Multi-Segment Cartesian Motion Complete Example

This example shows how to combine one move_point segment and one move_line segment with move_sequence(): lift the left end effector 3 cm in the base frame, make a small tool-frame displacement, and return to the start. Targets are generated from the current end-effector pose plus bounded offsets; positions are in meters and quaternions use xyzw order.

Related states: JointStand, upper_body_tele_task

Related APIs: create_move_sequence_builder(), seq.add_move_point(), seq.add_move_line(), move_sequence()

Python

import math
import os
import time

os.environ.setdefault("FASTDDS_BUILTIN_TRANSPORTS", "UDPv4")  # required on the robot

from fourier_aurora_client import AuroraClient
from movetools_session import MoveToolsSession

Z_OFFSET = 0.03                # base-frame lift (m)
TOOL_DELTA = [0.0, 0.0, 0.02]  # tool-frame small displacement (m)


def wait_fsm(client, expected, timeout_s=8.0):
    deadline = time.monotonic() + timeout_s
    while client.get_fsm_state() != expected:
        if time.monotonic() >= deadline:
            raise RuntimeError(f"state {expected} not reached")
        time.sleep(0.05)


def check_result(result, name):
    if not result.success:
        raise RuntimeError(f"{name} failed: {result.code} {result.message}")


def normalized_pose(pose):
    pose = list(pose)
    norm = math.sqrt(sum(q * q for q in pose[3:]))
    return pose[:3] + [q / norm for q in pose[3:]]


client = AuroraClient.get_instance(
    domain_id=123,  # Must match the DDS domain used by the running AuroraCore
    robot_name="grw",
)
movetools = MoveToolsSession(client, robot_name="grw")
started = False

try:
    input("Press Enter to switch to JointStand...")
    client.set_fsm_state(1)
    wait_fsm(client, 1)
    time.sleep(2.0)

    input("Press Enter to switch to upper_body_tele_task...")
    client.set_fsm_state(4)
    wait_fsm(client, 4)
    time.sleep(1.0)

    movetools.start()
    started = True

    start_pose = normalized_pose(client.get_cartesian_state("left_manipulator", "pose"))
    print(f"start pose: {[round(v, 4) for v in start_pose]}")

    up_pose = start_pose[:2] + [start_pose[2] + Z_OFFSET] + start_pose[3:]

    seq = movetools.create_move_sequence_builder(groups=["left_manipulator"])

    # Segment 1: base-frame point-to-point lift of 3 cm
    seq.add_move_point(
        {"left_end_effector_link": up_pose},
        expect_vel=150,
        frame="base",
    )
    # Segment 2: tool-frame straight-line displacement
    seq.add_move_line(
        {"left_end_effector_link": TOOL_DELTA + [0.0, 0.0, 0.0, 1.0]},
        expect_vel=120,
        frame="tool",
    )
    # Segment 3: return to the start pose
    seq.add_move_point(
        {"left_end_effector_link": start_pose},
        expect_vel=150,
        frame="base",
    )

    input("Press Enter to run move_sequence...")
    result = movetools.move_sequence(seq)
    check_result(result, "move_sequence")

    movetools.wait_until_idle()
    movetools.raise_if_error()

    end_pose = normalized_pose(client.get_cartesian_state("left_manipulator", "pose"))
    print(f"restored z delta: {round(end_pose[2] - start_pose[2], 4)}")
    print("move_sequence complete")

finally:
    if started:
        movetools.stop()
    if client.get_fsm_state() != 3:
        client.set_fsm_state(3)   # back to the standing policy state
        wait_fsm(client, 3)
    client.close()