open source driving agent
You can not select more than 25 topics Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.

64 lines
2.4 KiB

import selfdrive.messaging as messaging
import numpy as np
X_PATH = np.arange(0.0, 50.0)
def model_polyfit(points):
return np.polyfit(X_PATH, map(float, points), 3)
# lane width http://safety.fhwa.dot.gov/geometric/pubs/mitigationstrategies/chapter3/3_lanewidth.cfm
_LANE_WIDTH_V = np.asarray([3., 3.8])
# break points of speed
_LANE_WIDTH_BP = np.asarray([0., 31.])
def calc_desired_path(l_poly, r_poly, p_poly, l_prob, r_prob, p_prob, speed):
#*** this function computes the poly for the center of the lane, averaging left and right polys
lane_width = np.interp(speed, _LANE_WIDTH_BP, _LANE_WIDTH_V)
# lanes in US are ~3.6m wide
half_lane_poly = np.array([0., 0., 0., lane_width / 2.])
if l_prob + r_prob > 0.01:
c_poly = ((l_poly - half_lane_poly) * l_prob +
(r_poly + half_lane_poly) * r_prob) / (l_prob + r_prob)
c_prob = np.sqrt((l_prob**2 + r_prob**2) / 2.)
else:
c_poly = np.zeros(4)
c_prob = 0.
p_weight = 1. # predicted path weight relatively to the center of the lane
d_poly = list((c_poly*c_prob + p_poly*p_prob*p_weight ) / (c_prob + p_prob*p_weight))
return d_poly, c_poly, c_prob
class PathPlanner(object):
def __init__(self, model):
self.model = model
self.dead = True
self.d_poly = [0., 0., 0., 0.]
self.last_model = 0.
self.logMonoTime = 0
self.lead_dist, self.lead_prob, self.lead_var = 0, 0, 1
def update(self, cur_time, v_ego):
md = messaging.recv_sock(self.model)
if md is not None:
self.logMonoTime = md.logMonoTime
p_poly = model_polyfit(md.model.path.points) # predicted path
p_prob = 1. # model does not tell this probability yet, so set to 1 for now
l_poly = model_polyfit(md.model.leftLane.points) # left line
l_prob = md.model.leftLane.prob # left line prob
r_poly = model_polyfit(md.model.rightLane.points) # right line
r_prob = md.model.rightLane.prob # right line prob
self.lead_dist = md.model.lead.dist
self.lead_prob = md.model.lead.prob
self.lead_var = md.model.lead.std**2
#*** compute target path ***
self.d_poly, _, _ = calc_desired_path(l_poly, r_poly, p_poly, l_prob, r_prob, p_prob, v_ego)
self.last_model = cur_time
self.dead = False
elif cur_time - self.last_model > 0.5:
self.dead = True