metrics.py

#! /usr/bin/env python3
# Copyright 2022 Joshua Wallace
#
# 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 glob
import math
import os
import pickle
from random import randint, seed, uniform
import time
 
from geometry_msgs.msg import PoseStamped
from nav2_simple_commander.robot_navigator import BasicNavigator
import numpy as np
from numpy.typing import NDArray
import rclpy
from rclpy.time import Time
from transforms3d.euler import euler2quat
 
 
def getPlannerResults(
        navigator: BasicNavigator, initial_pose: PoseStamped,
        goal_pose: PoseStamped, planners: list[str]) -> list[PoseStamped]:
    results = []
    for planner in planners:
        path = navigator._getPathImpl(initial_pose, goal_pose, planner, use_start=True)
        if path is not None and path.error_code == 0:
            results.append(path)
        else:
            print(planner, 'planner failed to produce the path')
            return results
    return results
 
 
def getRandomStart(
        costmap: NDArray[np.float32], max_cost: int,
        side_buffer: int, time_stamp: Time, res: float) -> PoseStamped:
    start = PoseStamped()
    start.header.frame_id = 'map'
    start.header.stamp = time_stamp
    while True:
        row = randint(side_buffer, costmap.shape[0] - side_buffer)
        col = randint(side_buffer, costmap.shape[1] - side_buffer)
 
        if costmap[row, col] < max_cost:
            start.pose.position.x = col * res
            start.pose.position.y = row * res
 
            yaw = uniform(0, 1) * 2 * math.pi
            quad = euler2quat(0.0, 0.0, yaw)
            start.pose.orientation.w = quad[0]
            start.pose.orientation.x = quad[1]
            start.pose.orientation.y = quad[2]
            start.pose.orientation.z = quad[3]
            break
    return start
 
 
def getRandomGoal(
        costmap: NDArray[np.float32], start: PoseStamped,
        max_cost: int, side_buffer: int, time_stamp: Time, res: float) -> PoseStamped:
    goal = PoseStamped()
    goal.header.frame_id = 'map'
    goal.header.stamp = time_stamp
    while True:
        row = randint(side_buffer, costmap.shape[0] - side_buffer)
        col = randint(side_buffer, costmap.shape[1] - side_buffer)
 
        start_x = start.pose.position.x
        start_y = start.pose.position.y
        goal_x = col * res
        goal_y = row * res
        x_diff = goal_x - start_x
        y_diff = goal_y - start_y
        dist = math.sqrt(x_diff ** 2 + y_diff ** 2)
 
        if costmap[row, col] < max_cost and dist > 3.0:
            goal.pose.position.x = goal_x
            goal.pose.position.y = goal_y
 
            yaw = uniform(0, 1) * 2 * math.pi
            quad = euler2quat(0.0, 0.0, yaw)
            goal.pose.orientation.w = quad[0]
            goal.pose.orientation.x = quad[1]
            goal.pose.orientation.y = quad[2]
            goal.pose.orientation.z = quad[3]
            break
    return goal
 
 
def main() -> None:
    rclpy.init()
 
    navigator = BasicNavigator()
 
    # Set map to use, other options: 100by100_15, 100by100_10
    map_path = os.getcwd() + '/' + glob.glob('**/100by100_20.yaml', recursive=True)[0]
    navigator.changeMap(map_path)
    time.sleep(2)
 
    # Get the costmap for start/goal validation
    costmap_msg = navigator.getGlobalCostmap()
    costmap = np.asarray(costmap_msg.data)
    costmap.resize(costmap_msg.metadata.size_y, costmap_msg.metadata.size_x)
 
    planners = ['Navfn', 'ThetaStar', 'SmacHybrid', 'Smac2d', 'SmacLattice']
    max_cost = 210
    side_buffer = 100
    time_stamp = navigator.get_clock().now().to_msg()
    results: list[PoseStamped] = []
    seed(33)
 
    random_pairs = 100
    res = costmap_msg.metadata.resolution
    i = 0
    while len(results) != random_pairs:
        print('Cycle: ', i, 'out of: ', random_pairs)
        start = getRandomStart(costmap, max_cost, side_buffer, time_stamp, res)
        goal = getRandomGoal(costmap, start, max_cost, side_buffer, time_stamp, res)
        print('Start', start)
        print('Goal', goal)
        result = getPlannerResults(navigator, start, goal, planners)
        if len(result) == len(planners):
            results.append(result)
            i = i + 1
        else:
            print('One of the planners was invalid')
 
    print('Write Results...')
    with open(os.getcwd() + '/results.pickle', 'wb+') as f:
        pickle.dump(results, f, pickle.HIGHEST_PROTOCOL)
 
    with open(os.getcwd() + '/costmap.pickle', 'wb+') as f:
        pickle.dump(costmap_msg, f, pickle.HIGHEST_PROTOCOL)
 
    with open(os.getcwd() + '/planners.pickle', 'wb+') as f:
        pickle.dump(planners, f, pickle.HIGHEST_PROTOCOL)
    print('Write Complete')
    exit(0)
 
 
if __name__ == '__main__':
    main()