Drone Search

drone_search.py

# Create your search Drone
## Create a class for a drone which can move in a 2D space within fixed boundaries
## The drones perform random walk
## There are 2 targets on the ground that we want to track
## Deploy 2 drones and stop if both targets are found

# create a 2D grid space of size L x L, L = 50 (create this in your mind)
L = 50
# Create two tuples for each target, specifying the x and y coordinates,
# 0 < x < L, 0 < y < L
t1 = tuple(np.random.uniform(0, L, (1,2))[0])
t2 = tuple(np.random.uniform(0, L, (1,2))[0])
targets = [t1, t2]


# create a class for a Drone with attributes: x, y, speed, range
# and a function called: update_position()
class Drone:
  def __init__(self, x,y, speed, rng):
    self.x = x
    self.y = y
    self.speed = speed
    self.rng = rng

  def update_position(self):
    self.x += self.speed*np.random.uniform(-1,1)
    self.y += self.speed*np.random.uniform(-1,1)

    m = 10

    # make sure that: 0 < self.x < L and 0 < self.y < L
    # HINT: Use if-else
    # If it is < 0, make it m
    # If it is > L, make it L - m
    # m = 10
    if self.x < 0:
      self.x = m
    elif self.x > L:
      self.x = L - m

    if self.y < 0:
      self.y = m
    elif self.y > L:
      self.y = L - m

  def find_target(self):
    # (self.x, self.y) <---> target's (x,y)
    for target in targets:
      distance = np.sqrt( (self.x - target[0])**2 + (self.y - target[1])**2 )
      if distance < self.rng:
        print('target found at {}'.format(target))
        targets.remove(target)

# Assignment
# [] print when a new target is found, and stop when all targets are found
# [] plot the trajectory for each drone


# Run a loop for time-steps

drone_list = []
drone_list.append(Drone(np.random.uniform(0,L),
                        np.random.uniform(0,L),
                        np.random.uniform(5,10),
                        10.0 ))


drone_list.append(Drone(np.random.uniform(0,L),
                        np.random.uniform(0,L),
                        np.random.uniform(5,10),
                        10.0 ))

# Dictionaries to save the trajectory of each drone
X = {}
Y = {}
for i, drone in enumerate(drone_list):
  X[i] = []
  Y[i] = []

# Time-loop
T = 500
for t in range(T):
  for i, drone in enumerate(drone_list):
    drone.update_position()
    drone.find_target()
    X[i].append(drone.x)
    Y[i].append(drone.y)

  # found all targets
  if len(targets) == 0:
    break
    
plt.figure()
for i in range(len(drone_list)):
  plt.plot(X[i], Y[i], 'x-', label='drone #{}'.format(i))
plt.legend()
plt.xlim([0,L])
plt.ylim([0,L])
plt.xlabel('x-coordinate')
plt.ylabel('y-coordinate')
plt.title('Drone Trajectory')