Overview
The SensorModule class provides a unified interface to all VEX sensors including distance sensors, inertial sensor, bumper, touchled, and brain screen.
Source: arm_system/vex_brain/src/main.py:63
Class Definition
SensorModule
class SensorModule:
def __init__(self)
Attributes
VEX Brain for screen display
Inertial sensor for heading/rotation measurement
Distance sensor on gripper (PORT7)
RGB LED indicator (PORT8)
Distance sensor on base (PORT9) for scanning
Bumper switch for safety limits (PORT10)
Methods
Screen Methods
clear_screen
Clears the VEX brain screen.
Source: arm_system/vex_brain/src/main.py:72
print_screen
def print_screen(self, text: str, coordinate_x: int, coordinate_y: int)
X coordinate (horizontal position)
Y coordinate (vertical position)
arm_system/vex_brain/src/main.py:75
Inertial Sensor Methods
get_angle
def get_angle(self) -> float
Current heading in degrees (0-360)
arm_system/vex_brain/src/main.py:81
Distance Sensor Methods
get_distance
def get_distance(self, sensor: Distance) -> float
Distance sensor object (base_distance or gripper_distance)
Distance to object in millimeters
arm_system/vex_brain/src/main.py:84
Example
sensor = SensorModule()
# Get base distance
base_dist = sensor.get_distance(sensor.base_distance)
print(f"Base distance: {base_dist}mm")
# Get gripper distance
gripper_dist = sensor.get_distance(sensor.gripper_distance)
print(f"Gripper distance: {gripper_dist}mm")
get_object_size
def get_object_size(self, sensor: Distance) -> int
Raw object size value (sensor-specific units)
arm_system/vex_brain/src/main.py:87
Bumper Methods
is_bumper_pressed
def is_bumper_pressed(self) -> bool
True if bumper is pressed, False otherwise
arm_system/vex_brain/src/main.py:90
LED Indicator Methods
set_color
def set_color(self, color: tuple)
RGB color tuple (red, green, blue) with values 0-255
LED_COLORS = {
'ERROR': (255, 0, 0), # Red
'WARNING': (255, 150, 0), # Orange
'READY': (0, 255, 0), # Green
'RUNNING': (0, 0, 255), # Blue
'INIT': (255, 255, 255) # White
}
arm_system/vex_brain/src/main.py:93
Example
sensor = SensorModule()
# Set to green (ready)
sensor.set_color((0, 255, 0))
# Set to red (error)
sensor.set_color((255, 0, 0))
# Use predefined colors
from main import LED_COLORS
sensor.set_color(LED_COLORS['RUNNING'])
System Check Methods
check_sensors
def check_sensors(self) -> bool
- base_distance (PORT9)
- gripper_distance (PORT7)
- bumper (PORT10)
True if all sensors are installed, False otherwise
arm_system/vex_brain/src/main.py:96
Port Configuration
| Sensor | Port | Purpose |
|---|
| gripper_distance | PORT7 | Detect objects in gripper |
| touchled | PORT8 | Visual status indicator |
| base_distance | PORT9 | Scan environment for objects |
| bumper | PORT10 | Safety limit switch |
| inertial | Default | Base rotation angle |
Usage in RoboticServices
class RoboticServices:
def __init__(self):
self.sensor = SensorModule()
# ... other components
def run_service(self, service):
if service == 'check':
if self.sensor.check_sensors():
self.sensor.set_color(LED_COLORS['READY'])
else:
self.sensor.set_color(LED_COLORS['ERROR'])
Complete Example
from vex import *
LED_COLORS = {
'ERROR': (255, 0, 0),
'WARNING': (255, 150, 0),
'READY': (0, 255, 0),
'RUNNING': (0, 0, 255),
'INIT': (255, 255, 255)
}
class SensorModule:
def __init__(self):
self.brain = Brain()
self.inertial = Inertial()
self.gripper_distance = Distance(Ports.PORT7)
self.touchled = Touchled(Ports.PORT8)
self.base_distance = Distance(Ports.PORT9)
self.bumper = Bumper(Ports.PORT10)
# ... methods ...
# Usage
sensors = SensorModule()
# Check system
if sensors.check_sensors():
sensors.set_color(LED_COLORS['READY'])
sensors.print_screen("System Ready", 10, 10)
else:
sensors.set_color(LED_COLORS['ERROR'])
sensors.print_screen("Sensor Error", 10, 10)
# Monitor distance
while True:
angle = sensors.get_angle()
distance = sensors.get_distance(sensors.base_distance)
sensors.clear_screen()
sensors.print_screen(f"Angle: {angle:.1f}", 10, 20)
sensors.print_screen(f"Distance: {distance}mm", 10, 40)
if sensors.is_bumper_pressed():
sensors.set_color(LED_COLORS['WARNING'])
wait(100, MSEC)
Sensor Specifications
Distance Sensors
- Range: 0-2000mm (varies by model)
- Units: Millimeters (MM)
- Update Rate: ~50Hz
Inertial Sensor
- Range: 0-360 degrees
- Accuracy: ±1 degree
- Requires: Calibration on startup
Bumper Switch
- Type: Digital on/off
- Debounce: Hardware debounced
RGB LED
- Colors: Full RGB (0-255 per channel)
- Modes: Solid color, touch-sensitive