Movement with uncertainty

This commit is contained in:
Danny Staple
2022-12-28 13:26:38 +00:00
parent c87ef96477
commit 6535128a06
14 changed files with 4702 additions and 1 deletions
File diff suppressed because one or more lines are too long
@@ -8,7 +8,7 @@ import adafruit_bno055
uart = busio.UART(board.GP12, board.GP13, baudrate=9600)
wheel_diameter_mm = 70
wheel_diameter_mm = 69.5
wheel_circumference_mm = math.pi * wheel_diameter_mm
gear_ratio = 298
encoder_poles = 28
File diff suppressed because one or more lines are too long
@@ -0,0 +1,50 @@
import numpy as np
from matplotlib import pyplot as plt, patches
from robot import arena
import random
fig, ax = plt.subplots()
# for line in arena.boundary_lines:
# plt.plot([line[0][0], line[1][0]], [line[0][1], line[1][1]], color="black")
poses = np.random.normal([250, 300], [2, 2], size=(200, 2))
ax.scatter(poses[:, 0], poses[:, 1])
# create a line for a motion vector
motion_angle = 30
motion_scale = 300
motion_line = np.array([[250, 300],
[motion_scale * np.cos(np.radians(motion_angle)), motion_scale * np.sin(np.radians(motion_angle))]])
def get_scaled_sample_around_mean(mean, scale):
return mean + (random.uniform(-scale, scale) + random.uniform(-scale, scale)) / 2
rotation_scale = 0.05 * abs(motion_angle) + 0.01 * abs(motion_scale)
translation_scale = 0.05 * abs(motion_scale) + 0.01 * abs(motion_angle)
motion_rotation = np.array([get_scaled_sample_around_mean(motion_angle, rotation_scale) for _ in range(poses.shape[0])])
motion_translation = np.array([get_scaled_sample_around_mean(motion_scale, translation_scale) for _ in range(poses.shape[0])])
new_poses = np.zeros_like(poses)
new_poses[:, 0] = poses[:, 0] + motion_translation * np.cos(np.radians(motion_rotation))
new_poses[:, 1] = poses[:, 1] + motion_translation * np.sin(np.radians(motion_rotation))
# new_poses[:, 0] = poses[:, 0] + motion_scale * np.cos(np.radians(motion_angle))
# new_poses[:, 1] = poses[:, 1] + motion_scale * np.sin(np.radians(motion_angle))
ax.scatter(new_poses[:, 0], new_poses[:, 1])
# plot the vector arrow
ax.arrow(*motion_line[0], *motion_line[1], color="red", width=5)
# plot the angles on top
# line from original cluster middle, going east.
ax.plot([250, 250+100], [300, 300], color="black")
angle = patches.Wedge((250, 300), 100, 0, motion_angle, width=20, color=(0.3, 0.3, 0.3, 0.3))
ax.add_patch(angle)
ax.text(370, 330, f"{motion_angle}°", horizontalalignment="center", verticalalignment="center",
fontsize="x-large")
plt.show()
@@ -0,0 +1,73 @@
import asyncio
import json
import numpy as np
import matplotlib.pyplot as plt
from matplotlib.widgets import Button
from robot_ble_connection import BleConnection
class RobotDisplay:
def __init__(self):
self.ble_connection = BleConnection(self.handle_data)
self.buffer = ""
self.arena = {}
self.closed = False
self.fig, self.ax = plt.subplots()
self.poses = None
def handle_close(self, _):
self.closed = True
def handle_data(self, data):
self.buffer += data.decode("utf-8")
while "\n" in self.buffer:
line, self.buffer = self.buffer.split("\n", 1)
print(f"Received data: {line}")
try:
message = json.loads(line)
except ValueError:
print("Error parsing JSON")
return
if "arena" in message:
self.arena = message
if "poses" in message:
self.poses = np.array(message["poses"], dtype=np.int16)
def draw(self):
self.ax.clear()
if self.arena:
for line in self.arena["arena"]:
self.ax.plot(
[line[0][0], line[1][0]], [line[0][1], line[1][1]], color="black"
)
if self.poses is not None:
self.ax.scatter(self.poses[:,0], self.poses[:,1], color="blue")
async def send_command(self, command):
request = (json.dumps({"command": command}) ).encode()
print(f"Sending request: {request}")
await self.ble_connection.send_uart_data(request)
def start(self, _):
self.button_task = asyncio.create_task(self.send_command("start"))
async def main(self):
plt.ion()
await self.ble_connection.connect()
try:
await self.send_command("arena")
self.fig.canvas.mpl_connect("close_event", self.handle_close)
start_button = Button(plt.axes([0.7, 0.05, 0.1, 0.075]), "Start")
start_button.on_clicked(self.start)
while not self.closed:
self.draw()
plt.draw()
plt.pause(0.05)
await asyncio.sleep(0.01)
finally:
await self.ble_connection.close()
robot_display = RobotDisplay()
asyncio.run(robot_display.main())
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@@ -0,0 +1,22 @@
[tool.poetry]
name = "modelling-space"
version = "0.1.0"
description = ""
authors = ["Danny Staple <danny@orionrobots.co.uk>"]
readme = "README.md"
packages = [{include = "modelling_space"}]
[tool.poetry.dependencies]
python = "^3.9"
matplotlib = "3.6.1"
numpy = "1.23.4"
bleak = "0.19.0"
jupyter = "^1.0.0"
[tool.poetry.group.dev.dependencies]
black = "^22.10.0"
[build-system]
requires = ["poetry-core"]
build-backend = "poetry.core.masonry.api"
@@ -0,0 +1,3 @@
matplotlib==3.6.1
numpy==1.23.4
bleak==0.19.0
@@ -0,0 +1,77 @@
"""Represent the lines of the arena"""
try:
from ulab import numpy as np
except ImportError:
import numpy as np
boundary_lines = [
[(0,0), (0, 1500)],
[(0, 1500), (1500, 1500)],
[(1500, 1500), (1500, 500)],
[(1500, 500), (1000, 500)],
[(1000, 500), (1000, 0)],
[(1000, 0), (0, 0)],
]
width = 1500
height = 1500
grid_cell_size = 50
overscan = 10 # 10 each way
def get_distance_to_segment(x, y, segment):
"""Return the distance from the point to the segment.
Segment -> ((x1, y1), (x2, y2))
All segments are horizontal or vertical.
"""
x1, y1 = segment[0]
x2, y2 = segment[1]
# if the segment is horizontal, the point will be closest to the y value of the segment
if y1 == y2 and x >= min(x1, x2) and x <= max(x1, x2):
return abs(y - y1)
# if the segment is vertical, the point will be closest to the x value of the segment
if x1 == x2 and y >= min(y1, y2) and y <= max(y1, y2):
return abs(x - x1)
# the point will be closest to one of the end points
return np.sqrt(
min(
(x - x1) ** 2 + (y - y1) ** 2,
(x - x2) ** 2 + (y - y2) ** 2
)
)
def get_distance_likelihood(x, y):
"""Return the distance from the point to the nearest segment as a decay function."""
min_distance = None
for segment in boundary_lines:
distance = get_distance_to_segment(x, y, segment)
if min_distance is None or distance < min_distance:
min_distance = distance
return 1.0 / (1 + min_distance/250) ** 2
grid_cell_size = 50
overscan = 10 # 10 each way
# beam endpoint model
def make_distance_grid():
"""Take the boundary lines. With and overscan of 10 cells, and grid cell size of 5cm (50mm),
make a grid of the distance to the nearest boundary line.
"""
grid = np.zeros((
width // grid_cell_size + 2 * overscan,
height // grid_cell_size + 2 * overscan
), dtype=np.float)
for x in range(grid.shape[0]):
column_x = x * grid_cell_size - (overscan * grid_cell_size)
for y in range(grid.shape[1]):
row_y = y * grid_cell_size - (overscan * grid_cell_size)
grid[x, y] = get_distance_likelihood(
column_x, row_y
)
return grid
distance_grid = make_distance_grid()
@@ -0,0 +1,182 @@
import asyncio
import json
import random
from ulab import numpy as np
import arena
import robot
class DistanceSensorTracker:
def __init__(self):
robot.left_distance.distance_mode = 2
robot.right_distance.distance_mode = 2
robot.left_distance.timing_budget = 50
robot.right_distance.timing_budget = 50
self.left = 300
self.right = 300
async def main(self):
robot.left_distance.start_ranging()
robot.right_distance.start_ranging()
while True:
if robot.left_distance.data_ready and robot.left_distance.distance:
self.left = robot.left_distance.distance * 10 # convert to mm
robot.left_distance.clear_interrupt()
if robot.right_distance.data_ready and robot.right_distance.distance:
self.right = robot.right_distance.distance * 10
robot.right_distance.clear_interrupt()
await asyncio.sleep(0.01)
class CollisionAvoid:
def __init__(self, distance_sensors):
self.speed = 0.6
self.distance_sensors = distance_sensors
async def main(self):
while True:
robot.set_right(self.speed)
while self.distance_sensors.left < 300 or \
self.distance_sensors.right < 300:
robot.set_left(-self.speed)
await asyncio.sleep(0.3)
robot.set_left(self.speed)
await asyncio.sleep(0)
def get_scaled_sample_around_mean(mean, scale):
return mean + (random.uniform(-scale, scale) + random.uniform(-scale, scale)) / 2
def send_json(data):
robot.uart.write((json.dumps(data) + "\n").encode())
def read_json():
try:
data = robot.uart.readline()
decoded = data.decode()
return json.loads(decoded)
except (UnicodeError, ValueError):
print("Invalid data")
return None
def send_poses(samples):
send_json({
"poses": np.array(samples[:,:2], dtype=np.int16).tolist(),
})
class Simulation:
def __init__(self):
self.population_size = 20
self.poses = np.array(
[(
int(random.uniform(0, arena.width)),
int(random.uniform(0, arena.height)),
int(random.uniform(0, 360))) for _ in range(self.population_size)],
dtype=np.float,
)
self.distance_sensors = DistanceSensorTracker()
self.collision_avoider = CollisionAvoid(self.distance_sensors)
self.last_encoder_left = robot.left_encoder.read()
self.last_encoder_right = robot.right_encoder.read()
self.alpha_rot = 0.05
self.alpha_rot_trans = 0.01
self.alpha_trans = 0.05
self.alpha_trans_rot = 0.01
def convert_odometry_to_motion(self, left_encoder_delta, right_encoder_delta):
"""
left_encoder is the change in the left encoder
right_encoder is the change in the right encoder
returns rot1, trans, rot2
rot1 is the rotation of the robot in degrees before the translation
trans is the distance the robot has moved in mm
rot2 is the rotation of the robot in degrees
"""
left_mm = left_encoder_delta * robot.ticks_to_mm
right_mm = right_encoder_delta * robot.ticks_to_mm
if left_mm == right_mm:
return 0, left_mm, 0
# calculate the radius of the arc
radius = (robot.wheelbase_mm / 2) * (left_mm + right_mm) / (right_mm - left_mm)
## angle = difference in steps / wheelbase
d_theta = (right_mm - left_mm) / robot.wheelbase_mm
# For a small enough motion, assume that the chord length = arc length
arc_length = d_theta * radius
rot1 = np.degrees(d_theta/2)
rot2 = rot1
return rot1, arc_length, rot2
def apply_motion_to_poses(self, rot1, trans, rot2):
self.poses[:,2] += rot1
rot1_radians = np.radians(self.poses[:,2])
self.poses[:,0] += trans * np.cos(rot1_radians)
self.poses[:,1] += trans * np.sin(rot1_radians)
self.poses[:,2] += rot2
self.poses[:,2] = np.array([float(theta % 360) for theta in self.poses[:,2]])
def apply_randomness_to_motion(self, rot1, trans, rot2):
rot1_scale = self.alpha_rot * abs(rot1) + self.alpha_rot_trans * abs(trans)
trans_scale = self.alpha_trans * abs(trans) + self.alpha_trans_rot * (abs(rot1) + abs(rot2))
rot2_scale = self.alpha_rot * abs(rot2) + self.alpha_rot_trans * abs(trans)
rot1_model = np.array([get_scaled_sample_around_mean(rot1, rot1_scale) for _ in range(self.poses.shape[0])])
trans_model = np.array([get_scaled_sample_around_mean(trans, trans_scale) for _ in range(self.poses.shape[0])])
rot2_model = np.array([get_scaled_sample_around_mean(rot2, rot2_scale) for _ in range(self.poses.shape[0])])
return rot1_model, trans_model, rot2_model
def motion_model(self):
"""Apply the motion model"""
new_encoder_left = robot.left_encoder.read()
new_encoder_right = robot.right_encoder.read()
rot1, trans, rot2 = self.convert_odometry_to_motion(
new_encoder_left - self.last_encoder_left,
new_encoder_right - self.last_encoder_right)
self.last_encoder_left = new_encoder_left
self.last_encoder_right = new_encoder_right
rot1_model, trans_model, rot2_model = self.apply_randomness_to_motion(rot1, trans, rot2)
self.apply_motion_to_poses(rot1_model, trans_model, rot2_model)
print(
json.dumps(
[self.poses.tolist(), rot1, trans, rot2]
)
)
async def main(self):
asyncio.create_task(self.distance_sensors.main())
asyncio.create_task(self.collision_avoider.main())
try:
while True:
send_poses(self.poses)
await asyncio.sleep(0.05)
self.motion_model()
finally:
robot.stop()
async def command_handler(simulation):
print("Starting handler")
simulation_task = None
while True:
if robot.uart.in_waiting:
request = read_json()
if not request:
continue
print("Received: ", request)
if request["command"] == "arena":
send_json({
"arena": arena.boundary_lines,
})
elif request["command"] == "start":
if not simulation_task:
simulation_task = asyncio.create_task(simulation.main())
await asyncio.sleep(0.1)
simulation = Simulation()
asyncio.run(command_handler(simulation))
@@ -0,0 +1,27 @@
class PIDController:
def __init__(self, kp, ki, kd, d_filter_gain=0.1, imax=None, imin=None):
self.kp = kp
self.ki = ki
self.kd = kd
self.d_filter_gain = d_filter_gain
self.imax = imax
self.imin = imin
self.reset()
def reset(self):
self.integral = 0
self.error_prev = 0
self.derivative = 0
def calculate(self, error, dt):
self.integral += error * dt
if self.imax is not None and self.integral > self.imax:
self.integral = self.imax
if self.imin is not None and self.integral < self.imin:
self.integral = self.imin
# Add a low pass filter to the difference
difference = (error - self.error_prev) * self.d_filter_gain
self.error_prev += difference
self.derivative = difference / dt
return self.kp * error + self.ki * self.integral + self.kd * self.derivative
@@ -0,0 +1,84 @@
import rp2pio
import adafruit_pioasm
import array
import asyncio
program = """
; use the osr for count
; input pins c1 c2
set y, 0 ; clear y
mov osr, y ; and clear osr
read:
; x will be the old value
; y the new values
mov x, y ; store old Y in x
in null, 32 ; Clear ISR - using y
in pins, 2 ; read two pins into y
mov y, isr
jmp x!=y, different ; Jump if its different
jmp read ; otherwise loop back to read
different:
; x has old value, y has new.
; extract the upper bit of X.
in x, 31 ; get bit 31 - old p1 (remember which direction it came in)
in null, 31 ; keep only 1 bit
mov x, isr ; put this back in x
jmp !x, c1_old_zero
c1_old_not_zero:
jmp pin, count_up
jmp count_down
c1_old_zero:
jmp pin, count_down
; fall through
count_up:
; for a clockwise move - we'll add 1 by inverting
mov x, ~ osr ; store inverted OSR on x
jmp x--, fake ; use jump to take off 1
fake:
mov x, ~ x ; invert back
jmp send
count_down:
; for a clockwise move, just take one off
mov x, osr ; store osr in x
jmp x--, send ; dec and send
send:
; send x.
mov isr, x ; send it
push noblock ; put ISR into input FIFO
mov osr, x ; put X back in OSR
jmp read ; loop back
"""
assembled = adafruit_pioasm.assemble(program)
class QuadratureEncoder:
def __init__(self, first_pin, second_pin, reversed=False):
"""Encoder with 2 pins. Must use sequential pins on the board"""
self.sm = rp2pio.StateMachine(
assembled,
frequency=0,
first_in_pin=first_pin,
jmp_pin=second_pin,
in_pin_count=2,
)
self.reversed = reversed
self._buffer = array.array("i", [0])
asyncio.create_task(self.poll_loop())
async def poll_loop(self):
while True:
await asyncio.sleep(0)
while self.sm.in_waiting:
self.sm.readinto(self._buffer)
def read(self):
if self.reversed:
return -self._buffer[0]
else:
return self._buffer[0]
+76
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@@ -0,0 +1,76 @@
import board
import pwmio
import pio_encoder
import busio
import adafruit_vl53l1x
import math
import adafruit_bno055
uart = busio.UART(board.GP12, board.GP13, baudrate=9600)
wheel_diameter_mm = 69.5
wheel_circumference_mm = math.pi * wheel_diameter_mm
gear_ratio = 298
encoder_poles = 28
ticks_per_revolution = encoder_poles * gear_ratio
ticks_to_mm = wheel_circumference_mm / ticks_per_revolution
ticks_to_m = ticks_to_mm / 1000
m_to_ticks = 1 / ticks_to_m
wheelbase_mm = 170
distance_sensor_from_middle = 40 # approx mm
motor_A2 = pwmio.PWMOut(board.GP17, frequency=100)
motor_A1 = pwmio.PWMOut(board.GP16, frequency=100)
motor_B2 = pwmio.PWMOut(board.GP18, frequency=100)
motor_B1 = pwmio.PWMOut(board.GP19, frequency=100)
right_motor = motor_A1, motor_A2
left_motor = motor_B1, motor_B2
right_encoder = pio_encoder.QuadratureEncoder(board.GP20, board.GP21)
left_encoder = pio_encoder.QuadratureEncoder(board.GP26, board.GP27, reversed=True)
i2c0 = busio.I2C(sda=board.GP0, scl=board.GP1)
i2c1 = busio.I2C(sda=board.GP2, scl=board.GP3)
left_distance = adafruit_vl53l1x.VL53L1X(i2c0)
right_distance = adafruit_vl53l1x.VL53L1X(i2c1)
imu = adafruit_bno055.BNO055_I2C(i2c0)
def stop():
motor_A1.duty_cycle = 0
motor_A2.duty_cycle = 0
motor_B1.duty_cycle = 0
motor_B2.duty_cycle = 0
def set_speed(motor, speed):
# Swap motor pins if we reverse the speed
if abs(speed) < 0.1:
motor[0].duty_cycle = 0
motor[1].duty_cycle = 1
return
if speed < 0:
direction = motor[1], motor[0]
speed = -speed
else:
direction = motor
speed = min(speed, 1) # limit to 1.0
max_speed = 2 ** 16 - 1
direction[0].duty_cycle = int(max_speed * speed)
direction[1].duty_cycle = 0
def set_left(speed):
set_speed(left_motor, speed)
def set_right(speed):
set_speed(right_motor, speed)
def check_imu_status():
sys_status, gyro, accel, mag = imu.calibration_status
uart.write(f"Sys: {sys_status}, Gyro: {gyro}, Accel: {accel}, Mag: {mag}\n".encode())
return sys_status == 3
@@ -0,0 +1,38 @@
import asyncio
import bleak
class BleConnection:
# See https://learn.adafruit.com/introducing-adafruit-ble-bluetooth-low-energy-friend/uart-service
ble_uuid = "6E400001-B5A3-F393-E0A9-E50E24DCCA9E"
rx_gatt = "6E400003-B5A3-F393-E0A9-E50E24DCCA9E"
tx_gatt = "6E400002-B5A3-F393-E0A9-E50E24DCCA9E"
ble_name = "Adafruit Bluefruit LE"
def __init__(self, receive_handler):
self.ble_client = None
self.receive_handler = receive_handler
def _uart_handler(self, _, data: bytes):
self.receive_handler(data)
async def connect(self):
print("Scanning for devices...")
devices = await bleak.BleakScanner.discover(service_uuids=[self.ble_uuid])
print(f"Found {len(devices)} devices")
print([device.name for device in devices])
ble_device_info = [device for device in devices if device.name==self.ble_name][0]
print(f"Connecting to {ble_device_info.name}...")
self.ble_client = bleak.BleakClient(ble_device_info.address)
await self.ble_client.connect()
print("Connected to {}".format(ble_device_info.name))
self.notify_task = asyncio.create_task(
self.ble_client.start_notify(self.rx_gatt, self._uart_handler)
)
async def close(self):
await self.ble_client.disconnect()
async def send_uart_data(self, data):
await self.ble_client.write_gatt_char(self.tx_gatt, data)