Pose Velocity Acceleration (PVA) Sensor

A Pva reads the ground-truth kinematic state of a frame. Use it for privileged observations, state estimation, or control inputs that require more than an inertial sensor measures. Use an Inertial Measurement Unit (IMU) when the observation should follow accelerometer and gyroscope conventions.

The sensor can attach directly to a rigid body or to a fixed child prim beneath a rigid-body ancestor. In the latter case, Isaac Lab composes the child’s fixed transform with the configured sensor offset.

Measurement contract

For E environments, every vector has shape (E, 3). The pose has shape (E, 7) in (x, y, z, qx, qy, qz, qw) order.

Buffer	Frame and units	Meaning
pose_w	World; [m, unitless]	Sensor position and orientation
projected_gravity_b	Sensor; unitless	Unit gravity direction projected into the sensor frame
lin_vel_b	Sensor; [m/s]	Linear velocity relative to the world
ang_vel_b	Sensor; [rad/s]	Angular velocity relative to the world
lin_acc_b	Sensor; [m/s²]	Coordinate linear acceleration; zero at rest and \(-g\) in free fall
ang_acc_b	Sensor; [rad/s²]	Angular acceleration relative to the world

Configure and read the sensor

from isaaclab.sensors import PvaCfg

base_state = PvaCfg(
    prim_path="{ENV_REGEX_NS}/Robot/base",
    update_period=0.0,
    offset=PvaCfg.OffsetCfg(pos=(0.0, 0.0, 0.05)),
)

The data fields are ProxyArray buffers. Convert them to Torch views only where Torch operations are required:

pva_data = scene["base_state"].data
pose_w = pva_data.pose_w.torch
linear_velocity = pva_data.lin_vel_b.torch
coordinate_acceleration = pva_data.lin_acc_b.torch

Like the IMU, acceleration uses state from consecutive simulation updates. Reset the scene and sensor state together at episode boundaries.

A complete runnable example is available in scripts/demos/sensors/pva_sensor.py:

uv run --extra isaacsim python scripts/demos/sensors/pva_sensor.py