Objectives:
• Study Bernoulli’s Principle, Newton’s Third Law in aviation, and aerodynamic
forces.
• Understand lift, drag, thrust, weight, and stability.
• Learn about primary and secondary control surfaces.
Outcomes and Learnings:
Bernoulli's Principle: It is a key concept in fluid dynamics, which states that as the speed of a fluid increases, the pressure within the fluid decreases.
This principle is based on the conservation of energy, meaning the total energy of a fluid remains constant as it flows, and it applies to both liquids and gases. Essentially, a faster-moving fluid exerts less pressure, and a slower-moving fluid exerts more pressure.
Newton's Third Law in Aviation: When an airfoil, like a wing or a propeller, moves through the air, it forces the air downward (action). According to Newton's third law, there's an equal and opposite reaction that results in a lift, pushing the airfoil and the attached aircraft upward.
In the case of Helicopters, when the main rotor of the helicopter rotates, it creates a torque in opposite direction on the body of the helicopter.
This is counteracted by the tail rotor, which is placed on the end of the helicopter.
There are other ways to counteract this torque, which is as follows:
This use of tandem rotors also offers extra maneuverability to the helicopter.
The Osprey has two large proprotors, one on each wingtip.
These rotate in opposite directions:
V-22 Osprey can be used as a plane as well as a helicopter.
Aerodynamic Forces: The primary aerodynamic forces acting on an aircraft are lift, weight, thrust, and drag. These forces are fundamental to flight, balancing each other to enable an aircraft to stay aloft and move through the air.
Stability: In aircraft, stability refers to the tendency to return to a balanced state after being disturbed.
Factors Affecting Stability:
Aircraft Design: Wing shape, tail size, and wing placement all affect stability.
Weight Distribution: The center of gravity plays a crucial role in stability.
Airflow: The way air flows over the aircraft also influences stability.
Aircraft Control Surfaces:
Primary control surfaces are essential for basic flight maneuvers, including ailerons (for roll), elevators (for pitch), and rudder (for yaw).
Secondary control surfaces enhance performance and flight characteristics, including flaps, slats, spoilers, and trim tabs.
Turbulence is the irregular or unsteady movement of air that causes an aircraft to bump, shake, or jolt during flight. It’s common and usually not dangerous, but it can feel unsettling.
It's caused by Jet stream (fast moving narrow air currents), storms, clouds which contain unstable air.
How Planes Handle Turbulence
Propeller in a Turbulence
Fewer blades on a propeller tend to be more efficient in terms of turbulence and overall performance.
A two-bladed propeller is often more efficient than a three-bladed one, and a three-bladed propeller is more efficient than a four-bladed one, especially in terms of minimizing turbulence.
Objective:
Design an airfoil with NACA 4412 coordinates in Fusion 360. Use the DAT to spline converter or canvas tool to sketch the airfoil. Understand terms such as angle of attack, camber line, chord line, and leading edge. Design two versions: one using a wood environment and another using composites. The wing should generate at least 5 newtons of lift at a wind speed of 25 m/s.
Learnings: I learnt about NACA 4412 coordinates and basic terms related to planes.
NACA stands for National Advisory Committee for Aeronautics.
The four-digit NACA series follows a specific format: NACA MPXX
M = 4 → Maximum camber is 4% of the chord length.
P = 4 → Maximum camber location is at 40% (0.4c) of the chord from the leading edge.
XX = 12 → Maximum thickness is 12% of the chord length.
Basic Terms in Flying:
1.Angle of Attack (AOA): The AOA is the angle at which the chord of an aircraft's wing meets the relative wind. The chord is a straight line from the leading edge to the trailing edge.
2.Leading Edge: The part of the aircraft that meets the airflow (or fluid flow) first.
3.Trailing Edge: The part of an object where the airflow leaves.
4.Chord Line: It is an imaginary straight line that runs from the leading edge (front of the wing) to the trailing edge (back of the wing).
5.Camber Line: The camber line is an imaginary curved line that runs midway between the upper and lower surfaces of an airfoil.
Objectives: To understand and identify essential UAV components and their compatibility.
Task:
Identify and understand flight controllers (Pixhawk, APM), ESCs, motors, propellers, and battery management.
Learn about LiPo, Li-ion, and NiMH batteries, their charge cycles, and safety.
List all the components required to build a quadcopter with a minimum thrust-to-weight ratio of 3:1, each of the components should be compatible with each other.
Perform manual pen-and-paper calculations for flight time and thrust-to-weight ratio using component datasheets
Use E-Calc to verify the results.
Outcomes and Learnings:
Flight Controller
A Flight Controller (FC) is the central brain of a drone.
It is an electronic circuit board that processes input from sensors, receivers, GPS, and user commands — and then sends appropriate signals to the motors (via ESCs) to control the drone's flight.
The size of the drone sensors are very small.
For scaling these components, MEMS is used. MEMS stands for Micro-Electro-Mechanical Systems — a technology that integrates tiny mechanical structures (like sensors, actuators, or motors) with electronics on a micro-scale, typically on a silicon chip.
For more accurate and reliable data, Sensor Fusion technology is used. Sensor Fusion is a technology that combines data from multiple sensors to produce more accurate, reliable, and comprehensive information than what could be achieved using a single sensor alone.
Pixhawk is such open-source flight controller hardware platform widely used in drones, UAVs, and robotics. It supports advanced flight capabilities like autonomous missions, GPS-based navigation, and sensor fusion, and is typically used with ArduPilot or PX4 firmware.
Nomenclauture of Motor
Nomenclature of Propeller
Propeller rating is as : x*y which refers to as Diameter * Pitch in inches.
xyR means the propeller would rotate in reverse i.e. in Clockwise direction.
Some basic informations about propellers:
PWM (Pulse Width Modulation)
Used For: Motor control via ESCs, RC input
How It Works: Varies signal width (in microseconds) to represent throttle/servo values.
Limitations: Susceptible to electrical noise; limited number of channels.
MAVLink (Micro Air Vehicle Link)
Used For: Communication between the flight controller and ground station (Mission Planner, QGroundControl), telemetry modules, companion computers (e.g., Raspberry Pi).
Type: Lightweight, bi-directional communication protocol
Ports: Typically over UART (serial), USB, or telemetry radios
Purpose: Telemetry, commands, sensor data, mission planning.
MAVLink is the universal language that connects your drone’s flight controller with the outside world — including the ground control station, telemetry radio, and even onboard computers.
Formulae required for the calculations:
Thrust to Weight Ratio Calculations:
Flight time Calculations:
Result on the E-Calc Website:
Objective: To understand propeller fundamentals and simulate its aerodynamic performance.
Outcomes and Learnings:
Every airplane propeller has the rating as: x*y, which refers to as Diameter * Pitch in inches.
Example: 10*4.5 means 10 inches is the Diameter and 4.5 inches is the Pitch.
Diameter is tip-to-tip size of the propeller.
Pitch is how far the propeller would travel forward in one revolution (in still air).
How the size of diameter and propeller affects the functions and applications of the propeller:
Terminology
Small Diameter: Shorter span from tip to tip → spins faster, less drag, lower thrust.
High Pitch: Steeper blade angle → more air moved per rotation, higher speed.
Terminology
Large Diameter: Bigger blade span → moves more air, generates more thrust, good for lift.
Low Pitch: Shallower blade angle → less forward movement per rotation, better for control.
Need: If all Propellers spin the same way, then the drone will spin uncontrollably in the opposite direction due to torque.
It cannot yaw or stabilize properly.
The flight controller cannot compensate for the unbalanced forces.
Main Reason: When a propeller spins, it creates torque (rotational force).
According to Newton’s Third Law, if all props spun the same direction, the drone’s body would spin in the opposite direction of the props — uncontrollably.
To cancel this, drones use equal numbers of CW and CCW props.
This opposite rotation pattern balances the torque and allows the drone to:
The other way to identify the clockwise and counterclockwise rotation is to check by rotating the propeller such that the leading edge faces the air first.
If the leading edge faces air first when rotating clockwise, then it's a clockwise rotating propeller. The naming of such a propeller would be like 6030R.
On the other hand, if the leading edge faces air first when its rotated counter clockwise, then it's a counter clockwise propeller. The naming of such a propeller would be like 6030.
Note: CCW is the normal rotation.
Example: 6030R means the propeller would rotate in reverse, i.e. Clockwise direction.
Factor | Explanation |
---|---|
1. Propeller Diameter | Larger diameter props can move more air and generate more thrust at lower RPMs, improving efficiency—but they require more space. |
2. Pitch | Higher pitch moves more air per rotation (good for speed), but may overload the motor. Lower pitch is better for low-speed control. Efficiency depends on matching pitch to the flight requirement. |
3. Number of Blades | More blades = more thrust, but also more drag. Fewer blades = higher efficiency (less drag), but reduced thrust. |
4. Blade Shape and Airfoil | Efficient blade designs reduce drag and improve lift. Thin, smooth, and well-tapered blades are generally more efficient. |
5. RPM (Rotations Per Minute) | Efficiency is better at lower RPMs with larger props. High RPM increases drag and losses. Optimal RPM varies with design. |
6. Motor Matching | An efficient prop must be matched with the right motor KV rating and power curve. A mismatch leads to poor efficiency and overheating. |
7. Material and Weight | Lighter materials (like carbon fiber) reduce inertial load and increase responsiveness and efficiency. Heavier props may reduce efficiency. |
8. Air Density | Higher altitude or hot weather = lower air density → reduced thrust and efficiency. |
9. Load (Thrust Requirement) | A propeller running near its optimal load is more efficient. Overloading or underloading reduces efficiency. |
10. Cleanliness and Damage | Dirt, nicks, or warping on the blades can cause turbulence and reduce efficiency. |
11. Installation Direction | Incorrect orientation (e.g., CW vs CCW mismatch) results in poor performance or failure to generate thrust. |
12. Vibration and Balance | Imbalanced props create vibrations, reduce efficiency, and stress the motor and airframe. |
The first step is to Open New Design and start the model making as guided in the referenced video.
Make the three profile planes and use Loft option to complete 3D sketch.
Duplicate the one side propeller on the opposite side of the cylinder.
Finish the sketch by doing some minor changes and the propller design is ready.
Features Used in Fusion 360:
Sketch Tool: For creating 2D profiles.
Loft Tool: For transforming 2D sketches into 3D geometries.
Circular Pattern Tool: For making the cylindrical part at one end of the propeller, after which the other side of the propeller is duplicated.
Fit Point Spline is a type of spline curve that passes through specific points (called fit points) you define in a sketch.
Objective: To control the speed of a BLDC motor using Arduino UNO, ESC, and a potentiometer.
Outcomes and Learnings: A BLDC motor stands for Brushless Direct Current Motor. It’s a type of electric motor widely used in drones, RC vehicles, robotics, and other electronics due to its efficiency, reliability, and performance.
Arming of ESC:
When initially powering the motor, the signal value must be the same or lower than the minimum value of 1 millisecond. This is called arming of the ESC, and the motor makes a confirmation beeps so that we know that it’s properly armed.
In case we have higher value when powering, which means we have a throttle up, the ESC won’t start the motor until we throttle down to the correct minimum value. This is very convenient in terms of safety, because the motor won’t start in case we have a throttle up when powering.
Every ESC has its own high and low points, and they might slightly vary. For example, the low point might be 1.2 milliseconds and the high point might be 1.9 milliseconds. In such a case, our throttle won’t do anything in the first 20% until it reaches that low point value of 1.2 milliseconds. To solve this issue, we can calibrate the ESC or set the high and low points as we want.
Throttle Control: Converts input signals (from receiver or flight controller) into motor speed by adjusting voltage and current.
Brushless Motor Commutation: For brushless motors, it electronically switches the current through motor windings to create rotation.
An ESC needs calibration when it does not correctly interpret the full throttle range from your transmitter or flight controller.
ESC Calibration:
Objective: Learn about radio frequencies used in UAVs (2.4GHz, 5.8GHz, LoRa).
Understand the various security implications in the different wireless protocols used in drones, along with the emerging threats and ways of mitigation.
Understand the procedure which goes behind the binding of an ELRS receiver.
Bind the 2.4 GHz RP1 Rx with the TX 16S MK-ll.
Outcomes and Learnings:
Feature | 2.4 GHz | 5 GHz |
---|---|---|
Frequency Range | ~2.4 to 2.5 GHz | ~5.15 to 5.825 GHz (varies by region) |
Speed | Lower maximum speed (up to ~600 Mbps) | Higher maximum speed (up to several Gbps) |
Range | Longer range (better wall penetration) | Shorter range (weaker penetration) |
Channels Available | 11 (3 non-overlapping) | 25 non-overlapping |
Interference | Higher (used by many devices: Bluetooth, etc) | Lower (less congested, more channels) |
Best For | Larger coverage areas with fewer devices | High-speed, short-distance connections |
Latency | Typically higher | Lower latency (better for gaming, streaming) |
Device Compatibility | Supported by almost all Wi-Fi devices | Newer devices required for full support |
LoRaWAN: Long Range Wide Area Network
It uses unlicensed frequency band for long-range communication. It is built on top of LoRa (Long Range), which is a physical layer modulation technique.
It is classified into 3 classes: Class A, Class B, Class C.
Class A | Class B | Class C |
---|---|---|
Longest battery life | Average battery life | Longest battery life |
Stays in sleep mode for majority of the time | Listens to network perodically | Listens to network continuously |
Example-Fire Alarm | Example- Metering of temperature, humidity | Example- Traffic monitoring |
LoRa Architecture:
The frequency band used by LoRa varies region by region. In India, it operates in the 865–867 MHz band.
Drone Components:
Component | Function | Key Protocols Used | Potential Vulnerabilities |
---|---|---|---|
Command & Control (C2) | Transmits pilot instructions to the drone | 2.4 GHz/5.8 GHz Wi-Fi, FHSS, DSSS, LTE, SATCOM | Signal interception, jamming, protocol spoofing |
Telemetry Data | Provides real-time flight data (position, altitude, speed) | MAVLink, DJI Lightbridge, LoRa, DroneCAN | Data injection, signal hijacking |
Video Transmission | Sends live feed to the pilot or external system | FPV (Analog or Digital), OcuSync, Wi-Fi, 5G LTE | Man-in-the-middle (MITM) attacks, feed interception |
Navigation & GPS | Enables autonomous navigation and geofencing | GPS, GLONASS, BeiDou, Galileo | GNSS spoofing, jamming, denial of service |
Payload Data Link | Transfers sensor and payload data | 4G/5G, SATCOM, proprietary links | Data exfiltration, interference, encryption bypass |
i) 2.4 GHz & 5.8 GHz Radio Control (RC) Signals
ii) Wi-Fi-Based Drone Control
iii) MAVLink Protocol: Open-Source Telemetry Standard
iv) 4G/5G LTE & SATCOM-Controlled Drones
1.GNSS Spoofing & GPS Jamming
Attackers can transmit counterfeit GPS signals, tricking drones into miscalculating their location.
Impact: UAVs can be forced to change flight paths or even crash.
Countermeasure: Multi-constellation GNSS receivers and inertial navigation backups.
2.Signal Hijacking & Remote Takeover Attacks
Weak encryption allows attackers to inject false commands into drone control links.
Countermeasure: Strong encryption (e.g., AES-256) and authentication-based command inputs.
3.Network-Based Attacks on Wi-Fi-Controlled Drones
Wi-Fi-controlled drones are highly susceptible to deauthentication and MITM attacks.
Countermeasure: WPA3 encryption, SSID broadcasting disablement, and dynamic IP allocation.
1.RF Spectrum Monitoring
Passive RF monitoring detects UAV emissions within the 300 MHz – 6 GHz range.
Helps identify C2 links, telemetry beacons, and FPV signals in real time.
2.Encrypted Telemetry & Secure Authentication
Implementing secure command authentication prevents unauthorized access.
End-to-end encryption minimizes hijacking risks.
3.Deep Packet Inspection for Networked UAVs
Cellular-connected drones can be identified via traffic analysis.
Detects suspicious drone activity over LTE networks.
4.Adaptive Counter-UAS Technologies
AI-driven RF anomaly detection classifies drone activity.
Multi-sensor fusion (RF, radar, EO/IR cameras) enhances detection accuracy.
Some other Drone Protocols are:
Protocol | Full Form | Key Features |
---|---|---|
CRSF | Crossfire (by TBS) | Low latency, long range (900 MHz), supports telemetry |
SBUS | Serial Bus (by FrSky) | Digital protocol, supports 16 channels, older but widely used |
IBUS | FlySky iBUS | Digital, less noisy than PWM, used in FlySky systems |
PWM | Pulse Width Modulation | Analog, one wire per channel, simple but outdated |
PPM | Pulse Position Modulation | Combines multiple PWM signals into one wire |
FPort | FrSky FPort | Combines SBUS + telemetry on a single wire |
Ghost | ImmersionRC Ghost | Low latency, used for racing drones (2.4 GHz) |
Tracer | TBS Tracer | High-speed 2.4 GHz protocol optimized for racers |
DSM2/DSMX | Spektrum protocols | Used in Spektrum RC systems, DSMX offers better interference resistance |
Objective: Understand PID tuning for UAV stability
Learn how GPS Hold and Altitude Hold work, tabulate the differences between the two
Tabulate the differences between GPS Hold and Altitude Hold
Outcomes and Learnings: In drones, a PID (Proportional-Integral-Derivative) control system is a sophisticated method for maintaining stable flight and precise control over various aspects like altitude, orientation, and movement. It works by continuously calculating the difference between the drone's desired state and its current state, then adjusting motor speeds to minimize that difference.
P – Proportional
I – Integral
D – Derivative
An example to better understand it:
Imagine driving a car to stay in the center of a lane:
The final PID output is added to the current control input to adjust the system toward the setpoint.
Altitude Hold is used when flying in calm indoor/outdoor areas and want help with vertical stability.
GPS Hold is used when you want the drone to hover in one place without drifting, especially outdoors.
GPS-Global Positioning System
The following tabular column provides more insight on the difference between the two.
Feature | Altitude Hold | GPS Hold (Position Hold) |
---|---|---|
Function | Maintains constant altitude | Maintains altitude and horizontal position |
Sensors Used | Barometer / IMU | GPS + Barometer / IMU |
Horizontal Stability | Not maintained (can drift) | Maintained (resists wind and movement) |
Wind Resistance | No compensation | Automatically corrects for wind |
Use Case | Indoor or GPS-denied environments | Outdoor flying with GPS signal |
Precision | Moderate (altitude only) | High (position and altitude) |
Navigation Ability | No position lock | Locks current GPS coordinates |
Drift Control | Manual correction required | Automatically stabilized |
Objectives: Explore, learn & understand the use case of the following flight modes in the Mission Planner software:
Stabilize, ACRO,Altitude Hold, Auto, Guided, Loiter, Return to Home (RTL),Circle,
Land, Drift, Pos Hold, Guided_NoGPS, Smart RTL, Follow Mode,
Outcomes and Learnings:
Drone Registration Process in India is as follows:
Nano Drones: Up to 250 grams.
Micro Drones: 250 grams to 2 kilograms.
Small Drones: 2 to 25 kilograms.
Medium Drones: 25 to 150 kilograms.
Large Drones: Above 150 kilograms.
In India, drone airspace is divided into three zones:
Green Zone: Airspace up to 400 feet (120m) in uncontrolled airspace. No permissions needed.
Yellow Zone: Controlled airspace, usually 5-12 km around an airport. Permission required.
Red Zone: Prohibited airspace. No-fly areas
Drone Airspace Map for Bengaluru
The flow chart for the AIrspace zones is as follows:
Drone Height Restrictions:
References:
BVLOS stands for Beyond Visual Line of Sight. It refers to drone operations where the drone is flown beyond the pilot's ability to see it with the naked eye, relying on telemetry and other technologies for remote control and monitoring.
BVLOS operations often require specific permits and approvals from aviation authorities, such as the Ministry of Civil Aviation in India.
Common BVLOS use cases include inspecting remote or large-scale infrastructure, such as oil pipelines, wind farms, and power transmission lines.
BVLOS is also used in emergency response scenarios, like Drone as First Responder (DFR) programs, where drones are deployed to survey incidents before ground units arrive.
India's DGCA (Directorate General of Civil Aviation) has regulated BVLOS operations under the Drone Rules, 2021 and subsequent BVLOS Experimental Guidelines.
Pre-defined Airspace Corridors only
Impact: You can only plan BVLOS flights within DGCA-approved flight corridors or sandbox areas.
Result: No arbitrary path selection; you must operate within a mapped, pre-authorized zone.
Mandatory Regulatory Permissions
Must obtain: BVLOS flight approval from DGCA.
Airspace clearance through the DigitalSky platform.
Impact: Flight planning includes scheduling permissions at least 24–72 hours in advance, affecting mission timelines.
Impact: Flight path needs geofencing, obstacle data, and precise altitude mapping
Impact: Must plan for data logging, storage, and report generation.
Aspect | Effect of BVLOS on Safety |
---|---|
Human Awareness | Reduced (no visual monitoring) |
Automation & Redundancy | Improved safety tech required |
Risk of Collision | Without good DAA systems |
Flight Recovery | Harder in case of emergency |
Compliance Required | Strict SOPs and equipment mandates |
Overall Safety | Can be safe if well-regulated and technically supported |