When using a Raspberry Pi 5 instead of Zero, two errors may occur:
-
GPIO error. The Raspberry Pi 5 no longer controls GPIO directly from the CPU; instead, it uses a separate RP1 I/O chip.
-
Real-time error:
Policy control budget exceeded by 0.01
Policy control budget exceeded by 0.013
Policy control budget exceeded by 0.002
Policy control budget exceeded by 0.035
Policy control budget exceeded by 0.007
Below are some solutions we have tested:
- Add an intermediate package, define the same GPIO handling function, and call different handling functions depending on the board.
Raspberry Pi 5 uses:
from gpiozero import LED, Button, AngularServo
from signal import signal, SIGTERM, SIGINT
# Keep track of all devices to clean up on exit
_all_devices = []
#--------------------------
#DigitalOutput
#--------------------------
classDigitalOut:
def __init__(self, pin):
self.dev = LED(pin)
self.dev.off()
_all_devices.append(self.dev)
def on(self):
self.dev.on()
def off(self):
self.dev.off()
#--------------------------
#DigitalInput
#--------------------------
classDigitalIn:
def __init__(self, pin):
self.dev = Button(pin, pull_up=True)
_all_devices.append(self.dev)
@property
def is_active(self):
return self.dev.is_pressed
#--------------------------
# Servo / PWM Output for Antennas
#--------------------------
classPWMOut:
def __init__(self, pin, frequency=50, min_pulse=0.0005, max_pulse=0.0025):
# frequency ignored for compatibility
self.dev = AngularServo(
pin,
min_angle=0,
max_angle=180,
min_pulse_width=min_pulse,
max_pulse_width=max_pulse
)
self.current_angle = 90 # start at middle
self.dev.angle = self.current_angle
_all_devices.append(self.dev)
def set_duty(self, duty_percent):
duty_percent = max(0, min(duty_percent, 100))
angle = duty_percent * 180 / 100
self.dev.angle = angle
self.current_angle = angle
def stop(self):
self.dev.detach()
#--------------------------
#Cleanup
#--------------------------
def cleanup():
for dev in _all_devices:
if hasattr(dev, "off"):
dev.off()
if hasattr(dev, "close"):
dev.close()
if hasattr(dev, "detach"):
dev.detach()
_all_devices.clear()
# automatically cleanup on SIGINT or SIGTERM
def _signal_handler(signum, frame):
cleanup()
exit(0)
signal(SIGINT, _signal_handler)
signal(SIGTERM, _signal_handler)
For use outside Raspberry Pi 5:
import RPi.GPIO as GPIO
GPIO.setwarnings(False)
GPIO.setmode(GPIO.BCM)
classDigitalOut:
def __init__(self, pin):
self.pin = pin
GPIO.setup(pin, GPIO.OUT)
GPIO.output(pin, GPIO.LOW)
def on(self):
GPIO.output(self.pin, GPIO.HIGH)
def off(self):
GPIO.output(self.pin, GPIO.LOW)
classDigitalIn:
def __init__(self, pin):
self.pin = pin
GPIO.setup(pin, GPIO.IN, pull_up_down=GPIO.PUD_UP)
@property
def is_active(self):
return GPIO.input(self.pin) == GPIO.LOW
- Real-time processing
Modify v2_rl_walk_mujoco.py
def run(self):
i = 0
last_t = time.perf_counter() # <<< CHANGED >>>
try:
print("Starting")
while True:
now = time.perf_counter() # <<< CHANGED >>>
dt = now - last_t # <<< CHANGED >>>
last_t = now # <<< CHANGED >>>
dt = min(dt, 1.5 / self.control_freq) # <<< CHANGED >>>
if self.commands:
self.last_commands, self.buttons, lt, rt = (
self.ps4_controller.get_last_command()
)
if self.buttons.LB.is_pressed:
self.phase_frequency_factor = 1.3
else:
self.phase_frequency_factor = 1.0
if self.buttons.X.triggered and self.duck_config.projector:
self.projector.switch()
if self.buttons.B.triggered and self.duck_config.speaker:
self.sounds.play_random_sound()
if self.duck_config.antennas:
self.antennas.set_position_left(lt)
self.antennas.set_position_right(rt)
if self.buttons.A.triggered:
self.paused = not self.paused
print("PAUSE" if self.paused else "UNPAUSE")
if self.paused:
time.sleep(0.05)
continue
obs = self.get_obs()
if obs is None:
continue
phase_speed = (
self.phase_frequency_factor + self.phase_frequency_factor_offset
)
self.imitation_i += dt * self.control_freq * phase_speed # <<< CHANGED >>>
self.imitation_i %= self.PRM.nb_steps_in_period # <<< CHANGED >>>
phase = self.imitation_i / self.PRM.nb_steps_in_period * 2 * np.pi
self.imitation_phase = np.array([np.cos(phase), np.sin(phase)])
action = self.policy.infer(obs)
self.last_last_last_action = self.last_last_action.copy()
self.last_last_action = self.last_action.copy()
self.last_action = action.copy()
self.motor_targets = self.init_pos + action * self.action_scale
if self.action_filter is not None:
self.action_filter.push(self.motor_targets) self.motor_targets = self.action_filter.get_filtered_action()
head_motor_targets = self.last_commands[3:] + self.motor_targets[5:9]
self.motor_targets[5:9] = head_motor_targets
action_dict = make_action_dict(
self.motor_targets, list(self.hwi.joints.keys())
)
self.hwi.set_position_all(action_dict)
#print("Real loop Hz:", round(1 / dt, 1)) # <<< CHANGED >>>
except KeyboardInterrupt:
if self.duck_config.antennas:
self.antennas.stop()
print("TURNING OFF")
After the above changes, the mechanical duck's behavior is basically the same as the previous version. However, there may be better ways to handle this. Hopefully, other users have also made changes, and I would appreciate any feedback.
When using a Raspberry Pi 5 instead of Zero, two errors may occur:
GPIO error. The Raspberry Pi 5 no longer controls GPIO directly from the CPU; instead, it uses a separate RP1 I/O chip.
Real-time error:
Below are some solutions we have tested:
Raspberry Pi 5 uses:
For use outside Raspberry Pi 5:
Modify v2_rl_walk_mujoco.py
After the above changes, the mechanical duck's behavior is basically the same as the previous version. However, there may be better ways to handle this. Hopefully, other users have also made changes, and I would appreciate any feedback.