OUTPUT DEVICES

MISSION BRIEFING

This week's objective: Add an output device to a microcontroller board and program it to do something. I created a Universal Output Shield in the shape of the Red Hood logo to control my final project's mechanics.

STEP 05: FINAL B&W RESULT

This is the Servo that I used for testing. It is a SG90, a common micro servo that can rotate approximately 180 degrees. It has three wires: power (red), ground (brown), and signal (orange). The signal wire receives PWM signals from the microcontroller to control the angle of the servo horn.

00. GROUP ASSIGNMENT

01. THE ACTUATORS

• Servomotor SG90 (For moving targets)
• DC Motor (For high-speed movement)
• TB67H451FNG Driver (The power bridge)
• LiPo Battery 7.4V (Energy source)

02. MY WORKFLOW

I used Inkscape I used the same steps that I used in week06 and week08 to design the PCB in the shape of the Red Hood logo. Then I exported the design to KiCad for layout and routing, and finally sent it to be manufactured.

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01.This is the preview in Kicad.

02. My universal Output Shield is cutted.

03. The finished Universal Output Shield.

03. THE PLOT TWIST: BODGE WIRE

During the mission, I discovered a missing trace between VCC and VREF. Every hero needs a backup plan, so I performed a surgical repair by soldering a Bodge Wire to restore power to the driver.

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01. THE ERROR: The airwire in KiCad showing the missing VREF connection.

02. THE FIX: Soldered jumper wire bridging the power gap.

04. OUTPUT 1: SERVOMOTOR TEST

I used the Monitor serial to control the SG90 servomotor. The code reads angles that I write from the Serial Monitor and moves the servo accordingly. The video below shows the servo responding to commands sent from the computer, demonstrating successful hardware-software integration.

05. THE CODE VAULT

#include <Servo.h>


#include 

Servo miServo;  


const int pinSenal = D9; 

void setup() {

  Serial.begin(9600);
  

  miServo.attach(pinSenal);

  miServo.write(0);

  delay(2000); 
  
  Serial.println("========================================");
  Serial.println("READY TO WORK  ");
  Serial.println("========================================");
  Serial.println("Write a number from 0 to 180");
}

void loop() {
  if (Serial.available() > 0) {
    
    int angulo = Serial.parseInt();
    
    while (Serial.available() > 0) {
      Serial.read();
    }

    if (angulo >= 0 && angulo <= 180) {
      Serial.print("-> MOVING THE SERVO TO: ");
      Serial.print(angulo);
      Serial.println(" .");
      
      // Ejecutamos el movimiento
      miServo.write(angulo);
      
    } else {
      Serial.println("-> ¡Error! THE MECHANISM ONLY ACCEPTS NUMERS FROM 0 TO 180");
    }
  }

}

MISSION ACCOMPLISHED

The targets are moving. Hardware and software fully integrated.