mirror of
https://github.com/zhm-real/PathPlanning.git
synced 2026-08-30 00:50:46 +08:00
zhm-real
173 lines
4.2 KiB
Python
173 lines
4.2 KiB
Python
"""
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Potential_Field
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@author: huiming zhou
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"""
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import os
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import sys
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import numpy as np
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import matplotlib.pyplot as plt
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from collections import deque
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sys.path.append(os.path.dirname(os.path.abspath(__file__)) +
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"/../../Search_based_Planning/")
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from Search_2D import plotting
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from Search_2D import env
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class PF:
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def __init__(self, s_start, s_goal):
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self.s_start = s_start
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self.s_goal = s_goal
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self.kp = 5.0
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self.eta = 400
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self.r = 30.0
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self.OL = 10
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self.rr = 2
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self.Env = env.Env()
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self.Plot = plotting.Plotting(s_start, s_goal)
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self.u_set = self.Env.motions # feasible input set
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self.obs = self.Env.obs # position of obstacles
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self.x = self.Env.x_range
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self.y = self.Env.y_range
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def run(self):
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pmap, minx, miny = self.calc_potential_field()
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d = np.hypot(self.s_start[0] - self.s_goal[0],
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self.s_start[1] - self.s_goal[1])
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ix = self.s_start[0] - minx
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iy = self.s_start[1] - miny
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gix = self.s_goal[0] - minx
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giy = self.s_goal[1] - miny
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self.draw_heatmap(pmap)
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plt.gcf().canvas.mpl_connect('key_release_event',
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lambda event: [exit(0) if event.key == 'escape' else None])
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plt.plot(ix, iy, "sk")
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plt.plot(gix, giy, "sm")
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rx, ry = [self.s_start[0]], [self.s_goal[0]]
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ids_rec = deque()
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while d >= 1:
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minp = float("inf")
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minix, miniy = -1, -1
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for u in self.u_set:
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inx = int(ix + u[0])
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iny = int(iy + u[1])
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if inx >= len(pmap) or iny >= len(pmap[0]) or inx < 0 or iny < 0:
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p = float("inf")
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print("test")
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else:
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p = pmap[inx][iny]
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if minp > p:
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minp = p
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minix = inx
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miniy = iny
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ix = minix
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iy = miniy
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xp = ix + minx
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yp = iy + miny
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d = np.hypot(self.s_goal[0] - xp, self.s_goal[1] - yp)
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rx.append(xp)
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ry.append(yp)
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if self.is_oscillation(ids_rec, ix, iy):
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print("Oscillation detected at ({},{})!".format(ix, iy))
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break
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plt.plot(ix, iy, ".r")
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plt.pause(0.01)
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return rx, ry
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def calc_potential_field(self):
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minx = 0
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miny = 0
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maxx = self.x - 1
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maxy = self.y - 1
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xw = maxx - minx
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yw = maxy - miny
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pmap = [[0.0 for i in range(yw)] for i in range(xw)]
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for ix in range(xw):
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x = ix + minx
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for iy in range(yw):
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y = iy + miny
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ug = self.calc_attractive_potential(x, y)
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uo = self.calc_repulsive_potential(x, y)
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uf = ug + uo
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pmap[ix][iy] = uf
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return pmap, minx, miny
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def calc_attractive_potential(self, x, y):
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return 0.5 * self.kp * \
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np.hypot(x - self.s_goal[0], y - self.s_goal[1])
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def calc_repulsive_potential(self, x, y):
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dmin = float("inf")
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for s in self.obs:
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d = np.hypot(x - s[0], y - s[1])
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if dmin >= d:
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dmin = d
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# calc repulsive potential
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dq = dmin
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if dq <= self.rr:
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if dq <= 0.8:
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dq = 0.8
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return 0.5 * self.eta * (1.0 / dq - 1.0 / self.rr) ** 2
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else:
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return 0.0
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def is_oscillation(self, ids_rec, ix, iy):
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ids_rec.append((ix, iy))
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if len(ids_rec) > self.OL:
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ids_rec.popleft()
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ids_set = set()
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for s in ids_rec:
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if s in ids_set:
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return True
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else:
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ids_set.add(s)
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return False
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@staticmethod
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def draw_heatmap(data):
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data = np.array(data).T
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plt.pcolor(data, vmax=100.0, cmap=plt.cm.Blues)
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def main():
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s_start = (5, 5)
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s_goal = (45, 25)
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pf = PF(s_start, s_goal)
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plt.grid(True)
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plt.axis("equal")
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_, _ = pf.run()
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plt.show()
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if __name__ == '__main__':
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print(__file__ + " start!!")
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main()
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