lerobot/lerobot/common/robots/lekiwi/lekiwi_robot.py

356 lines
14 KiB
Python

#!/usr/bin/env python
# Copyright 2024 The HuggingFace Inc. team. All rights reserved.
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
# http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.
import base64
import json
import logging
import threading
import time
import cv2
import numpy as np
import zmq
from lerobot.common.cameras.utils import make_cameras_from_configs
from lerobot.common.constants import OBS_IMAGES, OBS_STATE
from lerobot.common.errors import DeviceAlreadyConnectedError, DeviceNotConnectedError
from lerobot.common.motors.feetech import (
FeetechMotorsBus,
TorqueMode,
run_full_arm_calibration,
)
from ..robot import Robot
from ..utils import ensure_safe_goal_position
from .configuration_lekiwi import LeKiwiRobotConfig
class LeKiwiRobot(Robot):
"""
The robot includes a three omniwheel mobile base and a remote follower arm.
The leader arm is connected locally (on the laptop) and its joint positions are recorded and then
forwarded to the remote follower arm (after applying a safety clamp).
In parallel, keyboard teleoperation is used to generate raw velocity commands for the wheels.
"""
config_class = LeKiwiRobotConfig
name = "lekiwi"
def __init__(self, config: LeKiwiRobotConfig):
super().__init__(config)
self.config = config
self.id = config.id
self.port_zmq_cmd = config.port_zmq_cmd
self.port_zmq_observations = config.port_zmq_observations
# TODO(Steven): Consider in the future using S100 robot class
# TODO(Steven): Another option is to use the motorbus factory, but in this case we assume that
# what we consider 'lekiwi robot' always uses the FeetechMotorsBus
# TODO(Steven): Order and dimension are generally assumed to be 6 first for arm, 3 last for base
self.actuators_bus = FeetechMotorsBus(
port=self.config.port_motor_bus,
motors={
"arm_shoulder_pan": config.shoulder_pan,
"arm_shoulder_lift": config.shoulder_lift,
"arm_elbow_flex": config.elbow_flex,
"arm_wrist_flex": config.wrist_flex,
"arm_wrist_roll": config.wrist_roll,
"arm_gripper": config.gripper,
"base_left_wheel": config.left_wheel,
"base_right_wheel": config.right_wheel,
"base_back_wheel": config.back_wheel,
},
)
self.arm_actuators = [m for m in self.actuators_bus.motor_names if m.startswith("arm")]
self.base_actuators = [m for m in self.actuators_bus.motor_names if m.startswith("base")]
self.max_relative_target = config.max_relative_target
# TODO(Steven): Consider removing cameras from configs
self.cameras = make_cameras_from_configs(config.cameras)
self.observation_lock = threading.Lock()
self.last_observation = None
self.zmq_context = None
self.zmq_cmd_socket = None
self.zmq_observation_socket = None
self.is_connected = False
self.logs = {}
@property
def state_feature(self) -> dict:
return {
"dtype": "float32",
"shape": (len(self.actuators_bus),),
"names": {"motors": list(self.actuators_bus.motors)},
}
@property
def action_feature(self) -> dict:
return self.state_feature
@property
def camera_features(self) -> dict[str, dict]:
cam_ft = {}
for cam_key, cam in self.cameras.items():
cam_ft[cam_key] = {
"shape": (cam.height, cam.width, cam.channels),
"names": ["height", "width", "channels"],
"info": None,
}
return cam_ft
def setup_zmq_sockets(self):
context = zmq.Context()
cmd_socket = context.socket(zmq.PULL)
cmd_socket.setsockopt(zmq.CONFLATE, 1)
cmd_socket.bind(f"tcp://*:{self.port_zmq_cmd}")
observation_socket = context.socket(zmq.PUSH)
observation_socket.setsockopt(zmq.CONFLATE, 1)
observation_socket.bind(f"tcp://*:{self.port_zmq_observations}")
return context, cmd_socket, observation_socket
def setup_actuators(self):
# Set-up arm actuators (position mode)
# We assume that at connection time, arm is in a rest position,
# and torque can be safely disabled to run calibration.
self.actuators_bus.write("Torque_Enable", TorqueMode.DISABLED.value, self.arm_actuators)
self.calibrate() # TODO(Steven): This should be only for the arm
# Mode=0 for Position Control
self.actuators_bus.write("Mode", 0, self.arm_actuators)
# Set P_Coefficient to lower value to avoid shakiness (Default is 32)
self.actuators_bus.write("P_Coefficient", 16, self.arm_actuators)
# Set I_Coefficient and D_Coefficient to default value 0 and 32
self.actuators_bus.write("I_Coefficient", 0, self.arm_actuators)
self.actuators_bus.write("D_Coefficient", 32, self.arm_actuators)
# Close the write lock so that Maximum_Acceleration gets written to EPROM address,
# which is mandatory for Maximum_Acceleration to take effect after rebooting.
self.actuators_bus.write("Lock", 0, self.arm_actuators)
# Set Maximum_Acceleration to 254 to speedup acceleration and deceleration of
# the motors. Note: this configuration is not in the official STS3215 Memory Table
self.actuators_bus.write("Maximum_Acceleration", 254, self.arm_actuators)
self.actuators_bus.write("Acceleration", 254, self.arm_actuators)
logging.info("Activating torque.")
self.actuators_bus.write("Torque_Enable", TorqueMode.ENABLED.value, self.arm_actuators)
# Check arm can be read
self.actuators_bus.read("Present_Position", self.arm_actuators)
# Set-up base actuators (velocity mode)
self.actuators_bus.write("Lock", 0, self.base_actuators)
self.actuators_bus.write("Mode", [1, 1, 1], self.base_actuators)
self.actuators_bus.write("Lock", 1, self.base_actuators)
def connect(self) -> None:
if self.is_connected:
raise DeviceAlreadyConnectedError(
"LeKiwi Robot is already connected. Do not run `robot.connect()` twice."
)
logging.info("Connecting actuators.")
self.actuators_bus.connect()
self.setup_actuators()
logging.info("Connecting cameras.")
for cam in self.cameras.values():
cam.connect()
logging.info("Connecting ZMQ sockets.")
self.zmq_context, self.zmq_cmd_socket, self.zmq_observation_socket = self.setup_zmq_sockets()
self.is_connected = True
def calibrate(self) -> None:
# Copied from S100 robot
"""After calibration all motors function in human interpretable ranges.
Rotations are expressed in degrees in nominal range of [-180, 180],
and linear motions (like gripper of Aloha) in nominal range of [0, 100].
"""
actuators_calib_path = self.calibration_dir / f"{self.config.id}.json"
if actuators_calib_path.exists():
with open(actuators_calib_path,encoding="utf-8") as f:
calibration = json.load(f)
else:
logging.info("Missing calibration file '%s'",actuators_calib_path)
calibration = run_full_arm_calibration(
self.actuators_bus, self.robot_type, self.name, "follower"
)
logging.info("Calibration is done! Saving calibration file '%s'",actuators_calib_path)
actuators_calib_path.parent.mkdir(parents=True, exist_ok=True)
with open(actuators_calib_path, "w",encoding="utf-8") as f:
json.dump(calibration, f)
self.actuators_bus.set_calibration(calibration)
def get_observation(self) -> dict[str, np.ndarray]:
"""The returned observations do not have a batch dimension."""
if not self.is_connected:
raise DeviceNotConnectedError("LeKiwiRobot is not connected. You need to run `robot.connect()`.")
obs_dict = {}
# Read actuators position for arm and vel for base
before_read_t = time.perf_counter()
obs_dict[OBS_STATE] = self.actuators_bus.read(
"Present_Position", self.arm_actuators
) + self.actuators_bus.read("Present_Speed", self.base_actuators)
self.logs["read_pos_dt_s"] = time.perf_counter() - before_read_t
# Capture images from cameras
for cam_key, cam in self.cameras.items():
before_camread_t = time.perf_counter()
frame = cam.async_read()
ret, buffer = cv2.imencode(".jpg", frame, [int(cv2.IMWRITE_JPEG_QUALITY), 90])
if ret:
obs_dict[f"{OBS_IMAGES}.{cam_key}"] = base64.b64encode(buffer).decode("utf-8")
else:
obs_dict[f"{OBS_IMAGES}.{cam_key}"] = ""
self.logs[f"read_camera_{cam_key}_dt_s"] = cam.logs["delta_timestamp_s"]
self.logs[f"async_read_camera_{cam_key}_dt_s"] = time.perf_counter() - before_camread_t
return obs_dict
def send_action(self, action: np.ndarray) -> np.ndarray:
# Copied from S100 robot
"""Command lekiwi to move to a target joint configuration.
The relative action magnitude may be clipped depending on the configuration parameter
`max_relative_target`. In this case, the action sent differs from original action.
Thus, this function always returns the action actually sent.
Args:
action (np.ndarray): array containing the goal positions for the motors.
Raises:
RobotDeviceNotConnectedError: if robot is not connected.
Returns:
np.ndarray: the action sent to the motors, potentially clipped.
"""
if not self.is_connected:
raise DeviceNotConnectedError("LeKiwiRobot is not connected. You need to run `robot.connect()`.")
# Input action is in motor space
goal_pos = action
# Cap goal position when too far away from present position.
# /!\ Slower fps expected due to reading from the follower.
if self.config.max_relative_target is not None:
present_pos = self.actuators_bus.read("Present_Position", self.arm_actuators)
goal_pos[:6] = ensure_safe_goal_position(
goal_pos[:6], present_pos, self.config.max_relative_target
)
# Send goal position to the actuators
# TODO(Steven): This happens synchronously
self.actuators_bus.write("Goal_Position", goal_pos[:6].astype(np.int32), self.arm_actuators)
self.actuators_bus.write("Goal_Speed", goal_pos[6:].astype(np.int32), self.base_actuators)
return goal_pos
def update_last_observation(self, stop_event):
while not stop_event.is_set():
obs = self.get_observation()
with self.observation_lock:
self.last_observation = obs
# TODO(Steven): Consider adding a delay to not starve the CPU
def stop(self):
# TODO(Steven): Assumes there's only 3 motors for base
logging.info("Stopping base")
self.actuators_bus.write("Goal_Speed", [0, 0, 0], self.base_actuators)
logging.info("Base motors stopped")
def run(self):
# Copied logic from run_lekiwi in lekiwi_remote.py
if not self.is_connected:
raise DeviceNotConnectedError("LeKiwiRobot is not connected. You need to run `robot.connect()`.")
stop_event = threading.Event()
observation_thread = threading.Thread(
target=self.update_last_observation, args=(stop_event), daemon=True
)
observation_thread.start()
last_cmd_time = time.time()
logging.info("LeKiwi robot server started. Waiting for commands...")
try:
while True:
loop_start_time = time.time()
try:
msg = self.cmd_socket.recv_string(zmq.NOBLOCK)
data = json.loads(msg)
self.send_action(data)
last_cmd_time = time.time()
# except zmq.Again:
# logging.warning("ZMQ again")
except Exception as e:
logging.error("Message fetching failed: %s",e)
# Watchdog: stop the robot if no command is received for over 0.5 seconds.
now = time.time()
if now - last_cmd_time > 0.5:
self.stop()
with self.observation_lock:
self.zmq_observation_socket.send_string(json.dumps(self.last_observation))
# Ensure a short sleep to avoid overloading the CPU.
elapsed = time.time() - loop_start_time
time.sleep(
max(0.033 - elapsed, 0)
) # If robot jitters increase the sleep and monitor cpu load with `top` in cmd
except KeyboardInterrupt:
print("Shutting down LeKiwi server.")
finally:
stop_event.set()
observation_thread.join()
self.disconnect()
def print_logs(self):
# TODO(Steven): Refactor logger
pass
def disconnect(self):
if not self.is_connected:
raise DeviceNotConnectedError(
"LeKiwi is not connected. You need to run `robot.connect()` before disconnecting."
)
self.stop()
self.actuators_bus.disconnect()
for cam in self.cameras.values():
cam.disconnect()
self.observation_socket.close()
self.cmd_socket.close()
self.context.term()
self.is_connected = False
def __del__(self):
if getattr(self, "is_connected", False):
self.disconnect()