spatial.transform import Rotation
import cv2
pnt = np.array([-0.2, 0, 0.05])
lidar_angles = np.linspace(0.0, 2 * np.pi, 1024).reshape(-1, 1)
x_vec = np.cos(lidar_angles)
y_vec = np.sin(lidar_angles)
z_vec = np.zeros_like(x_vec)
vec = np.concatenate([x_vec, y_vec, z_vec], axis=1)
nray = vec.shape[0]
geomid = np.zeros(nray, np.int32)
dist = np.zeros(nray, np.float64)
# Credit to: https://github.com/google-deepmind/mujoco/issues/1672
class Camera:
def __init__(self, resolution, model, data, cam_name: str = "", min_depth=0.35, max_depth=3.):
"""Initialize Camera instance.
Args:
- args: Arguments containing camera width and height.
- model: Mujoco model.
- data: Mujoco data.
- cam_name: Name of the camera.
- save_dir: Directory to save captured images.
"""
self._min_depth = min_depth
self._max_depth = max_depth
self._cam_name = cam_name
self._model = model
self._data = data
self._width = resolution[0]
self._height = resolution[1]
self._cam_id = self._data.cam(self._cam_name).id
self._renderer = mujoco.Renderer(self._model, self._height, self._width)
self._camera = mujoco.MjvCamera()
self._scene = mujoco.MjvScene(self._model, maxgeom=10_000)
self._image = np.zeros((self._height, self._width, 3), dtype=np.uint8)
self._depth_image = np.zeros((self._height, self._width, 1), dtype=np.float32)
self._seg_id_image = np.zeros((self._height, self._width, 3), dtype=np.float32)
self._point_cloud = np.zeros((self._height, self._width, 1), dtype=np.float32)
@property
def height(self) -> int:
"""
Get the height of the camera.
Returns:
int: The height of the camera.
"""
return self._height
@property
def width(self) -> int:
"""
Get the width of the camera.
Returns:
int: The width of the camera.
"""
return self._width
@property
def name(self) -> str:
"""
Get the name of the camera.
Returns:
str: The name of the camera.s
"""
return self._cam_name
@property
def K(self) -> np.ndarray:
"""
Compute the intrinsic camera matrix (K) based on the camera's field of view (fov),
width (_width), and height (_height) parameters, following the pinhole camera model.
Returns:
np.ndarray: The intrinsic camera matrix (K), a 3x3 array representing the camera's intrinsic parameters.
"""
# Convert the field of view from degrees to radians
theta = np.deg2rad(self.fov)
# Focal length calculation (f in terms of sensor width and height)
f_x = (self._width / 2) / np.tan(theta / 2)
f_y = (self._height / 2) / np.tan(theta / 2)
# Pixel resolution (assumed to be focal length per pixel unit)
alpha_u = f_x # focal length in terms of pixel width
alpha_v = f_y # focal length in terms of pixel height
# Optical center offsets (assuming they are at the center of the sensor)
u_0 = (self._width - 1) / 2.0
v_0 = (self._height - 1) / 2.0
# Intrinsic camera matrix K
K = np.array([[alpha_u, 0, u_0], [0, alpha_v, v_0], [0, 0, 1]])
return K
@property
def T_world_cam(self) -> np.ndarray:
"""
Compute the homogeneous transformation matrix for the camera.
The transformation matrix is computed from the camera's position and orientation.
The position and orientation are retrieved from the camera data.
Returns:
np.ndarray: The 4x4 homogeneous transformation matrix representing the camera's pose.
"""
pos = self._data.cam(self._cam_id).xpos
rot = self._data.cam(self._cam_id).xmat.reshape(3, 3).T
T = np.hstack([rot, pos.reshape(3,1)])
T = np.vstack([T, np.array([0., 0., 0., 1.])])
return T
@property
def P(self) -> np.ndarray:
"""
Compute the projection matrix for the camera.
The projection matrix is computed as the product of the camera's intrinsic matrix (K)
and the homogeneous transformation matrix (T_world_cam).
Returns:
np.ndarray: The 3x4 projection matrix.
"""
return self.K @ self.T_world_cam
@property
def image(self) -> np.ndarray:
"""Return the captured RGB image."""
self._renderer.update_scene(self._data, camera=self.name)
self._image = self._renderer.render()
return self._image
@property
def depth_image(self) -> np.ndarray:
"""Return the captured depth image."""
self._renderer.update_scene(self._data, camera=self.name)
self._renderer.enable_depth_rendering()
self._depth_image = self._renderer.render()
self._renderer.disable_depth_rendering()
return np.clip(self._depth_image, self._min_depth, self._max_depth)
@property
def seg_image(self) -> np.ndarray:
"""Return the captured segmentation image based on object's id."""
self._renderer.update_scene(self._data, camera=self.name)
self._renderer.enable_segmentation_rendering()
self._seg_id_image = self._renderer.render()[:, :, 0].reshape(
(self.height, self.width)
)
self._renderer.disable_segmentation_rendering()
return self._seg_id_image
@property
def point_cloud(self) -> np.ndarray:
"""Return the captured point cloud."""
self._point_cloud = self._depth_to_point_cloud(self.depth_image)
return self._point_cloud
@property
def fov(self) -> float:
"""Get the field of view (FOV) of the camera.
Returns:
- float: The field of view angle in degrees.
"""
return self._model.cam(self._cam_id).fovy[0]
@property
def id(self) -> int:
"""Get the identifier of the camera.
Returns:
- int: The identifier of the camera.
"""
return self._cam_id
def _depth_to_point_cloud(self, depth_image: np.ndarray) -> np.ndarray:
"""
Method to convert depth image to a point cloud in camera coordinates.
Args:
- depth_image: The depth image we want to convert to a point cloud.
Returns:
- np.ndarray: 3D points in camera coordinates.
"""
# Get image dimensions
dimg_shape = depth_image.shape
height = dimg_shape[0]
width = dimg_shape[1]
# Create pixel grid
y, x = np.meshgrid(np.arange(height), np.arange(width), indexing="ij")
# Flatten arrays for vectorized computation
x_flat = x.flatten()
y_flat = y.flatten()
depth_flat = depth_image.flatten()
# Negate depth values because z-axis goes into the camera
depth_flat = -depth_flat
# Stack flattened arrays to form homogeneous coordinates
homogeneous_coords = np.vstack((x_flat, y_flat, np.ones_like(x_flat)))
# Compute inverse of the intrinsic matrix K
K_inv = np.linalg.inv(self.K)
# Calculate 3D points in camera coordinates
points_camera = np.dot(K_inv, homogeneous_coords) * depth_flat
# Homogeneous coordinates to 3D points
points_camera = np.vstack((points_camera, np.ones_like(x_flat)))
points_camera = points_camera.T
# dehomogenize
points_camera = points_camera[:, :3] / points_camera[:, 3][:, np.newaxis]
return points_camera
class Go2Sim:
def __init__(self,
mode='lowlevel',
render=True,
dt=0.002,
height_map = None,
xml_path=None,
camera_name = "front_camera",
camera_resolution = (640, 480),
camera_depth_range = (0.35, 3.0),
friction_model = None,
):
if xml_path is None:
self.model = mujoco.MjModel.from_xml_path(
os.path.join(ASSETS_PATH, 'mujoco/go2.xml')
)
else:
self.model = mujoco.MjModel.from_xml_path(xml_path)
if height_map is not None:
try:
self.updateHeightMap(height_map)
except:
raise Exception('Could not set height map. Are you sure the XML contains the required asset?')
self.friction_model = friction_model
self.simulated = True
self.data = mujoco.MjData(self.model)
self.dt = dt
_render_dt = 1 / 60
self.render_ds_ratio = max(1, _render_dt // dt)
if render:
self.viewer = mujoco.viewer.launch_passive(self.model, self.data)
self.render = True
self.viewer.cam.distance = 3.0
self.viewer.cam.azimuth = 90
self.viewer.cam.elevation = -45
self.viewer.cam.lookat[:] = np.array([0.0, -0.25, 0.824])
else:
self.render = False
self.model.opt.gravity[2] = -9.81
self.model.opt.timestep = dt
self.renderer = None
self.render = render
self.step_counter = 0
self.prestanding_q = np.array([0.0, 1.26186061, -2.5,
0.0, 1.25883281, -2.5,
0.0, 1.27193761, -2.6,
0.0, 1.27148342, -2.6])
self.sitting_q = np.array([-0.02495611, 1.26249647, -2.82826662,
0.04563564, 1.2505368, -2.7933557,
-0.30623949, 1.28283751, -2.82314873,
0.26400229, 1.29355574, -2.84276843])
self.standing_q = np.array([0.0, 0.77832842, -1.56065452,
0.0, 0.76754963, -1.56634164,
0.0, 0.76681757, -1.53601146,
0.0, 0.75422204, -1.53229916])
self.q0 = self.sitting_q
self.pos0 = np.array([0., 0., 0.1])
self.rot0 = np.array([1., 0., 0., 0.])
self.reset()
mujoco.mj_step(self.model, self.data)
if self.render:
self.viewer.sync()
self.nv = self.model.nv
self.jacp = np.zeros((3, self.nv))
self.jacr = np.zeros((3, self.nv))
self.M = np.zeros((self.nv, self.nv))
self.q_des = np.zeros(12)
self.dq_des = np.zeros(12)
self.tau_ff = np.zeros(12)
self.kp = np.zeros(12)
self.kv = np.zeros(12)
self.latest_command_stamp = time.time()
self.actuator_tau = np.zeros(12)
self.mode = mode
if self.mode == 'highlevel':
from Go2Py.control.walk_these_ways import CommandInterface, loadParameters, Policy, WalkTheseWaysAgent, HistoryWrapper
checkpoint_path = os.path.join(ASSETS_PATH,'checkpoints/walk_these_ways')
self.cfg = loadParameters(checkpoint_path)
self.policy = Policy(checkpoint_path)
self.command_profile = CommandInterface()
self.agent = WalkTheseWaysAgent(self.cfg, self.command_profile, robot=self)
self.agent = HistoryWrapper(self.agent)
self.control_dt = self.cfg["control"]["decimation"] * self.cfg["sim"]["dt"]
self.obs = self.agent.reset()
self.standUpReset()
self.step_counter = 0
self.step = self.stepHighlevel
self.ex_sum=0
self.ey_sum=0
self.e_omega_sum=0
else:
self.step = self.stepLowlevel
self.camera_name = camera_name
self.camera_resolution = camera_resolution
self.camera_depth_range = camera_depth_range
self.camera = Camera(self.camera_resolution, self.model, self.data, self.camera_name, min_depth=self.camera_depth_range[0] ,max_depth=self.camera_depth_range[1])
def updateHeightMap(self, height_map, hfield_size = (300,300), raw_deoth_to_height_ratio = 255.):
try:
map = cv2.resize(height_map, hfield_size)/raw_deoth_to_height_ratio
self.height_map = np.flip(map, axis=0).reshape(-1)
self.model.hfield_data = self.height_map
if self.render:
self.viewer.update_hfield(0)
except:
raise Exception(f'Could not load heightmap. Make sure the heigh_map is a 2D numpy array')
def reset(self, q0=None):
if q0 is None:
self.q_nominal = np.hstack(
[self.pos0.squeeze(), self.rot0.squeeze(), self.q0.squeeze()]
)
else:
assert q0.shape == (19,), 'Invalid q0 shape. The shape should be (19,)'
self.q_nominal = q0
self.data.qpos = self.q_nominal
self.data.qvel = np.zeros(18)
self.ex_sum=0
self.ey_sum=0
self.e_omega_sum=0
mujoco.mj_step(self.model, self.data)
if self.render:
self.viewer.sync()
def standUpReset(self):
self.q0 = self.standing_q
self.pos0 = np.array([0., 0., 0.33])
self.rot0 = np.array([1., 0., 0., 0.])
self.reset()
mujoco.mj_step(self.model, self.data)
if self.render:
self.viewer.sync()
def sitDownReset(self):
self.q0 = self.sitting_q
self.pos0 = np.array([0., 0., 0.1])
self.rot0 = np.array([1., 0., 0., 0.])
self.reset()
mujoco.mj_step(self.model, self.data)
if self.render:
self.viewer.sync()
def getJointStates(self):
return {"q": self.data.qpos[7:],
"dq": self.data.qvel[6:],
'tau_est': self.actuator_tau}
def getPose(self):
return self.data.qpos[:3], self.data.qpos[3:7]
def getIMU(self):
return {
'accel': np.array(self.data.sensordata[0:3]),
'gyro': np.array(self.data.sensordata[3:6])
}
def getFootContact(self):
return self.data.sensordata[6:10]
def setCommands(self, q_des, dq_des, kp, kv, tau_ff):
self.q_des = q_des
self.dq_des = dq_des
self.kp = kp
self.kv = kv
self.tau_ff = tau_ff
self.latest_command_stamp = time.time()
def stepLowlevel(self):
state = self.getJointStates()
q, dq = state['q'], state['dq']
tau = np.diag(self.kp) @ (self.q_des - q).reshape(12, 1) + \
np.diag(self.kv) @ (self.dq_des - dq).reshape(12, 1) + self.tau_ff.reshape(12, 1)
# Apply the friction model if it is provided to the simulator
if self.friction_model is not None:
tau = tau.squeeze()-self.friction_model(dq)
self.actuator_tau = tau
self.data.ctrl[:] = tau.squeeze()
self.step_counter += 1
mujoco.mj_step(self.model, self.data)
# Render every render_ds_ratio steps (60Hz GUI update)
if self.render and (self.step_counter % self.render_ds_ratio) == 0:
self.viewer.sync()
def getLinVel(self):
_, q = self.getPose()
world_R_body = Rotation.from_quat([q[1], q[2], q[3], q[0]]).as_matrix()
body_v = world_R_body.T@self.data.qvel[0:3].reshape(3,1)
return body_v
def getFootVelInWorld(self, site_name):
Jp, Jr = self.getSiteJacobian(site_name)
foot_vel = Jp@self.data.qvel.reshape(-1,1)
return foot_vel
def stepHighlevel(self, vx, vy, omega_z, body_z_offset=0, step_height = 0.08, kp=[2, 0.5, 0.5], ki=[0.02, 0.01, 0.01]):
policy_info = {}
if self.step_counter % (self.control_dt // self.dt) == 0:
action = self.policy(self.obs, policy_info)
self.obs, ret, done, info = self.agent.step(action)
#Body velocity tracker PI controller
_, q = self.getPose()
world_R_body = Rotation.from_quat([q[1], q[2], q[3], q[0]]).as_matrix()
body_v = world_R_body.T@self.data.qvel[0:3].reshape(3,1)
ex = (vx-body_v[0])
ey = (vy-body_v[1])
e_omega = (omega_z-self.data.qvel[5])
self.ex_sum+=ex
self.ey_sum+=ey
self.e_omega_sum+=e_omega
self.command_profile.yaw_vel_cmd = np.clip(kp[2]*e_omega+ki[2]*self.e_omega_sum + omega_z, -2*np.pi, 2*np.pi)
self.command_profile.x_vel_cmd = np.clip(kp[0]*ex+ki[0]*self.ex_sum + vx, -2.5, 2.5)
self.command_profile.y_vel_cmd = np.clip(kp[1]*ey+ki[1]*self.ey_sum + vy,-1.5, 1.5)
self.command_profile.body_height_cmd = body_z_offset
self.command_profile.footswing_height_cmd = step_height
self.step_counter+=1
self.stepLowlevel()
def getSiteJacobian(self, site_name):
id = mujoco.mj_name2id(self.model, mujoco.mjtObj.mjOBJ_SITE, site_name)
assert id > 0, 'The requested site could not be found'
mujoco.mj_jacSite(self.model, self.data, self.jacp, self.jacr, id)
return self.jacp, self.jacr
def getDynamicsParams(self):
mujoco.mj_fullM(self.model, self.M, self.data.qM)
nle = self.data.qfrc_bias.reshape(self.nv, 1)
return {
'M': self.M,
'nle': nle
}
def getGravityInBody(self):
_, q = self.getPose()
R = Rotation.from_quat([q[1], q[2], q[3], q[0]]).as_matrix()
g_in_body = R.T @ np.array([0.0, 0.0, -1.0]).reshape(3, 1)
return g_in_body
def getLaserScan(self, max_range=30):
t, q = self.getPose()
world_R_body = Rotation.from_quat([q[1], q[2], q[3], q[0]]).as_matrix()
pnt = t.copy()
pnt[2]+=0.25
vec_in_w = (world_R_body@vec.T).T
mujoco.mj_multiRay(
m=self.model,
d=self.data,
pnt=pnt,
vec=vec_in_w.flatten(),
geomgroup=None,
flg_static=1,
bodyexclude=-1,
geomid=geomid,
dist=dist,
nray=nray,
cutoff=max_range#mujoco.mjMAXVAL,
)
pcd = dist.reshape(-1, 1) * vec
idx = np.where(np.logical_and(dist!=-1, dist<max_range))[0]
return {"pcd": pcd[idx,...], "geomid": geomid[idx,...], "dist": dist[idx,...]}
def getCameraState(self, get_pointcloud=False):
depth = self.camera.depth_image
img = self.camera.image
K = self.camera.K
world_T_camera = self.camera.depth_image
fov = self.camera.fov
if get_pointcloud:
pointcloud = self.camera.point_cloud
else:
pointcloud = None
return {
'depth':depth,
'rgb':img,
'K': K,
'world_T_camera': world_T_camera,
'fovy': fov,
'pointcloud':pointcloud
}
def overheat(self):
return False
def close(self):
if self.render:
self.viewer.close()