From aed4cfbd52b29b88b835c06a317df3020ed4d35c Mon Sep 17 00:00:00 2001
From: spirkelmann <simon.pirkelmann@gmail.com>
Date: Mon, 15 Jul 2019 23:04:23 +0200
Subject: [PATCH] initial commit for roboflut with a single robot

---
 roboflut/keyboard_controller.py |  43 ++++++++
 roboflut/roboflut.py            | 180 ++++++++++++++++++++++++++++++++
 2 files changed, 223 insertions(+)
 create mode 100644 roboflut/keyboard_controller.py
 create mode 100644 roboflut/roboflut.py

diff --git a/roboflut/keyboard_controller.py b/roboflut/keyboard_controller.py
new file mode 100644
index 0000000..cce35e6
--- /dev/null
+++ b/roboflut/keyboard_controller.py
@@ -0,0 +1,43 @@
+import socket
+import pygame
+
+pygame.init()
+pygame.display.set_mode((640, 480))
+
+rc_socket = socket.socket()
+try:
+    rc_socket.connect(('127.0.0.1', 1337)) # connect to robot
+except socket.error:
+    print("could not connect to socket")
+
+
+while True:
+    u1 = 0
+    u2 = 0
+    vmax = 10.0
+    events = pygame.event.get()
+    for event in events:
+        if event.type == pygame.KEYDOWN:
+            if event.key == pygame.K_LEFT:
+                u1 = -vmax / 10.0
+                u2 = vmax/ 10.0
+
+                print("turn left: ({},{})".format(u1, u2))
+            elif event.key == pygame.K_RIGHT:
+                u1 = vmax/ 10.0
+
+                u2 = -vmax/ 10.0
+
+                print("turn right: ({},{})".format(u1, u2))
+            elif event.key == pygame.K_UP:
+                u1 = vmax
+                u2 = vmax
+                print("forward: ({},{})".format(u1, u2))
+            elif event.key == pygame.K_DOWN:
+                u1 = -vmax 
+                u2 = -vmax 
+                print("backward: ({},{})".format(u1, u2))
+            rc_socket.send('({},{})\n'.format(u1, u2))
+        elif event.type == pygame.KEYUP:
+            print("key released, resetting: ({},{})".format(u1, u2))
+            rc_socket.send('({},{})\n'.format(u1, u2))
diff --git a/roboflut/roboflut.py b/roboflut/roboflut.py
new file mode 100644
index 0000000..1c240c4
--- /dev/null
+++ b/roboflut/roboflut.py
@@ -0,0 +1,180 @@
+import sys
+import socket
+import time
+import numpy as np
+
+import pygame
+
+from threading import Thread, Lock
+
+import scipy.integrate
+
+single_robot = True
+
+class Server:
+    def __init__(self):
+        self.ip = '127.0.0.1'
+        self.recv_port = 1337  # port for receiving data
+        self.send_port = 1338  # port for sending data
+        self.recv_addr = socket.getaddrinfo(self.ip, self.recv_port)[0][-1]
+
+        if not single_robot:
+            self.robots = []
+        else:
+            self.rob = Robot()
+
+        self.receiver = Thread(target=self.remote_control)
+        self.receiver.start()
+
+    def remote_control(self):
+        print("setting up socket communication ...")
+        recv_socket = socket.socket()
+        recv_socket.bind(self.recv_addr)
+        while True:
+            print("waiting for connections on {} ...".format(self.recv_addr))
+            recv_socket.listen(2)
+            (comm_socket, address) = recv_socket.accept() # this blocks until someone connects to the socket
+
+            print("starting thread for handling communication with {}".format(address))
+            Thread(target=self.handle_communication, args=(comm_socket, address)).start()
+
+    def handle_communication(self, socket, address):
+            print("connected!")
+            listening = True
+
+            if not single_robot:
+                rob = Robot()
+                self.robots.append(rob)
+
+            try:
+                while listening:
+                     # expected data: '(u1, u2)'\n"
+                     # where ui = control for motor i
+                     # ui \in [-1.0, 1.0]
+                    data = socket.recv(4096)
+                    data_str = data.decode()
+                    #print("Data received: {}".format(data_str))
+                    #print("processing data = {}".format(data_str))
+                    l = data_str.strip('()\n').split(',')
+                    #print("l = {}".format(l))
+                    u1 = float(l[0])
+                    #print("u1 = {}".format(u1))
+                    u2 = float(l[1])
+                    #print("u2 = {}".format(u2))
+
+                    if single_robot:
+                        self.rob.set_control(u1, u2)
+                    else:
+                        rob.set_control(u1, u2)
+            except ValueError:
+                print("ValueError: Data has wrong format.")
+                print("Data received: {}".format(data_str))
+            except IndexError:
+                print("IndexError: Data has wrong format.")
+                print("Data received: {}".format(data_str))
+            except Exception as e:
+                print("Some other error occured")
+                print("Exception: {}".format(e))
+            finally:
+                socket.close()
+                if not single_robot:
+                    self.robots.remove(rob)
+
+class Robot:
+    def __init__(self):
+        self.x = np.array([0.0, 0.0, 0.0])
+
+        self.u1 = 0.0
+        self.u2 = 0.0
+
+        self.r = 0.3
+        self.R = 0.5
+        self.d = 0.2
+
+        self.mutex = Lock()
+
+        self.omega_max = 50.0
+
+        self.integrator = scipy.integrate.ode(self.f)
+        self.integrator.set_integrator('dopri5')
+
+        self.simulator = Thread(target=self.simulate)
+        self.simulator.start()
+
+    def set_control(self, u1, u2):
+        self.mutex.acquire()
+        try:
+            self.u1 = u1
+            self.u2 = u2
+        finally:
+            self.mutex.release()
+
+    def simulate(self):
+        t0 = time.time()
+        t = time.time()-t0
+
+        while True:
+            self.mutex.acquire()
+            try:
+                self.integrator.set_f_params(self.omega_max * np.array([self.u1, self.u2]))
+            finally:
+                self.mutex.release()
+            self.integrator.set_initial_value(self.x, t)
+
+            dt = time.time() - t0 - t
+
+            self.x = self.integrator.integrate(self.integrator.t + dt)
+            t = time.time() - t0
+
+    def f(self, t, x, u):
+        r = self.r
+        d = self.d
+        R = self.R
+
+        theta = x[2]
+        omegar = u[0]
+        omegal = u[1]
+
+        dx = np.zeros((3,1))
+        dx[0] = (r/2.0 * np.cos(theta) - r * d/(2.0 * R) * np.sin(theta)) * omegar + \
+                (r/2.0 * np.cos(theta) + r * d/(2.0 * R) * np.sin(theta)) * omegal
+        dx[1] = (r/2.0 * np.sin(theta) + r * d/(2.0 * R) * np.cos(theta)) * omegar + \
+                (r/2.0 * np.sin(theta) - r * d/(2.0 * R) * np.cos(theta)) * omegal
+        dx[2] = r/(2.0 * R) * (omegar - omegal)
+
+        return dx
+
+def main(args):
+    # wait for connections of socket
+    s = Server()
+
+    background_colour = (255, 255, 255)
+    (width, height) = (640, 480)
+    screen = pygame.display.set_mode((width, height))
+    pygame.display.set_caption('Roboflut')
+    screen.fill(background_colour)
+    pygame.display.flip()
+
+    running = True
+    while running:
+        r = s.rob
+        #for r in s.robots:
+        x = int(r.x[0] + width/2.0)
+        y = int(r.x[1] + height / 2.0)
+        phi = r.x[2]
+        phases = ( phi + np.pi) % (2 * np.pi ) - np.pi
+
+        if x < 0 or x > width or y < 0 or y > height:
+            r.x[0] = 0.0
+            r.x[1] = 0.0
+        c = int((phases + 2.0 * np.pi) / (4.0 * np.pi) * 255)
+        #color = (c, c, c)
+        color = (0,0,0)
+
+        screen.set_at((x, y), color)
+
+        pygame.display.flip()
+
+
+if __name__ == '__main__':
+    main(sys.argv)
\ No newline at end of file