Files
PathPlanning/Search-based Planning/Search_3D/RTA_Astar3D.py
T
2020-07-13 23:29:54 -07:00

75 lines
2.4 KiB
Python

# this is the three dimensional Real-time Adaptive LRTA* algo
# !/usr/bin/env python3
# -*- coding: utf-8 -*-
"""
@author: yue qi
"""
import numpy as np
import matplotlib.pyplot as plt
import os
import sys
sys.path.append(os.path.dirname(os.path.abspath(__file__)) + "/../../Search-based Planning/")
from Search_3D.env3D import env
from Search_3D import Astar3D
from Search_3D.utils3D import getDist, getRay, g_Space, Heuristic, getNearest, isCollide, \
cost, obstacleFree, children
from Search_3D.plot_util3D import visualization
import queue
class RTA_A_star:
def __init__(self, resolution=0.5, N=7):
self.N = N # node to expand
self.Astar = Astar3D.Weighted_A_star(resolution=resolution) # initialize A star
self.path = [] # empty path
self.st = []
self.localhvals = []
def updateHeuristic(self):
# Initialize hvalues at infinity
self.localhvals = []
nodeset, vals = [], []
for (_,_,xi) in self.Astar.OPEN.enumerate():
nodeset.append(xi)
vals.append(self.Astar.g[xi] + self.Astar.h[xi])
j, fj = nodeset[np.argmin(vals)], min(vals)
self.st = j
# single pass update of hvals
for xi in self.Astar.CLOSED:
self.Astar.h[xi] = fj - self.Astar.g[xi]
self.localhvals.append(self.Astar.h[xi])
def move(self):
st, localhvals = self.st, self.localhvals
maxhval = max(localhvals)
sthval = self.Astar.h[st]
# find the lowest path up hill
while sthval < maxhval:
parentsvals , parents = [] , []
# find the max child
for xi in children(self.Astar,st):
if xi in self.Astar.CLOSED:
parents.append(xi)
parentsvals.append(self.Astar.h[xi])
lastst = st
st = parents[np.argmax(parentsvals)]
self.path.append([st,lastst]) # add to path
sthval = self.Astar.h[st]
self.Astar.reset(self.st)
def run(self):
while True:
if self.Astar.run(N=self.N):
self.Astar.Path = self.Astar.Path + self.path
self.Astar.done = True
visualization(self.Astar)
plt.show()
break
self.updateHeuristic()
self.move()
if __name__ == '__main__':
T = RTA_A_star(resolution=1, N=100)
T.run()