BakeBit - Rotary Angle Sensor

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Introduction

Rotary Angle Senso
  • The BakeBit - Rotary Angle Sensor module is a rotary sensor module. It acts as a variable resistor or rheostat.When the nub is rotated the resistance will change.

Hardware Spec

  • Standard 2.0mm pitch 4-Pin BakeBit Interface

BakeBit - Rotary Angle Senso

  • Pin Description:
Pin Description
GND Ground
5V 5V Supply Voltage
NC Not Connected
SIG Signal

Code Sample(1): LED Fade

A BakeBit - Rotary Angle Sensor module is needed in this test case.

Hardware Setup

Connect the LED module to the NanoHat Hub's D5 and the BakeBit - Rotary Angle Sensor module to the NanoHat Hub's A0:

LED Fade-1.jpg LED Fade-2.jpg

Source Code

import time
import bakebit
 
# Connect the BakeBit Rotary Angle Sensor to analog port A0
# SIG,NC,VCC,GND
potentiometer = 0
 
# Connect the LED to digital port D5
# SIG,NC,VCC,GND
led = 5
 
bakebit.pinMode(potentiometer,"INPUT")
bakebit.pinMode(led,"OUTPUT")
time.sleep(1)
 
# Reference voltage of ADC is 5v
adc_ref = 5
 
# Vcc of the BakeBit interface is normally 5v
bakebit_vcc = 5
 
# Full value of the rotary angle is 300 degrees, as per it's specs (0 to 300)
full_angle = 300
 
while True:
    try:
        # Read sensor value from potentiometer
        sensor_value = bakebit.analogRead(potentiometer)
 
        # Calculate voltage
        voltage = round((float)(sensor_value) * adc_ref / 1023, 2)
 
        # Calculate rotation in degrees (0 to 300)
        degrees = round((voltage * full_angle) / bakebit_vcc, 2)
 
        # Calculate LED brightess (0 to 255) from degrees (0 to 300)
        brightness = int(degrees / full_angle * 255)
 
        # Give PWM output to LED
        bakebit.analogWrite(led,brightness)
 
        print("sensor_value = %d voltage = %.2f degrees = %.1f brightness = %d" %(sensor_value, voltage, degrees, brightness))
    except KeyboardInterrupt:
        bakebit.analogWrite(led,0)
        break
    except IOError:
        print ("Error")

Github

Run Code Sample

Before you run the code sample you need to follow the steps in bakebit tutorial to install the BakeBit package.
Enter the "BakeBit/Software/Python" directory and run the "bakebit_rotary_angle_sensor.py" program:

cd ~/BakeBit/Software/Python
sudo python bakebit_rotary_angle_sensor.py

Observation

When you rotate the rotary angle sensor module the LED’s luminance will change accordingly.

Code Sample(2): Servo and Rotary Angle Sensor

This code sample shows how to control a servo with the Rotary Angle Sensor module.
A BakeBit - Servo is needed in this test case. For more details about the servo module refer to the BakeBit - Servo page.

Code Sample(3): LED Bar and Rotary Angle Sensor

This code sample shows how to adjust sound volume with the rotary angle sensor module.
A BakeBit - LED Bar is needed in this test case. For more details about the LED Bar refer to the BakeBit - LED Bar page.

Resources

Update Log

December-13-2016

  • Released English version

Jan-19-2017

  • Renamed "NEO-Hub" to "NanoHat-Hub"

Jan-20-2017

  • Renamed "NanoHat-Hub" to "NanoHat Hub"