Improve simple control algorithm and add drawing and mouse control

remote_control/simple_control.py

@@ -0,0 +1,217 @@
+import socket
+import pygame
+import json
+from math import sin,cos,atan2,pi
+from argparse import ArgumentParser
+
+parser = ArgumentParser()
+parser.add_argument('bot', metavar='bot', type=str, help='ip address of the controlled robot')
+parser.add_argument('id', metavar='id', type=str, help='id of the controlled robot')
+parser.add_argument('meas', metavar='meas', type=str, help='ip address of the measurement server')
+args = parser.parse_args()
+
+bot = args.bot
+meas = args.meas
+
+w = 640
+h = 480
+
+pygame.init()
+surf = pygame.display.set_mode((640, 480))
+bg = pygame.Color(0,0,0)
+botcol = pygame.Color(255, 0, 0)
+setcol = pygame.Color(0, 255, 0)
+
+meas_socket = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
+try:
+    meas_socket.connect((meas, 42424)) # connect to robot
+except socket.error:
+    print("could not connect to measurement socket")
+rc_socket = socket.socket()
+try:
+    rc_socket.connect((bot, 1234)) # connect to robot
+except socket.error:
+    print("could not connect to bot socket")
+
+meas_socket.sendall(f"{args.id}\n".encode())
+
+class Bot(object):
+    FAR, CLOSE, ANGLE, REACHED = range(4)
+    def __init__(self, control):
+        self.sock = control
+        self.state = Bot.REACHED
+        self.tx = self.ty = None
+        self.ta = None
+    
+    def move(self, x, y, angle = None):
+        self.tx = x
+        self.ty = y
+        self.ta = angle
+        self.pps = True
+        self.pas = True
+
+        print()
+        print(f"GOING TO {x},{y}")
+        print()
+
+        self.state = Bot.FAR
+
+    def rotate(self, angle):
+        self.ta = angle
+        self.state = Bot.ANGLE
+
+    def stop(self):
+        self.sock.send(f'(0,0)\n'.encode())
+    def step(self, x, y, angle):
+        umax = 1.0
+
+        if self.tx != None:
+            dp = ((self.tx - x)**2 + (self.ty - y)**2)**0.5
+            da = atan2(self.ty - y, self.tx - x) - angle
+        
+        # Position state: Determine if the angle to the target flips over +-pi/2, i.e. going past the target now
+        def pst(angle):
+            while angle > pi:
+                angle -= 2*pi
+            while angle <-pi:
+                angle += 2*pi
+            return abs(angle) > pi/2
+        # Angle state: When 'close' to target angle (absolute value <= pi/2) use the sign, else 0. When the angle flips over 0, the difference is +- 2
+        def ast(angle):
+            while angle > pi:
+                angle -= 2*pi
+            while angle <-pi:
+                angle += 2*pi
+            return 0 if abs(angle) >= pi/2 else 1 if angle >= 0 else -1
+        # Move with speed and change towards angle
+        def control(speed, angle, backwards = True):
+            ca = cos(angle)
+            speed = speed * cos(angle)
+
+            
+            # Move angle to [0..2*pi]
+            while angle < 0:
+                angle += 2*pi
+            while angle > 2*pi:
+                angle -= 2*pi
+
+            if backwards:
+                # If we can go backwards, angle should be pi or 0
+                if angle >= pi/2 and angle < 3*pi/2:
+                    # pi/2 .. 3/2 pi should move towards pi
+                    angle -= pi
+                    print(f"Go for pi, {angle}")
+                else:
+                    # Everything else should be 0. Make sure angles in 3/2 pi .. 2 pi don't lead to huge outputs.
+                    if angle >= 3*pi/2:
+                        angle -= 2*pi
+                    print(f"Go for 0, {angle}")
+            else:
+                # Have to go forward, just try to get angle to 0
+                # Correct angle to be [-pi..pi]
+                while angle > pi:
+                    angle -= 2*pi
+                    print(f"Always go for 0, {angle}")
+            ul, ur = speed, speed
+            if speed == 0 and abs(angle) < 0.5:
+                angle = 0.5 if angle > 0 else -0.5 if angle < 0 else 0
+            ul -= angle * 0.5
+            ur += angle * 0.5
+            vd = max(1, abs(ul)/umax, abs(ur)/umax)
+            ul /= vd
+            ur /= vd
+            print(f"Movement: {ul},{ur}")
+            self.sock.send(f'({ul},{ur})\n'.encode())
+            self.pps = pst(angle)
+            self.pas = ast(angle)
+
+        if self.state == Bot.FAR:
+            if dp <= 0.3:
+                # Close to the target
+                self.state = Bot.CLOSE
+                self.pps = pst(da)
+            else:
+                # When far, just move towards the target
+                print(f"FAR  {umax}, {da}")
+                control(umax, da)
+        if self.state == Bot.CLOSE:
+            if pst(da) != self.pps and dp <= 0.1:
+                # The angle flips over +- pi/2, go for the angle setpoint
+                self.state = Bot.ANGLE
+                self.pas = 0
+            else:
+                print(f"CLOSE {umax*dp/0.3} {da} {pst(da)} {self.pps}")
+                control(0.3+(umax*dp/0.3), da)
+        if self.state == Bot.ANGLE:
+            if self.ta == None:
+                # No angle setpoint, we're done
+                self.state = Bot.REACHED
+                bot.stop()
+            else:
+                # Use angle setpoint for angle difference
+                da = self.ta - angle
+                # Difference between angle states:
+                # +- 1 means flipping between 'closer than pi/2' and 'further than pi/2'
+                # +- 2 means abs(angle) < pi/2 and the sign changes -> In position!
+                if abs(ast(da) - self.pas) == 2:
+                    # Done
+                    self.state = Bot.REACHED
+                    bot.stop()
+                else:
+                    # Don't move, just rotate
+                    print(f"ANGL {0} {da} {ast(da)} {self.pas}")
+                    control(0, da, False)
+
+meas_file = meas_socket.makefile('rw', encoding='utf8', newline='\n')
+
+bot = Bot(rc_socket)
+bot.move(0, 0, 0)
+
+running = True
+ml = 0.5
+
+scale = 220 / 0.5
+
+while running:
+    received = json.loads(meas_file.readline().strip())
+    received = json.loads(meas_file.readline().strip())
+
+    # Extract position, angle
+    x = received['x']
+    y = received['y']
+    a = received['angle']
+
+    events = pygame.event.get()
+    for event in events:
+        if event.type == pygame.KEYDOWN:
+            if event.key == pygame.K_RIGHT:
+                bot.move(ml, 0, pi)
+            if event.key == pygame.K_LEFT:
+                bot.move(-ml, 0, 0)
+            if event.key == pygame.K_UP:
+                bot.move(0, ml, pi*3/2)
+            if event.key == pygame.K_DOWN:
+                bot.move(0, -ml, pi/2)
+            if event.key == pygame.K_ESCAPE:
+                bot.stop()
+                running = False
+        elif event.type == pygame.MOUSEBUTTONDOWN:
+            x,y = pygame.mouse.get_pos()
+            bot.move((x-w/2)/scale, (y-h/2)/scale)
+
+    surf.fill(bg)
+    pygame.draw.circle(surf, botcol, (w/2 + scale * x, h/2 + scale * y), 10, 2)
+    pygame.draw.line(surf, botcol, (w/2 + scale * x, h/2 + scale * y), (w/2 + scale * x + 15 * cos(a), h/2 + scale * y + 15 * sin(a)))
+    
+    if bot.tx != None and bot.ty != None:
+        pygame.draw.circle(surf, setcol, (w/2 + scale * bot.tx, h/2 + scale * bot.ty), 10, 2)
+        if bot.ta != None:
+            pygame.draw.line(surf, setcol,
+                    (w/2 + scale * bot.tx, h/2 + scale * bot.ty),
+                    (w/2 + scale * bot.tx + 15 * cos(bot.ta), h/2 + scale * bot.ty + 15 * sin(bot.ta)))
+    pygame.display.flip()
+
+    if running:
+        bot.step(x, y, a)
+        
+