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Drone Satellite Launch Vehicle – 2023 Payload Satellite / Space Camera / Geiger Station Payload Tube Passenger / Cargo Passenger  Launches of Payload from Artificial Satellites College / Institute...

Drone Satellite Launch Vehicle – 2023 Payload Satellite / Space Camera / Geiger Station Payload Tube Passenger / Cargo Passenger  Launches of Payload from Artificial Satellites College / Institute / University Payload ANUSAT -- Anna University ,Chennai Amateur radio and technology demonstration Studsat -- a consortium consists of NMIT, Bangalore Remote sensing camera MSRIT, Bangalore BMSIT, Bangalore PRATHAM -- IIT – Bombay TEC in the Earth's ionosphere. SRMSAT -- SRM University, Chennai Remote sensing camera Jugnu -- IIT - Kanpur Remote sensing camera NIUSAT - Noorul Islam University, Remote sensing camera Nagerkoil PISAT - PES Inst. Of Technology Remote sensing camera Pune University Point-to-point messaging for HAM community Satyabamasat – Satyabama University, Infrared Spectrometer to study Greenhouse Chennai gases  Satellite Design Driver ❖ Payload must be firmly held on to platform ❖ Structure ❖ Payload must be pointed to required direction ❖ ADCS ❖ Data from payload must reach ground station ❖ RF system ❖ Powering of Payload ❖ Power system ❖ Temperature maintenance, cooling/heating req. ❖ Thermal control ❖ Payload to be operated & its Health monitored ❖ Telecommand & Telemetry  Earth Imaging Payloads ❖ Application: study or monitoring of natural resources on Earth ❖ An Electro-optical camera to image selective areas on Earth and transmit the image data to ground station ❖ Resolution and area coverage will depend on camera design and the orbit into which satellite is launched ❖ Applications include – study of coastal zones, deforestation, water bodies, agricultural patterns etc,. Drone Satellite Launch Vehicle – 2023 Electrical Power Systems  EPS Overview Battery ❖ Battery: Voltage source of the system. Switch ❖ Switch: Electrical component used for the voltage on/off control. ❖ Voltage Divider: Provides measurement of voltage level Voltage Divider ❖ Microcontroller: Atmega microcontroller unit for data handling. ❖ Voltage Regulator: To regulate voltage in order to supply system. Microcontrolle r ❖ Sensors: Ensure data measurement like temperature, pressure and etc. Sensors Voltage Regulator  Electrical Power System ❖ The primary role of the Electrical Power System (EPS) is to supply other systems in the satellite with the necessary electrical power to operate effectively. EPS Power Energy Power Power Regulation Source Storage Distribution and Control  Energy Storage ❖ Rechargeable batteries are used to power equipment and payload, during and after launch (incase of no solar panels or during solar eclipse periods). ❖ This ensures steady communication and functioning  Solar Cells Materials & Efficiency Si (substrate) - 17% GaAs - 20% GaAs/Ge – 19% InP (epitaxial) - 17% Dual Junction (GaAs based) – 22% Triple (Multi) Junction – 30%  Solar Array ❖ Solar Array is a combination of Solar Cells arranged in series and parallel configuration. ❖ Cells in series provide the required voltage ❖ Cells in parallel provide required current ❖ Design considerations – Radiation effects, diode drops, Loss factors etc. Construction of Solar Panel  Solar Array Sizing ❖ Based on Load Power and battery charging requirements ❖ Deteriorating generation over time, seasonal variation and end of life generation are major influencers ❖ Packing efficiency ❖ Type of Cell - Monocrystalline, Polycrystalline, and Thin-film Series-Parallel (s-p) topology Parallel Series (p-s) topology (TCT)  Satellite Power System Generate a DC voltage (Un-interrupted) to meet the electrical power requirements of various functional elements of the satellite Power Source + SUB (Solar) Controller SYSTEMS Board LOAD ON Energy - SATELLITE Storage (Battery) Deployment of Solar Array  Energy Storage By Batteries ❖ Battery consists of electrochemical cells that can convert chemical energy into electrical energy (redox reaction). ❖ Battery consists of : Anode Cathode Electrolyte Separator Collector  Parts of Battery ❖ Container: Steel can that houses and be a part of the electrochemical reaction. ❖ Cathode: A combo of manganese dioxide and carbon, cathodes are the electrodes reduced by the electrochemical reaction. ❖ Separator: Non-woven, fibrous fabric that separates the electrodes. ❖ Anode: Made of powdered zinc metal, anodes are electrodes that are oxidized. ❖ Electrolyte: Potassium hydroxide solution in water, the electrolyte is the medium for the movement of ions within the cell. It carries the iconic current inside the battery. ❖ Collector: Brass pin in the middle of the cell that conducts electricity to the outside circuit.  Major Types Of Batteries Types of Battery Types of Uses Lead Acid Battery Only Terrestrial Use Nickel Cadmium Battery Both Terrestrial And Space Use Nickel Hydrogen Battery Only Space Use Nickel Metal Hydride Only Terrestrial Use Lithium Ion Battery Terrestrial And Space Use  Advances In Spacecraft Batteries ❖ Earlier spacecrafts used NiCd batteries. They had limited capabilities and limited life. ❖ As the storage requirements grew, NiCd gave way to NiH2 batteries. This improved the storage capability from 30 Wh / Kg to 60 Wh / Kg for NiH2 batteries. Life expectancy from 7 to 15 years. ❖ The latest entry into the scene is Li-Ion batteries which offer 120 Wh / Kg storage. Life is expected to be 15 years.  Lithium Ion Cell Parameters Specific Energy : 100 - 140 Wh/kg Energy Density : 200 - 300 Wh/l Charge voltage limit : 4.2 V Typical charge voltage : 4.1 V Av. Discharge : 3.6 V voltage Typ. discharge : 3.0 V voltage Discharge voltage limit : 2.7/2.5 V Temp. of operation : 10°C - 30°C Charge efficiency : 100% https://youtu.be/5JZ8E7B4FAY Wh efficiency : >90% Self discharge : < 10%/month  Comparison Of Different Cell Chemistries During Discharge At C/2 Rate At 20°c Saft, Melco, Lg, Sony Cells - (Normalized) 2  Limitations of Li-ION Batteries ❖ Highly intolerant to overcharge / deep discharge ❖ Over charge/ over discharge, short, high/ low temperatures result in abuse & damage. ❖ Need elaborate charging scheme and cell balancing in a battery ❖ Bypass electronics needed to take care of open mode failure ❖ limited voltage discharge needed to avoid irreversible damage to the cell  Small Satellite Power System ❖ Mass ❖ Volume ❖ Cost ❖ Realization Time  Choice of Power System ❖ Photovoltaic Cells As Power Source ❖ Rechargeable Battery For Energy Storage ❖ Simple Load & Battery Management Electronics Type of Orbit & Power System design ❖ Orbit Duration ~100 minutes ❖ Sunlit Duration ~ 65 minutes Eclipse Duration ~35 minutes ❖ Sun aspect angle and % of eclipse duration in given orbit is a key factor in power system design ❖ Positive Energy Balance to be ensured with battery DOD m*g⇒Climbing SUM(F) < m*g⇒Declining ❖ For Hovering If all motor speeds are the same and can compensate for drone’s weight then, SUM(F)=m*g⇒Hovering  Working Principle of Drone Motions of Drone Roll ⮚ Roll is making the drone fly sideways ,either left or right. ⮚ Roll is controlled with the aileron stick in the corresponding direction.  Working Principle of Drone Motions of Drone Pitch ⮚ Pitch is making the drone tilt forward or backward ⮚ Pitch is controlled with the airelon stick in the corresponding direction  Working Principle of Drone Motions of Drone Yaw ⮚ Yaw is making the drone head move to the left or right. ⮚ It is also the rotation of the drone about the central axis ⮚ Yaw can be controlled through the throttle stick, also called Rudder  Controlling of a Drone ⮚ The stability of the drone is taken care via inputs from sensors. ⮚ The user sends information through a remote transmitting either through bluetooth or radio Controlling of a Drone  Roll Control of Drone Working Principle ⮚ For a quad rotor to roll, it needs a torque about the center of gravity along lengthwise (front - back) direction.)  Pitch Control of Drone Working Principle: ⮚ To perform a Pitch movement it needs to generate torque at the center of gravity along the Lateral axis  Yaw Control of Drone Working Principle: ⮚ Unlike roll and pitch, yaw is the effect of the rotors on the frame of quad rotor. ⮚ When a propeller turns clockwise it generates counterclockwise torque on the frame to equalize the torques. ⮚ Diagonally opposite rotors generate torque in the same direction (Clockwise or Counter/Anticlockwise).  Throttle Control of Drone Working Principle: ⮚ Throttle up/down indicates moving the quad rotor to go higher/ lower. ⮚ Throttle up is achieved by increasing the speed of all rotors at the same time (and vice versa for throttle down). ⮚ This causes propeller to increase the thrust generated that help the drone go higher. Drone Satellite Launch Vehicle – 2023 Design of Drone  Components of a Drone ❖ Frame ❖ Arms ❖ Propulsion and vertical motion ❖ Propulsion ❖ Propeller ❖ BLDC Motors ❖ ESC(Electronic speed controller) ❖ LIPO Battery & battery charger ❖ Flight controllers (Require for Autopilot APM 2.8) ❖ Transmitter & Receiver ❖ GPS ❖ Landing gears  Drone Frame ⮚ The structure that holds all the components together. one of the most important part of quad copter is its frame because it supports motors and other electronics and prevents them from vibrations. ⮚ You have to be very precise while making it. They need to be designed to be strong but also lightweight.  Drone Arms ⮚ Arms basically used for preventing the damage to the motors or expensive electronics on the frame in the event of any crash. ⮚ Arms can be built at home using Aluminum or hard plastic tubing.  Drone Landing Gear ⮚ Usually landing gears use for landing the drone without any damage. ⮚ Landing gears also used for compensating the ground interface on sensors which are located on on-board flight controller.  Drone Propulsion ⮚ Propulsion is the act of moving or propelling the object in forward direction. In an airplane, the engine is part of the propulsion unit along with the blades (propellers). ⮚ In a quad rotor, we can’t attach jet engines, so we use motors and propellers as our propulsion unit to provide propulsion.  Drone Motor Brushless DC motor(BLDC) ⮚ A brushless DC motor (also known as a BLDC motor or BL motor) is an electronically commutated DC motor which does not have brushes. The controller provides pulses of current to the motor windings which control the speed and torque of the synchronous motor. ⮚ A brushless motor, by contrast, utilizes a permanent magnet as its external rotor. In addition, it uses three Note- Motor chosen for the drone should meet the following phases of driving coils and a specialized sensor that specifications: ⮚ Light weight tracks rotor position. ⮚ High speed & torque  Drone Propeller ⮚ It is a device which converts the rotational motion into the thrust. ⮚ A device with several flat metal parts (blades) which turn round very fast in order to make a quadcopter or a plane move. ⮚ Drone propellers used to be smaller in size and usually made up of carbon fiber or plastic material.  Parameters of a Standard Drone Propeller 1. Diameter of a propeller: The end to end distance of the propeller is called the diameter of the propeller. 2. Pitch: Propeller pitch is a linear dimension usually expressed in inches, feet, millimeters, or meters, and is equal to the advance of the propeller in one revolution. ⮚ Dimension 10*4.7 inch ⮚ 4 Propellers ⮚ Directly attached to the motor ⮚ 2 Each rotating CW & CCW ⮚ Propeller use for to drive Drone (Quad copter)  Types of Batteries ⮚ Batteries are of different types, made with different variety of materials. Some of these batteries are not rechargeable, such as alkaline batteries and some are rechargeable such as Li-ion, Ni-Cd, LiPo, Ni-MH, lead acid etc. Wet cell batteries: ⮚ A wet cell battery generates power from an electrode and a liquid electrolyte solution. E.g. Lead Acid batteries, Ni-Cd batteries, etc. Dry cell batteries: ⮚ A dry cell uses a paste electrolyte, with only enough moisture to allow current to flow. E.g. AA, AAA, Li- ion, LiPo etc.  Drone Battery (Lithium Polymer) ⮚ For our purpose of providing current for a drone, LiPo batteries are a perfect fit. ⮚ The battery used in a drone is a Lithium Polymer or LiPo battery. ⮚ This battery has various advantages over other traditional batteries. ⮚ The most important reasons for using LiPo batteries in drones are that they are energy dense and light in weight. ⮚ If you compare various types of batteries of equal weight, LiPo batteries provide a very high energy i.e. very high current. Hence, LiPo batteries have an ability to provide more current at very light weight. This helps your drone to get high energy without much increase in overall weight.  Selection of Lithium Polymer Battery High Energy Density ⮚ LiPo batteries have a very high energy density i.e. they can carry the maximum amount of energy per unit of weight of the battery. ⮚ This keeps the battery light and with sufficient energy to power an entire drone + its own weight. C-Rating ⮚ Another important factor in a LiPo battery is the C Rating of the battery. C-Rating of a battery refers to the maximum safe discharge current that a battery can provide (without exploding). C-Rating is calculated as: (Max safe current in mA) or (mAh capacity of the battery). ⮚ Drone motors, especially multi-rotors, generally require a very high current to lift it up. To ensure this, the batteries require to be of a high C-Rating. Many drones use C-Rating between 15C to 25C.  Selection of Lithium Polymer Battery Voltage ⮚ The operational voltage of a single cell of a LiPo battery is 3.7V. We can get to different values of operational voltages by adding these cells in series and parallel combinations. Discharge Profile ⮚ A fully charged single cell LiPo battery has a voltage of ~4.2 V. However, very quickly after starting to use the battery (at ~90% of the charge), the voltage falls to 3.7 V where it stays stable for most of the battery operation. When the battery charge reaches 20%, the voltage starts dropping sharply below 3.7V.  Drone Battery Charger ⮚ It is the source of power for the drone setup. ⮚ A lithium-polymer (LiPo, LIP or Li-Poly) battery is a type of rechargeable battery that uses a soft polymer casing so that the lithium-ion battery inside it rests in a soft external “pouch.”  Drone Electronic Speed Controller (ESC) An electronic speed control (ESC) is an electronic circuit that controls and regulates the speed of an electric motor. It may also provide reversing of the motor and dynamic braking. Miniature electronic speed controls are used in electrically powered radio controlled models.  Drone Flight Controller The flight controller is the brain of a drone. A small box filled with intelligent electronics and software, which monitors and controls everything the drone does. And just like the brains of different organisms, flight controllers also vary in sizes and complexity. Some of the flight controllers are: ⮚ Autopilot APM ⮚ KK Board ⮚ Pixhawk ⮚ Naza DJI ⮚ Arduino Board Autopilot APM (with Power module)  Drone Flight Controller KK Board Pixhawk  Drone Flight Controller Naza DJI Arduino Mega  Drone Transmitter and Receiver ⮚ 2.4 GHz ⮚ 1000m Range ⮚ Drone requires minimum 6 channel transmitter & receiver  Drone Autopilot (Autonomous) ❖ A drone with GPS and Autopilot system including a camera gives plenty of aerial options including fly according to a pre-programmed route. ❖ GPS is used for tracking and navigating the drone. ❖ UBlox 7M (shown in the diagram) is most suitable GPS for tracing and navigating the drone. Drone Satellite Launch Vehicle - 2023 Thank You