Braitenberg Robot

The Braitenberg Robot is an autonomous mobile robot inspired by Braitenberg Vehicles. It reacts to environmental stimuli, such as light or obstacles, using simple sensor-based behaviors. The robot’s movements are determined by sensor input, enabling it to navigate and interact with its surroundings without predefined paths or waypoints.

About Tools and Materials:

2x SMD Red (Purchase Here)

SMD USB Gateway (Purchase Here)

Arduino Gateway Module (Purchase Here)

2x BDC Motor (Purchase Here)

2x Ambient Light Sensor Module (Purchase Here)

RGB LED Module (Purchase Here)

Button Module (Purchase Here)

Step 1: Hardware & Software Overview

Project Key Components

1. SMD

   The SMD acts as a bridge between the script and the modules. It is responsible for interpreting the commands sent by the script and translating them into actions that read input from the Ultrasonic Distance Sensor Module and meanwhile, actuate the motor for the continuous reading of the script.

2. BDC Motor

   The 100 RPM BDC Motor with Encoder is used to rotate the radar mechanism in a full circle. The user can precisely control the motor and get the position through the built-in encoder.

3. RGB LED Module The RGB LED Module emits light in different colors by mixing red, green, and blue channels. This allows users to create a variety of lighting effects, controlled via the Button Module.

4. Button Module The Button Module serves as a physical interface for user input. Users can press the button to cycle through different colors for the RGB LED Module, and if the button is held down, the system will rapidly cycle through colors, allowing for faster color selection.

5. Ambient Light Sensor Module The Ambient Light Sensor detects the intensity of the surrounding light and allows the system to decide when to automatically turn on or off the RGB LED Module, depending on the environment’s lighting conditions.

Key Features

• Light-Based Behavior Moves based on light intensity using sensors.

• Autonomous Navigation Adjusts speed and direction dynamically.

• Multiple Modes Fear (avoids light), Love (follows light), Aggression, and Wander.

• SMD Red Motor Control Uses PWM for precise movement.

• Button-Controlled Mode Switching Changes behavior with a button press.

• RGB LED Feedback LED color indicates the active mode.

Step 2: Assemble

Connect the SMD Red to the PC or Arduino board using a USB Gateway Module or Arduino Gateway Module.

Connect the BDC Motors with encoders to the motor ports of the SMD.

Attach the Ambient Light Sensor Module, Button Module, and RGB LED Module to the SMD using RJ-45 cables.

Ensure the SMD is powered and all connections are properly secured.

Project Wiring Diagram

Step 3: Run & Test

Power on the SMD Red and ensure all connections are secure.

Run the Python script to initialize the system and scan for connected modules.

Press the button module to switch between different robot behaviors (Fear, Love, Aggression, Wander).

Observe the motor movement and RGB LED color changes based on light sensor inputs.

If the robot does not respond correctly, check the sensor values and motor operation.

Codes

from smd.red import *
import time
import sys

class Braitenberg:
    """ Port and SMD ids are assigned. Modules connected to SMDs are printed.
        The operation mode is set for velocity modes. Torque is enabled
    """
    def __init__(self):
        # SMD setup
        self.port = "/dev/ttyUSB0"
        self.m = Master(self.port)
        self.m.attach(Red(0))
        self.m.attach(Red(1))
        print(self.m.scan_modules(0))  # Print the scanned modules for the first SMD ID.
        print(self.m.scan_modules(1))  # Print the scanned modules for the second SMD ID.
        
        # Motor setup
        # SMD 0 is left motor
        # SMD 1 is right motor
        self.m.set_operation_mode(0, 2)
        self.m.set_operation_mode(1, 2)
        self.m.enable_torque(0, True)
        self.m.enable_torque(1, True)

    def map(self, value, fromLow, fromHigh, toLow, toHigh):
        """_summary_

        Args:
            value (_type_): value of light data from the light sensor
            fromLow (_type_): minimum value of light coming from the light sensor
            fromHigh (_type_): maximum value of light coming from the light sensor
            toLow (_type_): minimum value of velocity
            toHigh (_type_): maximum value of velocity

        Returns:
            _type_: Velocity value is returned in direct proportion to the incoming light value.
        """
        return int((value - fromLow) * (toHigh - toLow) / (fromHigh - fromLow) + toLow)

    def stop(self):
        """The motors are stopped by setting the Velocity value to 0.
        """

        self.m.set_velocity(0, 0)
        self.m.set_velocity(1, 0)

    def get_light_values(self):
        """ Incoming light data is assigned to right and left light variables

        Returns:
            _type_: right and left light values are returned
        """
        left_light = self.m.get_light(0, 1)
        right_light = self.m.get_light(0, 2)
        return left_light, right_light

    def fear(self):
        """ The right motor is related to the light sensor on the right, the left motor is related to the light data 
        from the left sensor in direct proportion. Motor speeds increase in direct proportion to the light data, and 
        accordingly the robot tends to move away from the light.
        """
        left_light, right_light = self.get_light_values()
        
        if left_light is not None and right_light is not None:
            # Adjust PWM values based on light intensity.
            left_stim = self.map(left_light, 0, 2300, 40, 100)
            right_stim = self.map(right_light, 0, 2300, 40, 100)
            print(f"left_light {left_light},  righ_light {right_light} ")

            self.m.set_velocity(0, -left_stim)
            self.m.set_velocity(1, right_stim)
        else:
            self.stop()  # Stop if any sensor is None.
    
    def love(self):
        """
        The right motor is related to the light sensor on the right, the left motor is inversely
        related to the light data from the left sensor. Motor speeds increase inversely proportional to
        the light data, and accordingly the robot tends to approach the light. However, as the robot 
        approaches the light source, its speed decreases.
        """
        
        left_light, right_light = self.get_light_values()

        if left_light is not None and right_light is not None:
            # Adjust PWM values based on light intensity.
            left_stim = self.map(left_light, 0, 1500, 100 ,0)
            right_stim = self.map(right_light, 0, 1500, 100, 0)

            
            if right_stim and left_stim > -1:

                self.m.set_velocity(0, -left_stim)
                self.m.set_velocity(1, right_stim)
            else:
                self.stop()
            print(f"left_stim {left_stim},  right_stim {right_stim} ")

        else:
            self.stop()  # Stop if any sensor is None.

    def wander_around(self):
        
        """The right motor is inversely related to the light sensor on the left,
        the left motor is inversely related to the light data from the right sensor. 
        Motor speeds increase inversely proportional to the light data, and accordingly
        the robot tends to move away from the light. However, as the robot moves away from 
        the light source, its speed increases.
        """
        left_light, right_light = self.get_light_values()

        if left_light is not None and right_light is not None:
            # Adjust PWM values based on light intensity.
            left_stim = self.map(right_light, 0, 1500, 100, 0)
            right_stim = self.map(left_light, 0, 1500, 100, 0)
            self.m.set_velocity(0, right_stim)
            self.m.set_velocity(1, -left_stim)

            print(f"left pwm: {left_stim}, right pwm: {right_stim}")

        else:
            self.stop()  # Stop if any sensor is None.
    
    def agression(self):
        """ The right motor is related to the light sensor on the right, the left motor is related to the light data 
        from the left sensor in direct proportion. Motor speeds increase in direct proportion to the light data, and 
        accordingly the robot tends to move away from the light.
        """

        left_light, right_light = self.get_light_values()

        if left_light is not None and right_light is not None:
            left_stim = self.map(left_light, 0, 1500, 0, 100)
            right_stim = self.map(right_light, 0, 1500, 0, 100)
            self.m.set_velocity(0, -right_stim)
            self.m.set_velocity(1, left_stim)

            print(f"Left: {left_stim}, Right: {right_stim}")

        else:
            self.stop()

    def run(self):
        c = 0
        while True:
            button =self.m.get_button(0, 1)
            
            if button == 1:
                c += 1
                time.sleep(0.4)
                 
            if c == 0:
                print(0) 
                self.fear()
                self.m.set_rgb(0, 1, red = 0, green = 0, blue = 255)
            
            elif c == 1:
                print(1)
                self.love()
                self.m.set_rgb(0, 1, red = 255, green = 0, blue = 255)
            elif c == 2:
                print(2)
                self.agression()
                self.m.set_rgb(0, 1, red = 255, green =0 , blue = 0)
            elif c == 3:
                print(3)
                self.wander_around()
                self.m.set_rgb(0, 1, red = 0, green = 255, blue = 0)
            elif c > 2:
                c = 0


if __name__ == "__main__":

    try:
        
        vehicle = Braitenberg()
        vehicle.run()


    except KeyboardInterrupt:  
        vehicle.stop()
        sys.exit(0)