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import numpy as np
import pinocchio as pin
from decoupled_wbc.control.robot_model.supplemental_info import RobotSupplementalInfo
class RobotModel:
def __init__(
self,
urdf_path,
asset_path,
set_floating_base=False,
supplemental_info: Optional[RobotSupplementalInfo] = None,
):
self.pinocchio_wrapper = pin.RobotWrapper.BuildFromURDF(
filename=urdf_path,
package_dirs=[asset_path],
root_joint=pin.JointModelFreeFlyer() if set_floating_base else None,
)
self.is_floating_base_model = set_floating_base
self.joint_to_dof_index = {}
# Assume we only have single-dof joints
# First two names correspond to universe and floating base joints
names = (
self.pinocchio_wrapper.model.names[2:]
if set_floating_base
else self.pinocchio_wrapper.model.names[1:]
)
for name in names:
j_id = self.pinocchio_wrapper.model.getJointId(name)
jmodel = self.pinocchio_wrapper.model.joints[j_id]
self.joint_to_dof_index[name] = jmodel.idx_q
# Store joint limits only for actual joints (excluding floating base)
# if set floating base is true and the robot can move in the world
# then we don't want to impose joint limits for the 7 dofs corresponding
# to the floating base dofs.
root_nq = 7 if set_floating_base else 0
self.upper_joint_limits = self.pinocchio_wrapper.model.upperPositionLimit[root_nq:].copy()
self.lower_joint_limits = self.pinocchio_wrapper.model.lowerPositionLimit[root_nq:].copy()
# Set up supplemental info if provided
self.supplemental_info = supplemental_info
if self.supplemental_info is not None:
# Cache indices for body and hand actuated joints separately
self._body_actuated_joint_indices = [
self.dof_index(name) for name in self.supplemental_info.body_actuated_joints
]
self._left_hand_actuated_joint_indices = [
self.dof_index(name) for name in self.supplemental_info.left_hand_actuated_joints
]
self._right_hand_actuated_joint_indices = [
self.dof_index(name) for name in self.supplemental_info.right_hand_actuated_joints
]
self._hand_actuated_joint_indices = (
self._left_hand_actuated_joint_indices + self._right_hand_actuated_joint_indices
)
# Cache indices for joint groups, handling nested groups
self._joint_group_indices = {}
for group_name, group_info in self.supplemental_info.joint_groups.items():
indices = []
# Add indices for direct joints
indices.extend([self.dof_index(name) for name in group_info["joints"]])
# Add indices from subgroups
for subgroup_name in group_info["groups"]:
indices.extend(self.get_joint_group_indices(subgroup_name))
self._joint_group_indices[group_name] = sorted(set(indices))
# Update joint limits from supplemental info if available
if (
hasattr(self.supplemental_info, "joint_limits")
and self.supplemental_info.joint_limits
):
for joint_name, limits in self.supplemental_info.joint_limits.items():
if joint_name in self.joint_to_dof_index:
idx = self.joint_to_dof_index[joint_name] - root_nq
self.lower_joint_limits[idx] = limits[0]
self.upper_joint_limits[idx] = limits[1]
# Initialize default body pose
self.default_body_pose = self.q_zero.copy()
# Update with supplemental info if available
if self.supplemental_info is not None:
default_joint_q = self.supplemental_info.default_joint_q
for joint, joint_values in default_joint_q.items():
# Get the joint name mapping for this type
joint_mapping = self.supplemental_info.joint_name_mapping[joint]
# Handle both single joint names and left/right mappings
if isinstance(joint_mapping, str):
# Single joint (e.g., waist joints)
if joint_mapping in self.joint_to_dof_index:
joint_idx = self.dof_index(joint_mapping)
self.default_body_pose[joint_idx] = (
joint_values # joint_values is the value for single joints
)
else:
# Left/right mapping (e.g., arm joints)
for side, value in joint_values.items():
if side in joint_mapping and joint_mapping[side] in self.joint_to_dof_index:
joint_idx = self.dof_index(joint_mapping[side])
self.default_body_pose[joint_idx] = value
# Initialize initial body pose
self.initial_body_pose = self.default_body_pose.copy()
@property
def num_dofs(self) -> int:
"""Get the number of degrees of freedom of the robot (floating base pose + joints)."""
return self.pinocchio_wrapper.model.nq
@property
def q_zero(self) -> np.ndarray:
"""Get the zero pose of the robot."""
return self.pinocchio_wrapper.q0
@property
def joint_names(self) -> List[str]:
"""Get the names of the joints of the robot."""
return list(self.joint_to_dof_index.keys())
@property
def num_joints(self) -> int:
"""Get the number of joints of the robot."""
return len(self.joint_to_dof_index)
def dof_index(self, joint_name: str) -> int:
"""
Get the index in the degrees of freedom vector corresponding
to the single-DoF joint with name `joint_name`.
"""
if joint_name not in self.joint_to_dof_index:
raise ValueError(
f"Unknown joint name: '{joint_name}'. "
f"Available joints: {list(self.joint_to_dof_index.keys())}"
)
return self.joint_to_dof_index[joint_name]
def get_body_actuated_joint_indices(self) -> List[int]:
"""
Get the indices of body actuated joints in the full configuration.
Ordering is that of the actuated joints as defined in the supplemental info.
Requires supplemental_info to be provided.
"""
if self.supplemental_info is None:
raise ValueError("supplemental_info must be provided to use this method")
return self._body_actuated_joint_indices
def get_hand_actuated_joint_indices(self, side: str = "both") -> List[int]:
"""
Get the indices of hand actuated joints in the full configuration.
Ordering is that of the actuated joints as defined in the supplemental info.
Requires supplemental_info to be provided.
Args:
side: String specifying which hand to get indices for ('left', 'right', or 'both')
"""
if self.supplemental_info is None:
raise ValueError("supplemental_info must be provided to use this method")
if side.lower() == "both":
return self._hand_actuated_joint_indices
elif side.lower() == "left":
return self._left_hand_actuated_joint_indices
elif side.lower() == "right":
return self._right_hand_actuated_joint_indices
else:
raise ValueError("side must be 'left', 'right', or 'both'")
def get_joint_group_indices(self, group_names: Union[str, Set[str]]) -> List[int]:
"""
Get the indices of joints in one or more groups in the full configuration.
Requires supplemental_info to be provided.
The returned indices are sorted in ascending order, so that the joint ordering
of the full model is preserved.
Args:
group_names: Either a single group name (str) or a set of group names (Set[str])
Returns:
List of joint indices in sorted order with no duplicates
"""
if self.supplemental_info is None:
raise ValueError("supplemental_info must be provided to use this method")
# Convert single string to set for uniform handling
if isinstance(group_names, str):
group_names = {group_names}
# Collect indices from all groups
all_indices = set()
for group_name in group_names:
if group_name not in self._joint_group_indices:
raise ValueError(f"Unknown joint group: {group_name}")
all_indices.update(self._joint_group_indices[group_name])
return sorted(all_indices)
def cache_forward_kinematics(self, q: np.ndarray, auto_clip=True) -> None:
"""
Perform forward kinematics to update the pose of every joint and frame
in the Pinocchio data structures for the given configuration `q`.
:param q: A numpy array of shape (num_dofs,) representing the robot configuration.
"""
if q.shape[0] != self.num_dofs:
raise ValueError(f"Expected q of length {self.num_dofs}, got {q.shape[0]} instead.")
# Apply auto-clip if enabled
if auto_clip:
q = self.clip_configuration(q)
pin.framesForwardKinematics(self.pinocchio_wrapper.model, self.pinocchio_wrapper.data, q)
def compute_gravity_compensation_torques(
self, q: np.ndarray, joint_groups: Union[str, List[str], Set[str]] = None, auto_clip=True
) -> np.ndarray:
"""
Compute gravity compensation torques for specified joint groups using pinocchio.
:param q: Robot configuration (joint positions)
:param joint_groups: Joint groups to compensate (e.g., "arms", ["left_arm", "waist"],
{"left_arm", "waist"}). If None, compensates all joints
:param auto_clip: Whether to automatically clip joint values to limits
:return: Array of gravity compensation torques for all DOFs (zero for non-compensated joints)
"""
if q.shape[0] != self.num_dofs:
raise ValueError(f"Expected q of length {self.num_dofs}, got {q.shape[0]} instead.")
# Apply auto-clip if enabled
if auto_clip:
q = self.clip_configuration(q)
try:
# Cache forward kinematics for the current configuration
self.cache_forward_kinematics(q, auto_clip=False) # Already clipped if needed
# Compute gravity vector using RNEA with zero velocity and acceleration
v = np.zeros(self.num_dofs)
a = np.zeros(self.num_dofs)
gravity_torques_full = pin.rnea(
self.pinocchio_wrapper.model, self.pinocchio_wrapper.data, q, v, a
)
# If no joint groups specified, return full gravity torques
if joint_groups is None:
return gravity_torques_full
# Convert list to set for get_joint_group_indices compatibility
if isinstance(joint_groups, list):
joint_groups = set(joint_groups)
# Get joint indices for specified groups - get_joint_group_indices handles str and Set[str]
try:
compensated_joint_indices = self.get_joint_group_indices(joint_groups)
except ValueError as e:
raise ValueError(f"Error resolving joint groups {joint_groups}: {e}")
# Create mask for joints that should receive gravity compensation
compensation_mask = np.zeros(self.num_dofs, dtype=bool)
for joint_idx in compensated_joint_indices:
if 0 <= joint_idx < len(compensation_mask):
compensation_mask[joint_idx] = True
# Apply mask to only compensate specified joints
compensated_torques = np.zeros_like(gravity_torques_full)
compensated_torques[compensation_mask] = gravity_torques_full[compensation_mask]
return compensated_torques
except Exception as e:
raise RuntimeError(f"Error computing gravity compensation: {e}")
def clip_configuration(self, q: np.ndarray, margin: float = 1e-6) -> np.ndarray:
"""
Clip the configuration to stay within joint limits with a small tolerance.
:param q: Configuration to clip
:param margin: Tolerance to keep away from joint limits
:return: Clipped configuration
"""
q_clipped = q.copy()
# Only clip joint positions, not floating base
root_nq = 7 if self.is_floating_base_model else 0
q_clipped[root_nq:] = np.clip(
q[root_nq:], self.lower_joint_limits + margin, self.upper_joint_limits - margin
)
return q_clipped
def frame_placement(self, frame_name: str) -> pin.SE3:
"""
Returns the SE3 transform of the specified frame in the world coordinate system.
Note: make sure cache_forward_kinematics() has been previously called.
:param frame_name: Name of the frame, e.g. "link_elbow_frame", "hand_imu_frame", etc.
:return: A pin.SE3 object representing the pose of the frame.
"""
model = self.pinocchio_wrapper.model
data = self.pinocchio_wrapper.data
frame_id = model.getFrameId(frame_name)
if frame_id < 0 or frame_id >= len(model.frames):
valid_frames = [f.name for f in model.frames]
raise ValueError(f"Unknown frame '{frame_name}'. Valid frames: {valid_frames}")
# Pinocchio's data.oMf[frame_id] is a pin.SE3.
return data.oMf[frame_id].copy()
def get_body_actuated_joints(self, q: np.ndarray) -> np.ndarray:
"""
Get the configuration of body actuated joints from a full configuration.
:param q: Configuration in full space
:return: Configuration of body actuated joints
"""
indices = self.get_body_actuated_joint_indices()
return q[indices]
def get_hand_actuated_joints(self, q: np.ndarray, side: str = "both") -> np.ndarray:
"""
Get the configuration of hand actuated joints from a full configuration.
Args:
q: Configuration in full space
side: String specifying which hand to get joints for ('left', 'right', or 'both')
"""
indices = self.get_hand_actuated_joint_indices(side)
return q[indices]
def get_configuration_from_actuated_joints(
self,
body_actuated_joint_values: np.ndarray,
hand_actuated_joint_values: Optional[np.ndarray] = None,
left_hand_actuated_joint_values: Optional[np.ndarray] = None,
right_hand_actuated_joint_values: Optional[np.ndarray] = None,
) -> np.ndarray:
"""
Get the full configuration from the body and hand actuated joint configurations.
Can specify either both hands together or left and right hands separately.
Args:
body_actuated_joint_values: Configuration of body actuated joints
hand_actuated_joint_values: Configuration of both hands' actuated joints (optional)
left_hand_actuated_joint_values: Configuration of left hand actuated joints (optional)
right_hand_actuated_joint_values: Configuration of right hand actuated joints (optional)
Returns:
Full configuration including body and hand joints
"""
q = self.pinocchio_wrapper.q0.copy()
q[self.get_body_actuated_joint_indices()] = body_actuated_joint_values
# Handle hand configurations
if hand_actuated_joint_values is not None:
# Use combined hand configuration
q[self.get_hand_actuated_joint_indices("both")] = hand_actuated_joint_values
else:
# Use separate hand configurations
if left_hand_actuated_joint_values is not None:
q[self.get_hand_actuated_joint_indices("left")] = left_hand_actuated_joint_values
if right_hand_actuated_joint_values is not None:
q[self.get_hand_actuated_joint_indices("right")] = right_hand_actuated_joint_values
return q
def reset_forward_kinematics(self) -> None:
"""
Reset the forward kinematics to the initial configuration.
"""
self.cache_forward_kinematics(self.q_zero)
def get_initial_upper_body_pose(self) -> np.ndarray:
"""
Get the initial upper body pose of the robot.
"""
return self.initial_body_pose[self.get_joint_group_indices("upper_body")]
def get_default_body_pose(self) -> np.ndarray:
"""
Get the default body pose of the robot.
"""
return self.default_body_pose
def set_initial_body_pose(self, q: np.ndarray, q_idx=None) -> None:
"""
Set the initial body pose of the robot.
"""
if q_idx is None:
self.initial_body_pose = q
else:
self.initial_body_pose[q_idx] = q
class ReducedRobotModel(RobotModel):
"""
A class that creates a reduced order robot model by fixing certain joints.
This class maintains a mapping between the reduced state space and the full state space.
"""
def __init__(
self,
full_robot_model: RobotModel,
fixed_joints: List[str],
fixed_values: Optional[List[float]] = None,
):
"""
Create a reduced order robot model by fixing specified joints.
:param full_robot_model: The original robot model
:param fixed_joints: List of joint names to fix
:param fixed_values: Optional list of values to fix the joints to. If None, uses the initial
joint positions (q0) from the full robot model.
"""
self.full_robot = full_robot_model
self.supplemental_info = full_robot_model.supplemental_info
# If fixed_values is None, use q0 from the full robot model
if fixed_values is None:
fixed_values = []
for joint_name in fixed_joints:
full_idx = full_robot_model.dof_index(joint_name)
fixed_values.append(full_robot_model.pinocchio_wrapper.q0[full_idx])
elif len(fixed_joints) != len(fixed_values):
raise ValueError("fixed_joints and fixed_values must have the same length")
# Store fixed joints and their values
self.fixed_joints = fixed_joints
self.fixed_values = fixed_values
# Create mapping between reduced and full state spaces
self.reduced_to_full = []
self.full_to_reduced = {}
# Initialize with floating base indices if present
if full_robot_model.is_floating_base_model:
self.reduced_to_full.extend(range(7)) # Floating base indices
for i in range(7):
self.full_to_reduced[i] = i
# Add active joint indices
for joint_name in full_robot_model.joint_names:
if joint_name not in fixed_joints:
full_idx = full_robot_model.dof_index(joint_name)
reduced_idx = len(self.reduced_to_full)
self.reduced_to_full.append(full_idx)
self.full_to_reduced[full_idx] = reduced_idx
# Create a reduced Pinocchio model using buildReducedModel
# First, get the list of joint IDs to lock
locked_joint_ids = []
for joint_name in fixed_joints:
joint_id = full_robot_model.pinocchio_wrapper.model.getJointId(joint_name)
if (full_robot_model.is_floating_base_model and joint_id > 1) or (
not full_robot_model.is_floating_base_model and joint_id > 0
):
locked_joint_ids.append(joint_id)
# First build the reduced kinematic model
reduced_model = pin.buildReducedModel(
full_robot_model.pinocchio_wrapper.model,
locked_joint_ids,
full_robot_model.pinocchio_wrapper.q0,
)
# Then build the reduced geometry models using the reduced kinematic model
self.pinocchio_wrapper = pin.RobotWrapper(
model=reduced_model,
)
# Create joint to dof index mapping
self.joint_to_dof_index = {}
# Assume we only have single-dof joints
# First two names correspond to universe and floating base joints
names = (
self.pinocchio_wrapper.model.names[2:]
if self.full_robot.is_floating_base_model
else self.pinocchio_wrapper.model.names[1:]
)
for name in names:
j_id = self.pinocchio_wrapper.model.getJointId(name)
jmodel = self.pinocchio_wrapper.model.joints[j_id]
self.joint_to_dof_index[name] = jmodel.idx_q
# Initialize joint limits
root_nq = 7 if self.full_robot.is_floating_base_model else 0
self.lower_joint_limits = self.pinocchio_wrapper.model.lowerPositionLimit[root_nq:].copy()
self.upper_joint_limits = self.pinocchio_wrapper.model.upperPositionLimit[root_nq:].copy()
# Update joint limits from supplemental info if available
if self.supplemental_info is not None:
if (
hasattr(self.supplemental_info, "joint_limits")
and self.supplemental_info.joint_limits
):
for joint_name, limits in self.supplemental_info.joint_limits.items():
if joint_name in self.joint_to_dof_index:
idx = self.joint_to_dof_index[joint_name] - root_nq
self.lower_joint_limits[idx] = limits[0]
self.upper_joint_limits[idx] = limits[1]
# Get full indices for body and hand actuated joints
full_body_indices = full_robot_model.get_body_actuated_joint_indices()
full_hand_indices = full_robot_model.get_hand_actuated_joint_indices("both")
full_left_hand_indices = full_robot_model.get_hand_actuated_joint_indices("left")
full_right_hand_indices = full_robot_model.get_hand_actuated_joint_indices("right")
# Map to reduced indices
self._body_actuated_joint_indices = []
for idx in full_body_indices:
if idx in self.full_to_reduced:
self._body_actuated_joint_indices.append(self.full_to_reduced[idx])
self._hand_actuated_joint_indices = []
for idx in full_hand_indices:
if idx in self.full_to_reduced:
self._hand_actuated_joint_indices.append(self.full_to_reduced[idx])
self._left_hand_actuated_joint_indices = []
for idx in full_left_hand_indices:
if idx in self.full_to_reduced:
self._left_hand_actuated_joint_indices.append(self.full_to_reduced[idx])
self._right_hand_actuated_joint_indices = []
for idx in full_right_hand_indices:
if idx in self.full_to_reduced:
self._right_hand_actuated_joint_indices.append(self.full_to_reduced[idx])
# Cache indices for joint groups in reduced space
self._joint_group_indices = {}
for group_name in self.supplemental_info.joint_groups:
full_indices = full_robot_model.get_joint_group_indices(group_name)
reduced_indices = []
for idx in full_indices:
if idx in self.full_to_reduced:
reduced_indices.append(self.full_to_reduced[idx])
self._joint_group_indices[group_name] = sorted(set(reduced_indices))
# Initialize default body pose in reduced space
self.default_body_pose = self.full_to_reduced_configuration(
full_robot_model.default_body_pose
)
# Initialize initial body pose in reduced space
self.initial_body_pose = self.full_to_reduced_configuration(
full_robot_model.initial_body_pose
)
@property
def num_joints(self) -> int:
"""Get the number of active joints in the reduced model."""
return len(self.joint_names)
@property
def joint_names(self) -> List[str]:
"""Get the names of the active joints in the reduced model."""
return [name for name in self.full_robot.joint_names if name not in self.fixed_joints]
@classmethod
def from_fixed_groups(
cls,
full_robot_model: RobotModel,
fixed_group_names: List[str],
fixed_values: Optional[List[float]] = None,
) -> "ReducedRobotModel":
"""
Create a reduced order robot model by fixing all joints in specified groups.
:param full_robot_model: The original robot model
:param fixed_group_names: List of joint group names to fix
:param fixed_values: Optional list of values to fix the joints to. If None, uses the initial
joint positions (q0) from the full robot model.
:return: A ReducedRobotModel instance
"""
if full_robot_model.supplemental_info is None:
raise ValueError("supplemental_info must be provided to use this method")
# Get all joints in the groups, including those from subgroups
fixed_joints = set() # Use a set to avoid duplicates
for group_name in fixed_group_names:
if group_name not in full_robot_model.supplemental_info.joint_groups:
raise ValueError(f"Unknown joint group: {group_name}")
group_info = full_robot_model.supplemental_info.joint_groups[group_name]
# Add direct joints
fixed_joints.update(group_info["joints"])
# Add joints from subgroups
for subgroup_name in group_info["groups"]:
subgroup_joints = full_robot_model.get_joint_group_indices(subgroup_name)
fixed_joints.update([full_robot_model.joint_names[idx] for idx in subgroup_joints])
# Convert set back to list for compatibility with the original constructor
return cls(full_robot_model, list(fixed_joints), fixed_values)
@classmethod
def from_fixed_group(
cls,
full_robot_model: RobotModel,
fixed_group_name: str,
fixed_values: Optional[List[float]] = None,
) -> "ReducedRobotModel":
"""
Create a reduced order robot model by fixing all joints in a specified group.
This is a convenience method that calls from_fixed_groups with a single group.
:param full_robot_model: The original robot model
:param fixed_group_name: Name of the joint group to fix
:param fixed_values: Optional list of values to fix the joints to. If None, uses the initial
joint positions (q0) from the full robot model.
:return: A ReducedRobotModel instance
"""
return cls.from_fixed_groups(full_robot_model, [fixed_group_name], fixed_values)
@classmethod
def from_active_group(
cls,
full_robot_model: RobotModel,
active_group_name: str,
fixed_values: Optional[List[float]] = None,
) -> "ReducedRobotModel":
"""
Create a reduced order robot model by fixing all joints EXCEPT those in the specified group.
This is a convenience method that calls from_active_groups with a single group.
:param full_robot_model: The original robot model
:param active_group_name: Name of the joint group to keep active (all other joints will be fixed)
:param fixed_values: Optional list of values to fix the joints to. If None, uses the initial
joint positions (q0) from the full robot model.
:return: A ReducedRobotModel instance
"""
return cls.from_active_groups(full_robot_model, [active_group_name], fixed_values)
@classmethod
def from_active_groups(
cls,
full_robot_model: RobotModel,
active_group_names: List[str],
fixed_values: Optional[List[float]] = None,
) -> "ReducedRobotModel":
"""
Create a reduced order robot model by fixing all joints EXCEPT those in the specified groups.
This is useful when you want to keep multiple groups active and fix everything else.
:param full_robot_model: The original robot model
:param active_group_names: List of joint group names to keep active (all other joints will be fixed)
:param fixed_values: Optional list of values to fix the joints to. If None, uses the initial
joint positions (q0) from the full robot model.
:return: A ReducedRobotModel instance
"""
if full_robot_model.supplemental_info is None:
raise ValueError("supplemental_info must be provided to use this method")
# Get all joints in the active groups, including those from subgroups
active_joints = set()
def add_group_joints(group_name: str):
if group_name not in full_robot_model.supplemental_info.joint_groups:
raise ValueError(f"Unknown joint group: {group_name}")
group_info = full_robot_model.supplemental_info.joint_groups[group_name]
# Add direct joints
if "joints" in group_info:
active_joints.update(group_info["joints"])
# Add joints from subgroups
if "groups" in group_info:
for subgroup_name in group_info["groups"]:
add_group_joints(subgroup_name)
for group_name in active_group_names:
add_group_joints(group_name)
# Get all joints from the model
all_joints = set(full_robot_model.joint_names)
# The fixed joints are all joints minus the active joints
fixed_joints = list(all_joints - active_joints)
return cls(full_robot_model, fixed_joints, fixed_values)
def reduced_to_full_configuration(self, q_reduced: np.ndarray) -> np.ndarray:
"""
Convert a reduced configuration to the full configuration space.
:param q_reduced: Configuration in reduced space
:return: Configuration in full space with fixed joints set to their fixed values
"""
if q_reduced.shape[0] != self.num_dofs:
raise ValueError(
f"Expected q_reduced of length {self.num_dofs}, got {q_reduced.shape[0]} instead"
)
q_full = np.zeros(self.full_robot.num_dofs)
# Set active joints
for reduced_idx, full_idx in enumerate(self.reduced_to_full):
q_full[full_idx] = q_reduced[reduced_idx]
# Set fixed joints
for joint_name, value in zip(self.fixed_joints, self.fixed_values):
full_idx = self.full_robot.dof_index(joint_name)
q_full[full_idx] = value
return q_full
def full_to_reduced_configuration(self, q_full: np.ndarray) -> np.ndarray:
"""
Convert a full configuration to the reduced configuration space.
:param q_full: Configuration in full space
:return: Configuration in reduced space
"""
if q_full.shape[0] != self.full_robot.num_dofs:
raise ValueError(
f"Expected q_full of length {self.full_robot.num_dofs}, got {q_full.shape[0]} instead"
)
q_reduced = np.zeros(self.num_dofs)
# Copy active joints
for reduced_idx, full_idx in enumerate(self.reduced_to_full):
q_reduced[reduced_idx] = q_full[full_idx]
return q_reduced
def cache_forward_kinematics(self, q_reduced: np.ndarray, auto_clip=True) -> None:
"""
Perform forward kinematics using the reduced configuration.
:param q_reduced: Configuration in reduced space
"""
# First update the full robot's forward kinematics
q_full = self.reduced_to_full_configuration(q_reduced)
self.full_robot.cache_forward_kinematics(q_full, auto_clip)
# Then update the reduced model's forward kinematics
pin.framesForwardKinematics(
self.pinocchio_wrapper.model, self.pinocchio_wrapper.data, q_reduced
)
def clip_configuration(self, q_reduced: np.ndarray, margin: float = 1e-6) -> np.ndarray:
"""
Clip the reduced configuration to stay within joint limits with a small tolerance.
:param q_reduced: Configuration to clip
:param margin: Tolerance to keep away from joint limits
:return: Clipped configuration
"""
q_full = self.reduced_to_full_configuration(q_reduced)
q_full_clipped = self.full_robot.clip_configuration(q_full, margin)
return self.full_to_reduced_configuration(q_full_clipped)
def reset_forward_kinematics(self):
"""
Reset the forward kinematics to the initial configuration.
"""
# Reset full robot's forward kinematics
self.full_robot.reset_forward_kinematics()
# Reset reduced model's forward kinematics
self.cache_forward_kinematics(self.q_zero)
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