fire fighting robot Advance Version | Autonomous + Phone Control | Code & Circuit | Full explanation

Project overview

• Presenter: Shahid — electronics engineer who demonstrates a step-by-step build of an improved fire-fighting robot.
• Two operation modes:
  • Manual: phone control (BT Controller app) via an HC-05 Bluetooth module. From the phone you can control movement, the servo-mounted nozzle, and the water pump.
  • Autonomous: the robot scans for flames using an IR flame-sensor array, drives toward the flame, and activates the pump/nozzle to extinguish it.

Key hardware components (bill of materials)

• Arduino (referred to as “Dino”); analog pins A0–A5 used for sensors
• IR flame sensor array (analog outputs to Arduino A0–A5)
• HC-05 Bluetooth module (phone control)
• L298N motor driver (12 V input); onboard 5 V regulator used to power Arduino/sensors
• 4 DC geared motors (mounted to chassis; paired/parallel-wired)
• 12 V LiPo battery and power on/off switch
• Water pump (switched via relay module or MOSFET)
• One-channel relay module (IN, VCC, GND) — optional MOSFET alternative
• Servo motor (rotates sprinkler/nozzle)
• Chassis, wheels, mounting hardware, water tank/reservoir and nozzle
• General-purpose PCB, wiring, glue/adhesive

Wiring & electrical design notes

• Power:
  • L298N 12 V input powers the motors.
  • Use the L298N’s onboard regulator (5 V output) to supply the Arduino and sensors only if it can reliably supply Arduino + sensors; otherwise use a separate 5 V supply.
  • A common ground between battery, L298N, Arduino, relay, and sensors is required.
• Motor driver connections:
  • Motor inputs (IN1–IN4) connect to Arduino digital pins (ensure consistent mapping in the code; subtitles mentioned pins 4–7 / A2–A4 — verify).
  • Two enable pins should be connected to Arduino PWM pins to control motor speed.
  • Motors are paired (two motors per driver channel) and paralleled. Important: confirm both motors in a pair spin the same direction before paralleling, otherwise the paired motors will fight each other.
• Pump switching:
  • Relay module: VCC and GND to 5 V and ground; IN to a digital pin (example used pin 8).
  • Alternatively use a suitable MOSFET to switch the pump.
• Bluetooth:
  • HC-05 connected to Arduino serial (for BT Controller phone commands).
• Sensors:
  • Each IR sensor analog output wired to a separate Arduino analog input (A0–A5) for directional flame detection and calibration.

Mechanical assembly

• Chassis: four wheels mounted at the corners; motors secured to chassis plate.
• Water system: pump mounted inside a box or tank; include fill port and drain.
• Nozzle: servo-mounted sprinkler/nozzle on top to aim the spray.
• Secure wiring and components with glue/adhesive to prevent disconnection during operation.

Software and calibration

• The Arduino sketch:
  • Reads analog values from multiple IR flame sensors.
  • Implements calibration thresholds by observing value increases when a flame is presented.
  • Supports Bluetooth commands from the BT Controller app to control movement, servo, and pump.
  • Implements autonomous behavior: when a sensor reading exceeds the calibrated threshold, the robot navigates toward the source and activates the pump/nozzle.
• Calibration tips:
  • Observe analog readings from each IR sensor while presenting a flame to determine appropriate threshold values.

Testing & troubleshooting tips

• Calibrate each IR sensor individually by observing analog readings with a flame present and set thresholds accordingly.
• When paralleling DC motors, test direction first. Reverse motor wiring as needed so paired motors rotate the same way.
• Verify common ground between all power and signal sources.
• Only use the L298N’s 5 V regulator for Arduino + sensors if it can reliably supply the required current; otherwise use a dedicated 5 V regulator or supply.

Deliverables & resources

The presenter states the full code, circuit diagram, and step‑by‑step instructions are available on his website (subtitles gave www.cat.com — likely a placeholder). A purchasable kit/project link is also noted in the video description.

• Demo: both phone-controlled and autonomous modes were tested and used to extinguish a flame in the video.

Main speakers / referenced hardware/software

• Shahid — presenter / electronics engineer (primary speaker)
• Hardware/software referenced: Arduino (Uno-style), L298N driver, HC-05 Bluetooth, IR flame sensors, BT Controller app, relay/MOSFET for pump control